Sapolsky Dismantles Single-Cause Buckets in Human Behavioral Biology

萨波尔斯基破除人类行为生物学中的单一归因论 人类行为无法仅通过遗传学或心理学等孤立学科来解释，因为每种行为都源于一条从未中断的因果连续体，将即刻的神经元放电与演化选择紧密相连。 罗伯特·萨波尔斯基（Robert Sapolsky）教授通过剖析机体内部生理机制与大脑思维及行动之间持续的双向反馈回路，阐明了人类行为生物学的基本原则。他批判了还原论式的范畴化思维，指出将连续现象机械划分为孤立的学科范畴会导致认知扭曲，甚至引发历史上如优生学和额叶切除术等科学暴行。为了应对这种复杂性，本课程采用多学科框架，按时间顺序逆向追溯行为的成因——从即刻的神经放电与感官线索，一路回溯至激素、早期发育、遗传学以及演化选择压力。萨波尔斯基还概述了研究行为时的三大认知难关：认清人类在哪些方面只是普通动物、看清共有的生理机制如何被运用于独特的认知方式，以及识别人类独有的、在动物界绝无先例的行为。 罗伯特·萨波尔斯基指出，人类行为受持续的双向反馈回路驱动，其中躯体状态会改变大脑功能，而认知状态也会改变外周生理机能。 (6:16) 范畴化思维虽然为记忆与检索提供了认知捷径，但会夸大任意界线两侧的差异，同时掩盖类别内部的变化，从而系统性地扭曲现实。 (11:42) 行为生物学揭示了人类与动物之间的三种不同关系：直接的生理等效性、将共有生理机制用于纯粹的认知触发，以及完全独特的人类行为。 (33:06) 科学界单一学科的还原论在历史上曾导致灾难性后果，从华生式行为主义，到额叶切除术，再到康拉德·洛伦兹（Konrad Lorenz）的纳粹优生学宣传皆是如此。 (25:18)

In an introductory lecture for Stanford's Human Behavioral Biology course, Professor Robert Sapolsky argues that human behavior cannot be understood through isolated disciplines, but must instead be analyzed as a continuous, bidirectional feedback loop between physiology and the environment stretching from split-second neural events to evolutionary history. Bidirectional Mind-Body Feedback and Legal Precedents (3:17) Sapolsky establishes that internal physiology directly alters brain function and overt decision-making, citing successful legal defenses where bodily states—such as menstruation, amygdala brain tumors, blood sugar crashes from junk food in the Dan White trial, and massive anabolic steroid abuse—were used to explain homicidal aggression. Conversely, purely mental processes instantly produce peripheral physiological reactions; deliberately contemplating one's own mortality triggers autonomic arousal and elevates heart rate. Sapolsky frames behavioral biology as the continuous investigation of this two-way loop. The Hazards of Categorical Thinking (7:27) To handle cognitive complexity, humans divide continuous phenomena into discrete categories, as seen in color naming, grading thresholds, and telephone number chunking. Sapolsky warns that categorical thinking introduces three major analytical distortions: underestimating differences between items placed within the same bucket (such as confusing a bear with a pear due to phonetic boundaries), overestimating differences between items separated by an arbitrary line (such as a failing exam score of 65 versus a passing score of 66), and failing to grasp the wider context. The Destructive History of Disciplinary Silos (25:18) Sapolsky warns that biological reductionism is not a benign academic error but has repeatedly produced severe intellectual and social damage. He points to behavioral psychologist John Watson’s claim that controlled environmental reinforcement could manufacture any human outcome regardless of biology; Portuguese neurologist António Egas Moniz’s Nobel Prize-winning invention of the prefrontal lobotomy, which rationalized widespread irreversible brain mutilation; and ethologist Konrad Lorenz using biological arguments to justify Nazi racial hygiene and eugenics. Three Tiers of Human Behavioral Comparison (33:06) To evaluate behavior without single-bucket bias, Sapolsky outlines three distinct tiers. First, humans often function as ordinary animals, exemplified by pheromonal ovulatory synchrony occurring in female hamsters and mirrored in college roommates as the Wellesley Effect. Second, humans use shared mammalian physiology in unprecedented ways, such as chess grandmasters elevating their blood pressure for hours and burning thousands of calories purely through abstract cognitive stress rather than physical combat. Third, humans display behaviors without clear animal parallels, including non-reproductive sex sustained across decades paired with language debriefing, or the pairing of sexual behavior with physical violence. Course Methodology and Structural Design (19:56) The course approaches behavior through an expanding chronological sequence: beginning with the firing action potential 0.5 seconds before an act, tracing back to sensory triggers minutes earlier, circulating hormones hours prior, fetal environment, genetics, and ultimately evolutionary pressures spanning millennia. The syllabus spends its first half introducing individual disciplines—including evolutionary theory, genetics, ethology, neuroscience, and endocrinology—before dismantling those buckets in the second half through James Gleick’s chaos theory to examine complex phenomena like aggression, depression, and language. Sapolsky contends that mastering behavioral biology is a vital civic responsibility for evaluating public policy, juries, and personal relationships. However, despite advocating for an open-ended, essay-based evaluation that rejects rigid academic categorizations, the practical reality of managing an enormous lecture enrollment forces the course to rely primarily on multiple-choice midterm and final examinations.

斯坦福大学教授Robert Sapolsky指出，人类行为源于身体生理与心理状态之间持续的双向反馈，必须打破单一学科的分类思维，采用跨越神经、激素乃至演化尺度的整合视角进行解析。 生理与心理的双向反馈 (3:17) Sapolsky通过一系列现实案例表明，身体内部的生物学状态能对大脑决策与行为产生直接影响。在司法实践中，经期激素波动、杏仁核脑肿瘤、高糖垃圾食品引发的血糖震荡（如Dan White刺杀案中的“Twinkie辩护”），以及滥用合成类固醇导致的暴怒，均曾被辩护方成功用于解释谋杀行为并获得减刑或免责。这些案例证明，身体机能的变化能够剧烈改变个体的认知与冲动控制能力。 反过来，纯粹的心理认知也能瞬间引发外周生理机能的剧烈反应。Sapolsky以自主演练为例指出，当一个人在床上静止并思考自己的死亡与心脏停跳时，交感神经系统会立刻被唤醒并导致心率加快。国际象棋特级大师在比赛中仅凭纯粹的脑力推演和棋盘落子，即可维持长达数小时的高血压并每天消耗数千卡路里，其生理应激反应不亚于大草原上撕咬对手的雄性狒狒。这种双向回路确立了人类行为生物学的核心基石。 分类思维的认知陷阱 (7:27) 面对错综复杂的人类行为，人类倾向于依靠分类思维建立认知捷径，但这会带来三种系统性的失真：低估同类事物之间的实质差异、夸大跨越人为界线的事物差异，以及因紧盯局部框架而忽视全局。例如，以语言边界划分色谱会导致人们对处于词汇核心位置的颜色记忆深刻，却混淆边界上的细微色差；芬兰语因不区分清浊辅音，曾让医生对Sapolsky提出“拿熊（bear）还是梨（pear）练习睾丸活检”的语言混淆；大学考试中65分不及格与66分及格的1分差距，也被人为边界赋予了截然不同的意义。 在科研领域，落入单一学科范畴会导致危险的还原论偏见。例如解释“母鸡为何穿过马路”，内分泌学家、解剖学家与演化生物学家往往各自退守在激素、骨骼结构或基因复制的单一框架内。Sapolsky强调，学科分类只是暂时为了方便描述不同阶段结果的观察平台，真实的行为绝不存在孤立的“学科水桶”。 单一学科还原论的灾难历史 (25:18) 历史表明，顶尖科学家陷入单一维度的绝对化思维曾导致灾难性的社会后果。行为主义创始人John Watson在1912年声称，只要完全掌控环境和奖惩条件，他能将任何健康婴儿培养成医生、律师乃至盗贼，完全忽视了胎儿期蛋白质营养不良等生物学底层的决定性制约。神经生物学领域的过度还原同样代价惨重：葡萄牙神经学家António Egas Moniz声称通过调整脑突触可以治愈一切精神疾病，并因发明额叶切除术获得1949年诺贝尔奖，但这一手术随后导致数以万计甚至数十万并未患有严重器质性脑病的人遭受不可逆的大脑毁损。 更为极端的是将生物学概念与意识形态捆绑。著名动物习性学家Konrad Lorenz曾以反对“家养退化”和维护种族纯洁为名，发表支持纳粹优生学的言论，直接为大屠杀提供了所谓的科学理论伪装。Sapolsky指出，这些历史教训证明，用单一学科逻辑替代复杂整体解释，往往不仅在学术上破产，更在现实中酿成严重的人道灾难。 理解人类行为的三大智力挑战 (33:06) Sapolsky将人类行为生物学的学习难点归纳为三项智力挑战。第一，接受人类有时只是“普通动物”。雌性仓鼠通过气味信息素调节能实现排卵周期同步，且优势个体主导从属个体；人类同样存在“韦尔斯利效应（Wellesley Effect）”，女大学生室友在无意识间通过嗅觉信号发生月经周期同步，且外向主导者带动同室伙伴，这与人类同黑猩猩高度重合的基因组现实相符。 第二，人类常将动物共有的基础生理机制运用于前所未有的抽象场景。人类会为了万里之外受难的陌生难民、虚构小说中的人物甚至受伤的宠物产生深刻的共情与神经内分泌应激。第三，人类演化出了自然界绝无仅有的独特行为模式，如长达数十年伴随语言交流的非生殖性日常性行为，以及将暴力与性冲动相互交织的病态倾向。这要求研究者既不能否认人类的动物本能，也不能用低等动物模型生搬硬套人类特有的复杂心理。 从毫秒到百万年的跨学科整合架构 (19:56) 为了在方法论上彻底摆脱分类水桶的束缚，该课程建立了一套沿时间轴逆行追踪行为成因的跨学科分析框架。解析一项具体行为时，首先对其进行客观描述，随后向前倒推半秒，探究大脑回路的具体放电情况；再向前倒推数秒至数分钟，分析诱发神经冲动的环境感官刺激（声音、气味）；紧接着追溯数小时前体内的循环激素水平，进而引向编码这些激素的基因调控、胎儿及早期发育环境对神经可塑性的塑造，最终回溯至数百万年乃至数千万年前塑造该基因库的演化选择压力。 课程前半段将逐一解析演化理论、分子与行为遗传学、动物习性学、神经科学及内分泌学等基础工具；后半段则结合混沌与复杂性理论，打破还原论假设，全面剖析攻击性、性行为、育儿、抑郁症及精神分裂症等复合行为模式。Sapolsky主张，行为生物学并非仅供生物专业研习的学院知识，而是一项关乎陪审团定罪、公共政策制定以及社会福利投入的基础公民素养。 人类行为不能被视为钟表般可以通过拆解零件再重新拼接来理解的机械系统，而更像无法简单还原的云雾与降雨过程。理解复杂行为需要克服分类思维的本能偏狭，但如何在庞杂漫长的时间因果链条与多学科交叉中建立精确的因果判定标准，仍是行为生物学需要持续探索的核心课题。

## Background 该视频由斯坦福大学（Stanford University）于2011年2月1日发布在YouTube平台上。视频记录了罗伯特·萨波尔斯基（Robert Sapolsky）教授在2010年3月29日讲授的《人类行为生物学》（BIO 150）开篇导论，主要阐释了课程的核心前提以及如何抵制和避免单一学科的“分类思维”。 ## TL;DR 萨波尔斯基教授通过行为异常案例与法庭生理抗辩，揭示了生理机制与外显行为之间深刻的双向互动，并系统剖析了人类依赖“分类思维”带来的认知便利与三大盲区。他援引行为主义、额叶切除术和纳粹优生学的历史教训，警示将复杂行为割裂归因于单一学科“水桶”的巨大危害，主张从即时神经回路一路回溯至数百万年演化的全时序视角。讲座还提出了理解人类行为生物学的三重维度——从人类作为普通动物的生理同步（如韦尔斯利效应），到将普通生理机制用于纯认知刺激，再到人类独有的行为模式，并倡导以超越经典还原论的混沌复杂性视角来理解生命。 ## Atmosphere & style 整堂讲座充满冷面幽默与机智自嘲，萨波尔斯基用把“梨”听成“熊”的活检轶事以及曼哈顿地铁站台猜谜等生动桥段，引得阶梯教室笑声与掌声频起。然而在剖析脑白质切除术与纳粹优生理论等学术黑历史时，语调又骤然转为冷峻与警惕，展现出极强的知识分量与道德审视。这种在轻松戏谑与严肃思辨之间的自如切换，赋予了课堂极其抓人的智识张力，让听众在打破既有学科框架的冲击中，真切体会到探索复杂生命本质的震撼与魅力。 ## Bulletin - [07:27](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=447s) 人类大脑倾向于使用分类思维来降低记忆和认知成本，但这会带来三大陷阱：低估同类内部差异、夸大跨边界微小差异，以及过度依赖既定范式而忽视全局。 - [25:18](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1518s) 历史上约翰·华生、埃加斯·莫尼斯及康拉德·洛伦兹等顶尖科学家，因深陷单一学科“水桶”的决定论偏见，曾分别导致了激进环境论、额叶切除术滥用以及纳粹种族清洗等灾难性后果。 - [33:06](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1986s) 理解人类行为生物学面临三重挑战：首先承认人类有时仅是普通动物（如与啮齿类相同的排卵同步现象），其次是人类能用普通生理机制应对独特的认知刺激（如棋手静坐消耗数千卡路里），最后是人类拥有无动物先例的独特行为（如非繁殖性高频性行为与复杂语言）。 - [46:24](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2784s) 萨波尔斯基指出复杂行为不能采用拆解零件的传统还原论来解释，它更像不可分割的云朵而非钟表，因此课程引入了复杂性与混沌学范式。 ## Key takeaways - [03:17](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=197s) 生理状态与外显行为之间存在强烈的双向机制：身体的生理改变会剧烈影响大脑与行为（如经期、脑瘤、垃圾食品在法庭上的脱罪辩护），而大脑中的纯认知念头也能迅速改变外周生理指标（如想象死亡引发心率飙升）。 - [11:42](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=702s) 连续体与分类思维的权衡：现实世界中的光谱和声学频率是完全连续的，人类为了便于记忆和处理而强行划分离散边界，这构成了分类思维的基础。 - [14:44](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=884s) 分类思维存在三大核心陷阱：一是低估同类内部差异（如芬兰语不区分B与P导致把梨听成熊），二是过度夸大边界两侧微小差距（如65分及格与64分不及格），三是只见标签模式而丧失宏观视野（如非标准格式电话号码导致记错）。 - [23:22](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1402s) 学科划分的“水桶”是人为且虚构的：无论是内分泌学、神经生物学还是进化生物学，都只是描述同一种生物学因果链条在不同时间尺度上的便捷切入点。 - [20:22](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1222s) 行为分析需要自近端至远端的系统性时间轴回溯：从行为发生前半秒的神经回路放电、前数秒的感官刺激感知，逐层退回到过去数小时的激素水平、胎儿发育期，直至数百万年前的进化选择。 - [27:50](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1670s) 单一学科决定论在科学史上曾造成巨大灾难：华生的绝对环境决定论、莫尼斯推崇的额叶切除术，以及洛伦兹为纳粹种族优生学背书，都暴露出学术“水桶思维”的致命危险。 - [35:59](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2159s) 人类与动物的生理同源性：以雌性仓鼠及人类大一女生的“韦尔斯利效应”为例，排卵同步现象均由嗅觉系统与信息素介导，并受到个体社会主导地位的影响。 - [36:35](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2195s) 人类擅长用普通动物生理机制处理抽象心理认知：国际象棋大师仅靠静坐脑力思考就能单日消耗数千卡路里并维持马拉松级的血压激增，与狒狒在自然界生死搏杀的生理应激完全一致。 - [39:11](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2351s) 人类拥有动物界绝无仅有的行为领域：例如复杂的象征性语言、日常非繁殖目的性行为与长谈，以及将攻击暴力与性欲高度混淆的心理结构。 - [44:29](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2669s) 行为生物学是每个现代公民的必备知识：在担任陪审团成员判定刑责、公共政策投票，或面对抑郁症等亲友健康问题时，普通人每时每刻都在实践行为生物学的判断。 - [47:35](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2855s) 经典还原论不适用于解释人类行为：行为如同云朵而非机械钟表，无法通过将其拆碎成微小零件研究后再简单拼装来理解整体行为。 - [54:30](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=3270s) 课程考核设计遵循从“打牢事实”到“融会贯通”：前半学期重点掌握各学科分支的专业词汇与基础事实，后半学期及期末考试则要求彻底打破分类边界、跨学科整合具体行为案例。 ## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=0s) 课程开场与一个突变案例 罗伯特·萨波尔斯基（Robert Sapolsky）教授在斯坦福大学开启了《人类行为生物学》（BIO 150）的第一堂课。为了让学生迅速进入思考状态，他抛出了一个虚构的案例场景：一名 40 岁的男子，过着典型的郊区平静生活，结婚 15 年，育有两个孩子，养着“3.5 条狗”，一切平稳顺利。然而毫无征兆地，他在饮水机旁因为别人对某支棒球队的评价感到不顺眼，突然挥拳揍向同事的脸。三个月后，与他恩爱 15 年的妻子发现，他竟在当地 Safeway 超市与一名 16 岁收银员发生婚外情。又过了三个月，他卷走了公司的全部资产潜逃，从此人间蒸发。 面对这个案例，萨波尔斯基列出了三种解释可能性：第一，这人从骨子里就是个大混蛋（creep）；第二，他正在经历一场人类所能想象到的最不成熟的中年危机；第三，他的脑内存在一个单一基因的突变。萨波尔斯基向全班明确指出，在后续课程中大家会发现，某种神经系统疾病的典型临床表征正与此完全吻合，而那背后的罪魁祸首仅仅是一个失常的基因。 ### [01:33](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=93s) 课堂观念调查：从自由意志到天性与教养 萨波尔斯基随后通过举手调查来摸底在座学生的既有观念。调查的问题层层递进，涉及认知偏好与哲学信仰：从性取向是否存在遗传影响、产前事件是否可能影响 30 年后的政治观点，再到是否能借助生物学来解释宗教信仰。在涉及形而上学的追问中，他调查了相信上帝、灵魂、邪恶与自由意志的人数。当看到大量学生为自由意志举手时，他微笑着调侃道：“这一情况将会改变。”随后全场爆发出笑声。 在确认全场是否有人“真正相信演化论”后，他转向攻击性与智力上的性别生物学差异，并向学生抛出经典的天性与教养（nature vs. nurture）之争。当全班几乎一致认同“天性与教养之间存在美妙、迷人且细致的互动”时，萨波尔斯基打趣称大家都已经把课程吃透了，可以直接拿 A+ 毕业。 ```mermaid flowchart TD accTitle: Class Survey on Biological Influence and Beliefs accDescr: A branching chart showing the sequence of philosophical and biological questions Sapolsky posed to survey students' assumptions. A["课堂观念摸底调查"] --> B["生物学与认知"] A --> C["哲学与形而上学"] A --> D["天性与教养争论"] B --> B1["性取向遗传影响"] B --> B2["产前环境对政治倾向的影响"] B --> B3["性别的攻击性与智力差异"] C --> C1["上帝与灵魂信仰"] C --> C2["邪恶与演化论"] C --> C3["自由意志（'这将会改变'）"] D --> D1["纯天性论"] D --> D2["纯教养论"] D --> D3["复杂细致的交互作用"] ``` ### [03:17](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=197s) 凶杀辩护与生理-行为的双向机制 萨波尔斯基接着列出了看似毫不相关的四种情况，让学生猜测它们的共同点：经期来潮、脑部肿瘤、大量食用垃圾食品、注射促合成代谢类固醇（anabolic steroids）。在学生猜出“激素”这一中间环节后，他揭晓了终极答案：这四种生理状态都在法庭上被成功采纳过，用来为谋杀犯脱罪或争取轻判。 他逐一拆解了这四起法律先例： - **经期**：有判例表明，因当事女性在行凶时正处于经期，陪审团据此对其予以脱罪；文献也表明女性攻击行为有相当一部分发生在经期前后。 - **脑瘤**：长在杏仁核（amygdala）上的肿瘤会导致不可控的暴力行为，这已在法庭辩护中得到有效采纳。 - **垃圾食品**：旧金山历史上刺杀市长与哈维·米尔克（Harvey Milk）的丹·怀特（Dan White），其律师提出了著名的“Twinkie 辩护”（Twinkie defense），称对垃圾食品的成瘾导致其血糖剧烈波动，最终促成了罪行，并成功换取了极短的刑期。 - **类固醇**：健美运动员因大剂量滥用睾酮衍生类固醇导致失控暴力的案例比比皆是。 借由这四件事，萨波尔斯基提炼出了整门课程的第一个核心论点：“有时候，你身体里发生的生理变化，会剧烈影响你的大脑活动。” 紧接着，他展示了相反方向的影响机制：如果今晚睡前身心放松、心跳缓慢时，你开始专注想象自己的心脏不可能永远跳动、嘴唇开始发青、血液循环放缓、脚趾逐渐冰凉，你的心率就会随之飙升。这引出了第二个核心论点：“有时候，你脑子里的想法会波及身体的每一个哨所。”萨波尔斯基强调，本门课探讨的正是生理机制与外显行为、底层情绪、认知与记忆之间的双向深层交织。 ### [07:27](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=447s) 分类思维的优势与认知局限 面对人类极端复杂且异常的社会行为，大脑为了简化并处理连续流动的庞杂信息，往往会采取一种本能策略——分类思维（categorical thinking）。人类倾向于将原本连续的事物强行切割成带有离散边界的类别并打上标签。 为了证明这一认知习惯的存在，萨波尔斯基现场画了一条线，学生们立刻以“一英尺”（12 英寸）为标准（联想到 8.5×11 英寸的标准纸张）进行估算；在谈及优秀跑者时，人们脑海中存在一条“4 分钟跑完 1 英里”的离散优劣分界线；但在评价画家时，若说“这位画家能用 11 种颜色作画”就毫无意义，因为人类大脑并没有针对颜料数量建立质量评价分类。 随后，萨波尔斯基以彩虹的连续光谱（从紫到红）为例解释分类思维的本质机理。物理上的光波波长是无限连续的，但语言规则却人为地划定界限：“从这里到这里是红色的，这里是橙色的。”人类之所以采用分类思维，核心原因在于“它让信息的存储变得更加容易”，人们只需记住“这是一个亚 4 分钟跑者”、“一条尺子长短的线”或“橙色”，而无需记忆绝对精确的物理数值。萨波尔斯基指出，跨语言研究证明了这一点：不同语言族群在划分光谱边界时的位置完全不同，导致其母语者对色彩特征的记忆认知画像也呈现出截然不同的差异。 - 萨波尔斯基对本门课的核心任务做出警示：“我们并不想去弄明白鸟类迁徙为何不会迷路；我们要理解的是人类的行为。比这更糟糕、更困难的是人类的社会行为，而在某些情况下，最困难的是理解那些严重异常的人类行为。” ### [11:42](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=702s) 连续体与认知便利：分类思维的起源与代价 人类的大脑在面对复杂而连续的外部世界时，天然倾向于将其强行切分成离散的类别。如果给人们展示一种处于该颜色定义范围正中心的标准色，随后测试他们是否见过这种颜色，人们的记忆准确率要远远高于展示处于两种颜色过渡边界上的颜色；而且这种记忆差异直接取决于受测者所使用的语言如何划分色谱。面对无限连续的光波长，大脑必须将其打碎成片段，因为唯有这样处理事实才更轻松。 在图形认知中也是同样的道理。如果画出四个几何图形，其中前三个有明确的语言类别可以定义，而第四个只是一团无法名状的卷曲乱线，一小时后再询问受试者是否见过这些图形，人们辨认有名字图形的准确率会压倒性地高于那团乱线。对此，Robert Sapolsky 总结道：“Thinking in categories makes it easier for us to remember stuff.” 这是一种针对复杂现实的经典认知妥协，但这种思维方式也伴随着巨大的认知缺陷。 ```mermaid flowchart TD accTitle: 现实连续体与分类思维的认知转化 accDescr: 展示客观连续的世界如何被人类语言与认知强行切分为类别，从而带来利弊。 subgraph Reality["客观现实（连续体）"] R1["无限连续的波长（颜色）"] R2["连续变化的声学频谱"] R3["复杂的非规则几何形态"] end subgraph Cognition["认知加工（分类处理）"] C1["强行划定范畴边界"] C2["打上语言标签与名称"] end subgraph Consequences["结果与代价"] Adv["认知优势：便于记忆与评估"] Dis["认知缺陷：陷入范畴陷阱，割裂全局"] end Reality --> C1 C1 --> C2 C2 --> Adv C2 --> Dis ``` --- ### [12:44](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=764s) “在熊身上练习”：跨越范畴边界与无法分辨同类事物 连续体不仅存在于光波中，也同样存在于人类发音的声学频谱中，不同语言会在不同的频段划定界限。例如英语中有两种微妙的 “th” 发音，母语者往往难以清晰辨别，但对于其他语音界限却极其敏感。而在芬兰语中，人们在生理听觉和认知上并不严格区分爆破音 “B” 和 “P” 的差别。为了说明这种语音分类造成的荒谬误解，Robert Sapolsky 分享了自己早年一段令人捧腹的真实经历：数年前因为某种连他自己都觉得匪夷所思的研究需求，他必须给狒狒做睾丸活检（testicular biopsies）。 由于初中显然没有教过这项技能，他便打电话向医学院泌尿科一位芬兰籍医生请教。对方非常热情地为他讲解了手术细节、需要购买的器材以及成打批发的优惠包装。讲解完毕后，那位芬兰医生认真地对他说，现在你需要做的是积累实操经验，“I want you to practice on a bear.”（我想让你先找只熊练练手）。Sapolsky 彻底惊呆了，反复追问“你开玩笑吧？”对方依然无比笃定地解释，所有住院医都是这么训练的，这是绝佳的练习手段，并补充道：“Either practice on a bear or an apple.” 听到“苹果”那一瞬间，Sapolsky 才恍然大悟——对方说的根本不是狗熊（bear），而是梨子（pear）。针对这种由于缺乏边界区分而闹出的笑话，Sapolsky 指出：“So we see one of the dangers there, which is when you are paying too much attention to categories, you can't differentiate two facts that fall within the same category.” - 人类发音器官能产生的物理声音是完全连续的光谱，语言人为切分了音素的边界。 - 芬兰语使用者不区分 /b/ 与 /p/ 的发音差异，导致“pear”（梨）被发音为类似“bear”（熊）。 - **分类思维的第一大陷阱**：当你过度关注范畴标签时，你将无法辨别落在同一个类别内部的两个客观事实之间的差异。 --- ### [15:01](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=901s) 考试及格线与电话号码：边界夸大与只见树木不见森林 与“低估同类内部差异”相对的，是分类思维带来的第二个弊端：过度夸大边界两侧微小差异的严重程度。每个人在学生时代经历考试焦虑时都能切身体会到这一点——考 65 分与考 66 分在实际掌握的知识水平上几乎没有任何实质性差异，但因为 65 分与 66 分之间恰好被学校划定了一条“及格”与“不及格”的制度红线，原本微不足道的 1 分差距就被无限放大成了天壤之别。一旦在连续体上人为筑起一道界限，人们就再也无法看清边界两端的事物本质上有多么相近。 为了展示分类思维的第三个弊端，Sapolsky 让在场所有学生翻过手中的调查问卷背面，准备记录他即将念出的一串电话号码。他以极快的语速念出一连串数字：`243-2649`、`650-3260`、`256-5779`、`832-2449`、`291-3171`、`231-4026`、`593-2449`、`743-8840`、`831-5287`。虽然这并不计入课程成绩，但 Sapolsky 打趣说，今晚当自己处于拖延症爆发的强迫状态下去批改这些答案时，一定会发现一个现象：一旦数字的排列破坏了“前三位、后四位”的经典电话号码分组范式，记录的准确率就会瞬间崩塌。人们的大脑会在那一瞬间卡壳并陷入恐慌：“等等，这不是电话号码吗？怎么只有一位？接着又是两位？”就在这一瞬间的迷茫中，下一组数字已经溜走了。Sapolsky 指出：“And what we see there is the third example, which is when you pay too much attention to boundaries, you don't see the big picture.” 人们只看到了预设的模式与类别，却丧失了感知整体信息流的能力。 --- ### [17:11](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1031s) 地铁站台猜谜：分类思维如何局限我们的认知模式 为了进一步向学生演示思维定势如何被特定知识背景下的“分类”所绑架，Sapolsky 在黑板上写下了一组数字序列：`4th, 14th, 23rd, 34th`，并现场询问学生下一个数字应该是什么、为什么。台下的学生们开始了五花八门的数学推演，有人猜测是 42，有人计算出振荡幅度后猜测是 45，甚至还有人猜是“70 亿”（7 billionth）。大家全都在数学逻辑、数列递增规律或者奇偶数交叉的常规类别中绞尽脑汁。 随后，一位学生喊出了 “42nd”，当被问及原因时，该学生回答是因为“地铁线路”。Sapolsky 兴奋地宣布答对了，并当场承诺奖励这位学生一个抹了奶油奶酪的百吉饼（bagel with cream cheese）。全场爆发出一阵掌声与欢笑。这串数字根本不是什么数学公式，而是纽约曼哈顿百老汇第七大道线（IRT Broadway – Seventh Avenue Line）等地铁线路的典型停靠站：4街、14街、23街、34街，下一站自然就是时代广场的 42 街。只有纽约客的大脑中预装了这套特定的分类体系。Sapolsky 借此总结了分类思维的三大核心缺陷： ```mermaid flowchart LR accTitle: 分类思维的三大陷阱 accDescr: 总结由于强行设定范畴边界而导致的三种认知偏差 subgraph Pitfalls["分类思维的三大陷阱"] P1["陷阱一：低估同类内部差异<br/>同一范畴内的两个事实被视作毫无区别（如 Bear 与 Pear）"] P2["陷阱二：夸大跨边界微小差异<br/>仅一墙之隔的相似事物被视作天壤之别（如 65 分与 66 分）"] P3["陷阱三：只见标签不见全局<br/>过度死守既定分组范式而丧失宏观视野（如固守电话号码格式）"] end ``` --- ### [20:22](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1222s) 鸡为什么过马路：跨学科“桶思维”与行为生物学的层层推进 这门课程的核心目标，就是研究“人类行为生物学”这一高度复杂的议题，同时竭力避免陷入分类思维的窠臼。Sapolsky 用一个经典的生物学场景做比喻：一只母鸡站在路边，马路对面有一只公鸡做出了某种具有性挑逗和性诱惑的求偶举动；母鸡见状，立刻迈开步子穿过马路跑向公鸡。面对这个古老的问题——“鸡为什么过马路？”不同学科的人会本能地钻进自己所属的学科分类“桶”（bucket）中去寻找自圆其说的单一答案： | 学科阵营（所属的“桶”） | 针对“鸡为什么过马路”的解释范式 | 潜在的片面性陷阱 | |:--- |:--- |:--- | | **内分泌学家** (Endocrinologist) | 母鸡血液中的雌激素水平达到了特定阈值，使得下丘脑的关键脑区对该刺激产生了响应。 | 将复杂行为完全简化为单一激素浓度的驱动。 | | **解剖学家** (Anatomist) | 母鸡骨盆的支点结构及其特定的运动解剖构造，赋予了其奔跑穿过马路的能力。 | 仅从生物力学和机械执行层面解释行为。 | | **进化生物学家** (Evolutionary Biologist) | 在数百万年的漫长岁月中，对雄性求偶信号不产生反应的雌鸡留下的后代基因更少。 | 纯粹诉诸于终极基因选择，忽略即时生理机制。 | 沉溺于单一的学科分类桶中，会让学者患上严重的认知狭隘症：过度拔高自己身处的那个学科桶的地位，误以为某个基因、某种神经递质或某次童年创伤就是解释某种复杂行为的“终极钥匙”。本门课程的根本立意在于跳出所有这些人为设定的范畴限制，正如 Sapolsky 所强调的：“And at every one of those points, resisting the pull to think categorically.” 在后续探讨具体人类行为时，课程将摒弃非黑即白的标签，采取一种自近端向远端层层逆向推导的时序全景框架： - **客观描述行为本身**：首先明确该行为在外观上到底是什么模样，这往往需要比人们预想中更多的客观性。 - **行为发生前半秒（神经回路）**：追溯动作发出前半秒大脑内部发生了什么？哪些神经元在发放？哪些神经环路被激活？ - **行为发生前数秒至数分钟（环境感知）**：在学生刚刚打算安逸地停留在“神经生物学”这个桶里时，立即退后一步追问：究竟是外界环境中的何种气味、声音或感官刺激诱发了这批神经元的放电，进而催生了该行为？从神经再推及感知，拉开系统性多层因果分析的序幕。 ### [23:22](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1402s) 行为背后的时间轴与虚构的“分类水桶” 萨波尔斯基教授将探讨生物学影响的视角进一步向过去推演。如果某种特定的声音或气味激活了神经元并引发行为，那么就要追问：该个体血液中过去几小时的激素水平，是如何改变它对这些刺激的敏感度的？然而，激素并不是孤立存在的。一旦指出某种行为由“激素 X”引起，而激素 X 是由基因编码的，学科讨论便立刻从内分泌学跃迁到了遗传学；既然存在特定基因，它必然受到自然选择的塑造，讨论便随之跨入进化生物学的范畴。同理，讨论引发行为的即时感官刺激，其根源必然牵涉到胚胎发育时期感官系统敏感度的建立。 ```mermaid flowchart TD accTitle: 行为生物学时间追溯链 accDescr: 展示从即时行为一路向过去追溯至远古进化的因果链条 subgraph Recent ["近端触发"] A["即时感官刺激<br/>声音 / 气味"] --> B["神经元激活与行为输出"] C["血液激素水平<br/>过去数小时"] --> A end subgraph Developmental ["发育与遗传"] D["胎儿期与早期发育"] --> C E["个体与种群基因组成"] --> D end subgraph Evolutionary ["终极根源"] F["数千年进化压力与自然选择"] --> E end ``` 所谓的内分泌学、神经生物学、遗传学或进化生物学，并非各自独立的领域，它们不过是在用不同方式表达同一种生物学影响。在萨波尔斯基看来，学科划分的“水桶”从根本上讲是虚构的。任何一个被详细剖析的学科领域，都只是描述先前所有影响最便捷的切入点。正如罗伯特·萨波尔斯基所强调的那样：“在这一层面上，根本就不存在所谓的水桶。它们不过是临时的平台，而每个平台仅仅是用来描述在此之前发生的一切——从数千年以前的进化开始——所产生结果的最轻松、最便捷的方式。”（“And in that regard, there's no buckets. All they are, are temporary platforms. And each platform is simply the easiest, most convenient way of describing the outcome of everything that came beforehand starting with millennia back in evolution.”） ### [25:18](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1518s) 行为主义的傲慢：约翰·华生的环境决定论 打破分类思维听起来像是一套显而易见、人人皆知的漂亮话，许多人可能会质疑：专业生物学家难道不知道这些机制是相互交织的吗？难道这不只是立了一个无人会犯的稻草人靶子吗？萨波尔斯基指出，历史证明许多顶级学者正是由于极端的学科封闭而陷入了灾难性的偏执。他引述了行为主义心理学奠基人之一约翰·华生（John Watson）在 1912 年的名言，展示了环境决定论者的绝对妄自尊大。 华生曾宣称，无论婴儿的出身背景如何，只要允许他完全控制抚养环境，他就能将孩子培养成医生、律师，甚至是乞丐或盗贼。这种思想在 20 世纪 50 年代 B.F. 斯金纳（B. F. Skinner）的研究中达到了顶峰，认为行为可以完全通过奖惩机制与正负强化来塑造。萨波尔斯基反驳道，只要在模型中引入一个最粗糙的变量——例如胎儿时期的严重蛋白质营养不良——华生的断言就会彻底瓦解。华生完全被困在“奖惩机制解释一切”的思维水桶里。萨波尔斯基还顺带提及了一段轶事：华生因一场丑闻被迫离开学术界后，转行成为极其成功的广告高管。正如萨波尔斯基调侃的那样：“这向你证明了一件事——他或许没能如愿将人们塑造成任何他想要的模样，但他显然有本事让人掏钱购买各种各样的无聊小玩意。” - 约翰·华生（1912年）代表性观点：“给我一个健康且没有残疾的婴儿，以及由我自己指定的抚养环境，我保证能把其中任意一个随机挑选的婴儿，训练成我所选定的任何类型的专家——医生、律师、艺术家、商界巨擘，甚至是乞丐和盗贼。”（“Give me a child at birth from any background, and let me control the total environment in which he is raised, and I will turn him into anything I wish him to be-- whether doctor, lawyer, or beggar, or thief.”） - 行为主义的理论缺陷：完全忽视遗传特质、胎儿期营养状况及生理发育对大脑功能的决定性限制。 ### [27:50](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1670s) 额叶切除术的狂妄：埃加斯·莫尼斯的“突触调整” 萨波尔斯基给出的第二段引言来自葡萄牙神经学家埃加斯·莫尼斯（Egas Moniz）。引言声称，正常的心理生活依赖于脑突触的良好运作，心理障碍源于突触失调，因此通过微调突触就能引导思想走入不同通道，并在治疗中取得“只有治愈与好转，绝无失败”的战果。当萨波尔斯基让台下学生猜测这种所谓的“突触微调”究竟是指什么时，有学生回答电休克疗法。 萨波尔斯基纠正道，现实远比电休克更加血腥暴力——莫尼斯所指的正是额叶切除术（Frontal Lobotomy）。所谓调整突触，手段竟是直接切除或毁损患者大脑前部约三分之一的脑组织。莫尼斯甚至凭借发明该手术获得了诺贝尔生理学或医学奖。这段宣言正是他接受诺贝尔奖时的发言。萨波尔斯基严肃地指出，这是精神病学与意识形态合谋的最黑暗篇章之一，导致成千上万原本脑部没有任何器质性病变的患者惨遭不可逆的脑损毁。莫尼斯完全活在“只要理解突触并调整突触就能解决一切问题”的单一学科牢笼中。 - 埃加斯·莫尼斯诺贝尔奖获奖演说核心主张：“正常的精神生活依赖于脑突触的良好运作，而精神障碍的出现则是突触紊乱的结果。因此，突触调整将改变相应的思维并迫使它们进入不同的渠道。使用这种方法，我们获得了治愈和改善，但没有失败。”（“Normal psychic life depends on the good functioning of brain synapses, and mental disorders appear as a result of the synaptic derangements. Synaptic adjustments will then modify the corresponding ideas and force them into different channels. Using this approach, we obtained cures and improvements but no failures.”） - 历史后果：该理论导致数十万患者在缺乏充分科学证据的情况下被实施了不可逆的破坏性脑外科手术。 ### [29:48](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1788s) 种族清洗与印刻理论：康拉德·洛伦兹的致命盲区 第三段引言则展现了分类思维最为致命的一面。引言主张：人类若不被“驯化导致的退化”所毁灭，就必须依靠社会组织进行选择；国家建立在种族理念之上，必须依靠优秀族群的健康本能来“消灭人口中充满残渣的成分”。当学生猜测发言者是否是希特勒时，萨波尔斯基指出希特勒当时忙于政务，发言者实际上是纳粹的核心科学宣传者之一、动物行为学（Ethology）的奠基人康拉德·洛伦兹（Konrad Lorenz）。 洛伦兹因发现鸟类的“印刻现象”（Imprinting）而闻名于世，大众文化常将其描绘为蓄着慈祥白胡须、身穿奥地利背带短裤、身后跟着一群把他当成母亲的小鸭子的和蔼老人。然而，他同时也是狂热的纳粹御用学者，终其一生都未曾对自己在种族清洗理论中的所作所为表示悔过。萨波尔斯基强调，华生、莫尼斯、洛伦兹绝非不入流的三流学者，他们是上个世纪最具影响力的科学家，其思想深刻改变了教育制度、导致成千上万无辜者的大脑被物理摧毁，甚至直接为消灭数百万人生命的浩劫提供了伪科学支撑。这些灾难的根源，正是在于顶尖科学家病态地龟缩在各自狭隘的“水桶”里解释整个世界。因此，本课程的核心目标，就是直面复杂、甚至令人惊骇的人类行为，抵制寻找单一解释的诱惑。 ### [33:06](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1986s) 人类行为生物学的第一大智力挑战：我们其实只是普通动物 在进入具体人类行为的研究之前，萨波尔斯基列举了学习人类行为生物学将面临的三大智力挑战。第一项挑战是：承认并接受在某些情况下人类并不具有任何特殊性，我们同自然界中的其他动物完全一样。 为了生动说明这一点，萨波尔斯基举了雌性仓鼠排卵周期的经典生物学案例。一只雌性仓鼠单独生活在笼子里时，通常维持约每五天一次的规律排卵周期。然而，一旦将另一只雌性仓鼠放入同一个笼子共同生活，在接下来大约一个月的时间里，两只仓鼠的生理周期都会开始延长，并最终逐步走向同步化。萨波尔斯基以此为引子，准备揭示这类看似纯粹属于低等啮齿类的化学通信与生理同步机制，同样在人类身上精密地上演着。 ### [33:59](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2039s) 仓鼠、家畜与韦尔斯利效应：排卵同步现象 在仓鼠等动物中，雌性个体的月经与排卵同步化机制已经被完全破解。这种现象是通过嗅觉与信息素（气味化学信号）在雌性之间传递而实现的；科研人员可以通过对嗅觉系统的电生理记录来证明这一点，或者采用极其低成本的手段——用回形针夹住雌仓鼠的鼻子，同步化现象便会立刻消失。如果向两只雌仓鼠中引入一只雄仓鼠，其释放的雄性信息素会迅速打破这种平衡，导致周期打乱、缩短并去同步化。更为精妙的是，同步化的方向并非随机，永远是由优势地位（Dominant）的雌性来同步从属地位（Subordinate）的雌性。这种由信息素介导的同步机制在山羊、绵羊、狗、猫以及猪身上普遍存在，甚至在爱荷华州的 7-Eleven 便利店里，人们都能像买喷射奶酪（Cheese Whiz）一样买到一罐母猪排卵同步喷雾。 而在人类身上，这一现象同样精准存在，被称为“韦尔斯利效应”（Wellesley Effect）。这项 1970 年在韦尔斯利学院（Wellesley College）针对大一新生宿舍开展的经典研究显示，在合住一年的过程中，同寝室女生的月经周期会逐渐延长并走向同步。这完全是由嗅觉线索介导的：嗅觉存在缺陷的女性无法与室友同步；若女性与男性保持着亲密伴侣关系，这种同步性也会被打破；最为残酷的是，谁同步谁绝非偶然，多项研究显示，性格更加外向、活跃且具主导性的个体往往会主导并同步室友的生理周期。罗伯特·萨波尔斯基教授打趣说，当年读大学时如果和一群生物学家坐在一起吃饭，常会听到诸如“夏天合住时，我赶在 8 月 1 号前就把她的周期给同步了”这类对话。 ```mermaid flowchart TD accTitle: 排卵同步化机制流程图 accDescr: 展示雌性之间通过嗅觉信息素实现排卵同步的过程及雄性信息素或嗅觉缺失造成的干扰 subgraph Signals["信号输入"] Pheromone["主导雌性释放信息素"] MalePhero["雄性信息素介入"] Anosmia["嗅觉缺失 / 物理阻隔"] end subgraph Processing["嗅觉感知与个体地位"] Olfactory["从属雌性嗅觉系统接收"] SocialStatus["优势地位个体主导同步方向"] end subgraph Outcome["生理响应"] Sync["周期延长并实现同步化<br/>（仓鼠 / 猪 / 韦尔斯利效应）"] Desync["去同步化 / 周期缩短破裂"] end Pheromone --> SocialStatus --> Olfactory --> Sync MalePhero --> Desync Anosmia --> Desync ``` --- ### [36:35](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2195s) 人类与动物比较的三重境界：从普通生物到独一无二 理解人类行为生物学的第一重挑战，在于承认人类并不特殊——萨波尔斯基教授指出，比较人类与黑猩猩的基因组会发现两者几乎完全一致，“有时，我们不过是一种极其普通、现成量产的动物（plain old off-the-rack animal）”。然而第二重挑战更为微妙：人类拥有与其他动物完全相同的普通生理机制，却能以完全不可思议的方式运用它。 以国际象棋特级大师巡回赛为例，两位棋手在棋盘前相对而坐，全程静默无声、毫无眼神交流，身体唯一的物理动作仅仅是偶尔抬起手移动一小枚木质棋子。然而在这长达六小时的对局中，他们体内维持的极高血压与长跑马拉松选手完全无异，单凭纯粹的思考就能一天消耗数千卡路里。在干掉对手的王后时，棋手体内的生理激增反应与一头在塞伦盖蒂草原上撕开宿敌腹部的雄性狒狒一模一样。人类可以用完全普通的生理机制去应对独有的认知刺激：我们会因意识到死亡的不可避免而产生压力，会因读到地球另一端某个受苦儿童的新闻而焦虑，会因一辆跑车飞驰而过、连车主脸都没看清就自惭形秽陷入经济挫败感，甚至会因小说虚构角色的不幸遭遇而心痛不已；反过来，人类同样能对素未谋面的远方难民或受伤的宠物产生跨越物种的同理心与情感纽带。 第三重挑战，则是某些人类行为在整个动物界没有任何先例可循。萨波尔斯基举了一个充满戏剧性的反差例子：一对情侣下班回家，聊天、吃晚饭、再聊天，然后上床发生性关系，接着继续聊天入睡；第二天他们重复完全一模一样的流程，日复一日持续整整三十天。“河马要是看到这场景都会觉得恶心反胃，”因为在整个动物界中，几乎没有任何物种会日复一日地进行非繁殖目的的性行为，更不用提在事后彻夜长谈。语言的复杂运用、特殊的性行为模式、乃至将性与暴力攻击性严重混淆的破坏性心理，都是完全属于人类的独有领域。 - “有时，我们不过是一种极其普通、现成量产的动物。”（Robert Sapolsky） - “象棋大师们单凭思考这一项，每天就消耗掉数千卡路里。”（Robert Sapolsky） --- ### [40:26](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2426s) 课程路线图与零门槛机制：拆解思维盒子的跨学科挑战 正是为了应对这些复杂性，本课程的核心策略就是反复抵制分类思维（Categorical Thinking）。萨波尔斯基强调，拒绝分类不仅仅是为了追求精妙与细微的学术美感，更是因为一旦堕入分类思维，“你可能会在一个关乎重大的科学领域里造成无法挽回的恶果。”整个课程的架构被清晰划分为前后两大部分： 前半学期是对各个传统学科“分类盒子”（Buckets）的基础巡礼与工具掌握，涵盖演化理论、分子遗传学、行为遗传学、动物行为学（Ethology）、神经科学以及内分泌学等。萨波尔斯基坦言，前半学期在学习体验上将是一场“彻头彻尾的折磨”（a total pain in the rear），因为通常每隔两堂半讲座，正当学生刚勉强掌握一套专业术语时，教学内容就会突然跳跃到一个全新的学科分类中，令人应接不暇。然而到了后半学期，拆解分类的回报便会集中显现：课程将逐一攻克具体的行为大类——攻击行为、性行为、亲代抚育行为、精神分裂症、抑郁症、人格障碍以及语言使用。届时，每个行为都将从“行为发生前一秒的大脑神经电活动”一路层层追溯到“感官刺激输入”、“激素调节”直至“一千万年前的演化选择压力”，彻底打破各个学科之间的藩篱。 为了让这门关乎人类自身的知识触达所有人，课程被刻意设计为“零先修要求”（No prerequisites）。萨波尔斯基在课堂上笑称：“我由衷地认为，地球上的每个人都应该被拿枪指着头强迫学习这门课。”现场举手表决显示，除了生物学、人类生物学、心理学和人类学背景的学生外，甚至还有英国文学专业的研究生跨界选课。为了帮助完全没有自然科学背景的学生跟上进度，课程除常规的每周讨论班（Sections）外，在前半学期还会针对每次跳跃的学科主题增设专门的“基础补习课”（Catch-up Section）。第一场补习课定于周四晚 7:30 在隔壁教室举行，由经验丰富的助教团队带教演化理论基础，为后续的演化模块讲座做好充足准备。 - “掉进分类思维的陷阱，你可能会在一个关乎重大的科学领域里造成无法挽回的恶果。”（Robert Sapolsky） - “我由衷地认为，地球上的每个人都应该被拿枪指着头强迫学习这门课。”（Robert Sapolsky） ### [44:29](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2669s) 选课建议与行为生物学的现实意义 Robert Sapolsky 建议学生仔细阅读课程讲义中的专业术语。如果在某些学科领域对这些词汇感到非常陌生，就应当积极参加基础补习小课（catch-up sections）。对于那些没有任何科学背景、抱着冒险心态选修本门课的同学，他建议选择及格/不及格（pass/fail）的计分方式，这样可以有效减轻成绩压力，把精力真正放在理解课堂内容上。Sapolsky 强调，即便缺乏理科基础，每个人也完全有必要、并且能够学好这门课程，因为行为生物学与日常生活的社会决策息息相关。 正如 Robert Sapolsky 所说：“Because the obvious argument I would make is everybody has to learn behavioral biology because we're being behavioral biologists every time we serve on a jury.” 无论是担任陪审团成员去衡量罪责，还是参与投票决定是否拨付公共资金解决社会问题，抑或是面对深陷抑郁症的家庭成员——去思考他们究竟是遭受了生物化学层面的病理紊乱还是单纯在放纵自我——每个人在现实中时刻都在扮演行为生物学家的角色，因此成为具备科学常识的公民至关重要。 - **讨论班与考核方式**：本学期每周开设约 18 个讨论小班（sections），不采用硬性分配机制，学生可根据个人时间自由选择适合的时段参加。 - **考试设置**：课程仅安排期中考试和期末考试，不要求撰写学期论文（paper）。期中考试将在学期中段完成所有学科分类讲解（buckets）后进行。 - **课堂微歇（break）**：为了让学生在长时间的高强度听讲中清醒头脑，每次较长的课时中间会安排一次 5 分钟的中场休息。Sapolsky 开玩笑称这刚好够大家站起来排到卫生间队伍的最前端，然后课程就会在大家进门前准时重新开讲。 --- ### [46:24](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2784s) 课程指定书目与“还原论”的局限 Sapolsky 为课程指定了两本必读书籍。第一本是他自己的著作，他幽默地调侃学生甚至不需要阅读它，“只要去多买几本把收据拿给我看，你就能在这门课拿到好成绩”。该书的内容主要与学期后半段紧密挂钩，届时教学团队会提供推荐阅读的核心章节清单。 第二本书则是 James Gleick 所著的《混沌》（*Chaos*）。Sapolsky 指出，这本书历年来在学生群体中都会引发极其极端的两极评价：大约四分之一的人认为它是整门课中最恼人、最无关紧要的阅读材料，对此深恶痛绝；约有一半的人始终没搞明白它到底在讲什么；而剩下的四分之一学生，人生观则会被彻底重塑，“他们不再需要冥想，不再需要别的，他们内心归于平静”。 ```mermaid flowchart TD accTitle: 复杂系统的认知范式对比 accDescr: 对比经典还原论将复杂系统拆解为零件的钟表模型，与混沌学中理解行为与天气的整体云朵模型。 subgraph 传统还原论范式 ["传统还原论范式 (500年历史)"] A["复杂系统"] --> B["拆解为微小零件"] B --> C["逐一理解零件"] C --> D["重新组装 = 理解整体 (钟表模型)"] end subgraph 混沌与复杂性范式 ["混沌与复杂性科学范式 (行为生物学)"] E["生命行为"] --> F["非线性互动系统"] F --> G["无法靠拆解碎片来理解整体 (云朵与降水模型)"] end ``` 这种思想颠覆源于对还原论（reductionism）的打破。过去 500 年来，人类理解复杂系统的主流模型是将其拆分成微小零件，弄懂零件后再拼装复原。然而混沌学表明，这种方法适合修钟表，却根本无法解释复杂的行为。Sapolsky 鲜明地指出：“Behavior is not like a clock. Behavior is like a cloud. And you don't understand rainfall by breaking a cloud down into its component pieces and gluing them back together.” - **学术影响与个人感悟**：Sapolsky 坦言这是自童年绘本《小白鲸》（*Baby Beluga*）以来，第一本让他读到最后一页后立刻翻回封面从头重读的著作，也是大学毕业以来对自己科学思维模式影响最深的书籍。 - **后续课程安排**：课程后半段将有数堂专题讲座探讨混沌与复杂性（complexity），这将迫使学生彻底转变思考行为生物学的既有框架。 - **论文阅读资料**：为避免让学生破费购买厚重且昂贵的论文合辑（reader），Sapolsky 正在全力将所有指定读物转换为可在 Coursework 平台下载的电子论文。有些文献需要精读全文，有些只需阅读摘要以了解特定流派学者的思考视角，具体要求会在布置时明确说明。 --- ### [49:47](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2987s) 课程平台、讲义无纸化与助教团队 Sapolsky 详细说明了网络平台（Coursework）上的资源配置。平台上将提供讲义备份、常见问题答疑（Q&A）、课程事务通知以及讲座幻灯片。Sapolsky 本人还亲自为学期前半段的每堂讲座撰写了约 5 至 10 页的详尽讲义，但他坦言随着学期推进自己可能会“精疲力竭”，因此后半学期将不再提供这套详尽笔记。对于旁听或未正式注册的学生，课程团队也正在寻找让他们获取在线资源的方法。 从下次课起，讲义将全面停止纸质发放。全班每次讲座如果打印双面讲义，将消耗约 5,000 张纸，因此材料会在前一天上传至 Coursework；对于少数不习惯看屏幕的学生，他笑称如果是“斯坦福最后一个脱离电脑屏幕无法生存的人”，可以私下来找他领取特例打印版。 此外，由于上一个时段的课程人数规模极大，进出教室的人流在门口形成严重拥堵，Sapolsky 建议后续来上课的学生统一从阶梯教室顶部的门进入，顺着台阶顺畅向下流动，顺势把上一堂课还没走出去的学生“赶出”教室。随后，Sapolsky 让在场的助教（TAs）起立亮相：“TAs, stand up and be embarrassed.” 助教团队成员大多修读过本课程甚至曾经担任过助教，各自专精于行为生物学的不同细分领域。几周之后，小班讨论将分流为常规巩固班与面向进阶背景学生的提高班。 --- ### [52:52](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=3172s) 学分内幕轶事与课堂录像安排 在提问答疑环节，有学生询问该课程为何设置为 5 个学分（units）。Sapolsky 解释这是因为每周面授课时非常长，接着他爆料了一段关于学分的大学行政内幕。该课程在过去有一段时间曾被评定为 6 个学分，这直接源于时任斯坦福教务长（Provost）的康多莉扎·赖斯（Condoleezza Rice）。 Sapolsky 回忆道，当年赖斯在极其苛刻的条件下大幅提高了生物系教授的教学工作量要求，“彻底把生物系整惨了”（totally screwed the biology department）。为了反制，全系教授串通一气，使尽了各种“见不得光的把戏”来虚报和注水各自课程的学分量，于是这门 5 学分的课被生生拔高到了 6 学分；直到后来校方发现了其中的猫腻，这项操作才被叫停。Sapolsky 随即讽刺道：“So first she did that, and then weapons of mass destruction.” 引发全场大笑，他还打趣让学生如果在校园里碰见赖斯代他问声好。 - **学分与负担**：目前的 5 学分设定符合其实际工作量与密集的授课时长。 - **课堂录像上线**：每堂课的录像都会在课后一天左右上传至 Coursework。因为两小时的连排大课经常会导致学生与其他课程发生时间冲突，在线录像能方便不得不缺席其中一小时的学生自主补课。 - **片尾互动**：讲座临近尾声时，Sapolsky 还关切地向台下之前带食物的学生确认：“Bagel guy. Did you get your bagel, or did somebody eat it?” 得知对方顺利吃到了百吉饼后，全场在轻松的气氛中结束了本节课程。 ### [54:30](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=3270s) 考试时间与考核形式安排 在课程进入答疑环节后，学生们首先关心的核心事务是期中与期末考试的时间及形式。Robert Sapolsky 教授起初记不清具体日期，引来台下一阵笑声，随后确认期中考试定于 5 月 3 日（周一）晚间 7:30，期末考试则定在 6 月 4 日。面对学生关于考试题型的提问，Sapolsky 幽默地反思了课程理念与现实操作之间的冲突。按照课程彻底打破“思维框架/分类分类”（buckets）的理想设想，考核形式本应是长篇论文，甚至要求学生写十四行诗、就下丘脑创作细腻感性的俳句；然而面对庞大的选课人数，为了避免助教团队（TAs）在短时间内批改海量试卷而彻底崩溃，课程只能退而求其次，采取包含大量选择题的形式，寻找“最低公倍数”以维持评分的可操作性。 在学术侧重点上，期中考试与期末考试有着截然不同的考查目标：期中考试主要是打好基础，检验学生是否扎实掌握了各个学科框架内的基本事实，附带少量跨学科思考；而期末考试则将重心完全转移到跨学科整合上，强制要求学生串联不同领域。Sapolsky 总结了两者在智力导向上的区别：“Midterm-- have the facts down. Hopefully it won't be quite as mindless as that, but that's the main function of the midterm.” ```mermaid flowchart LR accTitle: 考核重点对比 accDescr: 展示期中考试与期末考试在考核重点和思维要求上的差异 subgraph Midterm["期中考试 (5月3日)"] M1["掌握各领域核心事实"] --> M2["初步尝试跨学科思考"] end subgraph Final["期末考试 (6月4日)"] F1["打破思维分类与框架"] --> F2["全方位跨学科整合应用"] end ``` - **期中考试时间**：5 月 3 日，星期一，晚上 7:30。 - **期末考试时间**：6 月 4 日，时长两小时。 - **考核题型**：以多选题（Multiple-choice questions）为主，兼顾助教评分负荷与基础知识覆盖面。 - **教学重心划分**：期中重在掌握各个分支学科的事实细节；期末侧重打破分类框架、跨越学科边界进行综合思考。 ### [56:10](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=3370s) 辅导课录制与期末考试具体时间修正 随后，学生就辅导课（catchup section）的资源共享形式进行了确认。Sapolsky 现场向助教团队核实，助教确认辅导课将进行音频录制，随后会上传至斯坦福的 Coursework 平台。除了录音之外，任何关键的讲义、视觉图表等辅助材料也都会同步发布到该系统，以便学生随时查阅复习；后续三次讲座的相关材料也会提前发放到位。 在解答考试具体时间段的追问时，现场出现了一点关于期末考试开始时间的小波折。Sapolsky 先是将期末时间误说成晚间 7:30，随后改口为 5:15，经学生纠正提醒后，最终明确修正为下午 12:15 开始，时长两小时。Sapolsky 将正确的时间写在黑板上以确保全班知晓，并在确认无其他问题后结束了本次导论课程的答疑环节。 - **辅导课资源**：现场进行音频录制，并连同重要讲义与图表上传至 Coursework 教学平台。 - **讲座资料预发**：未来三节课的配套资料将提前发放给学生。 - **期末考试最终确认时间**：6 月 4 日中午 12:15 开始，考试时长为 2 小时。 ## Notable quotes > [11:42](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=702s) Thinking in categories makes it easier for us to remember stuff. — Robert Sapolsky > [12:44](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=764s) So we see one of the dangers there, which is when you are paying too much attention to categories, you can't differentiate two facts that fall within the same category. — Robert Sapolsky > [15:01](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=901s) And what we see there is the third example, which is when you pay too much attention to boundaries, you don't see the big picture. — Robert Sapolsky > [23:22](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=1402s) 在这一层面上，根本就不存在所谓的水桶。它们不过是临时的平台，而每个平台仅仅是用来描述在此之前发生的一切——从数千年以前的进化开始——所产生结果的最轻松、最便捷的方式。 — 罗伯特·萨波尔斯基 > [46:24](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2784s) Behavior is not like a clock. Behavior is like a cloud. And you don't understand rainfall by breaking a cloud down into its component pieces and gluing them back together. — Robert Sapolsky > [44:29](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=2669s) Because the obvious argument I would make is everybody has to learn behavioral biology because we're being behavioral biologists every time we serve on a jury. — Robert Sapolsky > [03:17](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=197s) 有时候，你身体里发生的生理变化，会剧烈影响你的大脑活动。 — 罗伯特·萨波尔斯基 > [03:17](https://www.youtube.com/watch?v=NNnIGh9g6fA&t=197s) 有时候，你脑子里的想法会波及身体的每一个哨所。 — 罗伯特·萨波尔斯基 ## Mentioned Robert Sapolsky, John Watson, B. F. Skinner, Egas Moniz, Konrad Lorenz, Dan White, Harvey Milk, James Gleick, Condoleezza Rice, Stanford University, Wellesley College, Safeway, Coursework, Chaos, Baby Beluga ## Video description (March 29, 2010) Stanford professor Robert Sapolsky gave the opening lecture of the course entitled Human Behavioral Biology and explains the basic premise of the course and how he aims to avoid categorical thinking. Stanford University http://www.stanford.edu Stanford Department of Biology http://biology.stanford.edu/ Stanford University Channel on YouTube http://www.youtube.com/stanford [Source](https://www.youtube.com/watch?v=NNnIGh9g6fA)

[11:42] Robert Sapolsky: Thinking in categories makes it easier for us to remember stuff. [12:44] Robert Sapolsky: So we see one of the dangers there, which is when you are paying too much attention to categories, you can't differentiate two facts that fall within the same category. [15:01] Robert Sapolsky: And what we see there is the third example, which is when you pay too much attention to boundaries, you don't see the big picture. [23:22] 罗伯特·萨波尔斯基: 在这一层面上，根本就不存在所谓的水桶。它们不过是临时的平台，而每个平台仅仅是用来描述在此之前发生的一切——从数千年以前的进化开始——所产生结果的最轻松、最便捷的方式。 [46:24] Robert Sapolsky: Behavior is not like a clock. Behavior is like a cloud. And you don't understand rainfall by breaking a cloud down into its component pieces and gluing them back together. [44:29] Robert Sapolsky: Because the obvious argument I would make is everybody has to learn behavioral biology because we're being behavioral biologists every time we serve on a jury. [3:17] 罗伯特·萨波尔斯基: 有时候，你身体里发生的生理变化，会剧烈影响你的大脑活动。 [3:17] 罗伯特·萨波尔斯基: 有时候，你脑子里的想法会波及身体的每一个哨所。

[45:36] Robert Sapolsky: Behavior is like a cloud. And you don't understand rainfall by breaking a cloud down into its component pieces and gluing them back together. [13:27] Robert Sapolsky: When you put up boundaries, you have trouble seeing how similar things are on either side of it. [33:59] Robert Sapolsky: Some of the time, we are just a plain old off-the-rack animal.

[0:00] [MUSIC PLAYING] [0:04] Stanford University. [0:09] This is BIO 150, isn't it? [0:12] OK, just wanted to make sure. [0:15] So we start off with a scenario. [0:18] 40-year-old guy-- quiet, suburban life. [0:22] Married 15 years, two kids, 3.5 dogs. [0:27] Everything's standard. [0:28] Everything's going wonderfully. [0:29] And one day out of nowhere, he punches somebody [0:33] in the face at work. [0:35] Totally bizarre, out of character. [0:37] The guy is standing there by the water cooler [0:40] and makes some comment on some baseball team, [0:42] takes exception to it, punches him in the face. [0:45] Utterly strange. [0:47] Things are quiet. [0:49] Three months later, his wife of 15 years happy marriage [0:52] discovers he's having an affair with a 16-year-old checkout [0:55] kid down at the Safeway. [0:57] Really weird. [0:58] Then three months after that, he absconds [1:02] with all the money at work, embezzles it, disappears, [1:04] and is never seen again. [1:06] Three possibilities. [1:08] First one-- this guy is a truly deep creep. [1:12] Second, he is having the most immature midlife [1:15] crisis you could ever imagine. [1:17] Third possibility-- he has a mutation [1:20] in one gene in his head. [1:22] And what we will be seeing is this [1:24] is exactly the profile that you get [1:26] in a certain neurological disease [1:29] where it's one gene that's out of whack. [1:31] First demonstration of that. [1:33] OK, just to get a sense of who's here, [1:36] how many of you think there is a genetic influence [1:40] on sexual orientation? [1:43] OK, how many think it is possible for prenatal events [1:47] to influence your political opinions 30 years later? [1:53] OK, how many think that there is a valid way of using biology [1:58] to understand who's religious and who isn't? [2:02] Not quite as many hands there. [2:04] OK, as long as we're in that terrain, [2:06] how many people believe in God? [2:09] How many people believe in souls? [2:12] How many people believe in evil? [2:19] How many people believe in free will? [2:24] That's going to change. [2:25] [LAUGHTER] [2:28] Oh, I might as well ask. [2:29] Is there anybody in this room who actually [2:31] does believe in evolution? [2:35] Just wanted to make sure. [2:36] See what we're dealing with here. [2:38] OK, how many think that there is a genetic influence [2:41] and that there is a basic biological difference, sex [2:45] difference, in levels of aggression? [2:49] How many think there's biological basis of sex [2:51] differences in intelligence? [2:55] OK, who thinks it's all explained by nature? [3:00] Who thinks it's all explained by nurture? [3:02] Who thinks there's a magnificent, fascinating, [3:06] nuanced interaction between nature and nurture? [3:08] [LAUGHTER] [3:09] Yay. [3:10] OK, well everybody's going to get an A+ then. [3:14] You already have the course under control. [3:17] So we start off trying to find something in common. [3:22] Look at these four events here-- or not, [3:27] in terms of being scraped out there. [3:28] But these are four circumstances that have [3:30] something surprising in common. [3:33] Having your period. [3:35] Having a brain tumor. [3:38] Eating a lot of junk food. [3:40] Taking anabolic steroids. [3:42] Those of you who are not oriented [3:43] to with, that's the ones that build up your muscles [3:45] like testosterone derivatives. [3:47] OK, these all have something in common-- having your period, [3:51] having a brain tumor, eating a lot of junk food, [3:53] and taking a lot of anabolic steroids. [3:56] Anybody want to fathom a guess what's the commonality [3:59] amongst the four of them? [4:01] Yeah. [4:02] Hormones? [4:03] Hormones. [4:04] Good. [4:04] OK, we're off and running with hormones. [4:07] Good. [4:07] Even more specific than that. [4:10] Something they all have in common. [4:13] Oh, come on, somebody want to guess? [4:17] I see these brief movements of hands [4:19] there as people change their mind. [4:22] OK, it all has to do with hormones. [4:25] They all have hormones in common, [4:26] I say, trying to facilitate somebody making the next guess. [4:29] Oh, come on. [4:30] They all have something. [4:32] OK, we gotta get outta here at some point. [4:34] These all have four things in common. [4:36] All of these have been used successfully in courts of law [4:40] to explain the behavior of a murderer. [4:44] [LAUGHTER] [4:47] In the first case, a number of cases [4:52] where the fact that a woman was having [4:55] her period at the time of killing someone [4:57] was part of what a jury said led them to exonerate the person. [5:01] A literature showing that a disproportionate share [5:04] of female aggression comes around the time of menses. [5:08] Next one-- there is an area of the brain you will know so much [5:12] about over the next three months called the amygdala [5:15] that has something to do with aggression [5:18] and has something to do with fear. [5:20] And you get a brain tumor there, and in a number of cases, [5:23] you get someone who is uncontrollably violent. [5:26] And this has also been used successfully in a court of law. [5:30] Junk food-- any of you who are San Francisco history buffs [5:34] will know 20 years ago, 30 years ago [5:37] that Dan White, a disappointed office seeker, [5:41] assassinated the mayor of San Francisco along with Harvey [5:44] Milk. [5:44] And as part of his remarkably successful defense [5:48] for a double murderer that led to a remarkably short jail [5:51] sentence, was the famed Twinkie defense. [5:54] The argument that his addiction to junk food [5:58] caused wild fluctuations in his blood sugar levels, [6:01] which caused him to do that. [6:03] Finally, anabolic steroids. [6:06] Any number of cases of people having uncontrolled violence [6:09] arguing because they were weight lifters and a wildly [6:12] abusive range of taking this stuff [6:14] had something to do with violence. [6:16] Put all four of these together, and we [6:18] get the first of the two points of this entire course. [6:22] Which is, sometimes the stuff that's going on in your body [6:26] can dramatically influence what goes on in your brain. [6:30] Second critical point-- tonight, when you've settled back down, [6:34] and you're ready to go to sleep, and you're nice and relaxed, [6:37] and your heart's beating nice and slow, [6:39] think the following thought. [6:40] You know, that heart isn't going to beat forever. [6:45] Think about your lips turning blue after. [6:49] Think about the blood flow slowing down. [6:51] Think about your feet and your toes getting cold. [6:54] And at that point, you will probably [6:56] be increasing the rate at which that heart beats. [6:59] And you will have just seen the second key thing [7:01] in this course, which is sometimes [7:04] what's going on in your head will [7:06] affect every single outpost in your body. [7:09] And what this course is about is the intertwining, [7:12] the interconnections between your physiology [7:15] and your behavior-- the underlying emotions, [7:18] thoughts, memories, all of that, and the capacity of each [7:22] to deeply influence the other under all sorts [7:25] of circumstances. [7:27] Now, what we're going to be doing with this [7:28] is trying to understand this under fairly [7:31] difficult circumstances. [7:32] If everybody here was here because they really [7:36] wanted to understand why all the wildebeest on earth [7:39] mate in the same week each year, we'd [7:42] have a fighting chance of figuring that one out. [7:44] But that's not what we want to understand. [7:46] We don't want to understand why birds [7:48] migrate and don't get lost. [7:50] We want to understand human behavior. [7:53] Worse than that, harder than that, human social behavior. [7:57] And hardest of all in some cases, some grossly abnormal [8:00] human behavior. [8:02] And if you're going to try to do that, there [8:04] is a problem which is, officially, it's complicated. [8:08] It is a huge, messy process trying [8:10] to make sense of the biology of human social behavior. [8:14] And just as all sorts of realms when [8:17] one deals with messy, complicated problems [8:20] that you need to think about in some wildly interacting way, [8:23] we all have a strategy that we come up with. [8:27] A strategy to make things easier-- which [8:30] is that we think in categories. [8:33] We think in categories. [8:34] We take things that are continua, [8:36] and we break them into categories. [8:38] And we label those categories. [8:41] And we do that in various settings [8:43] because it could be extremely useful. [8:46] For example, somebody give me an estimate on how long [8:51] this line is. [8:52] [INAUDIBLE] [8:55] A foot. [8:56] OK, people who said a foot, what is it that [8:59] went through your head to figure it out? [9:02] You imagined how long a ruler is. [9:05] Is this 11.5 inches because and it's 11 inches-- an 8.5 by 11. [9:11] But everybody in here has this category in their head things [9:15] that are kind of the same length as a ruler. [9:19] A continua of lengths, and there's a category for that. [9:22] Suppose I'm telling you I have some friend who's a runner. [9:25] He runs the mile. [9:26] He's incredibly fast. [9:28] In fact, he's one of the best runners [9:29] in the country at this point. [9:31] How fast does he have to have run the mile or better for you [9:34] to be deeply impressed? [9:36] Under four minutes. [9:38] And thus, we have another categorical boundary [9:40] there of there's an infinite variety of speeds [9:44] with which you can run a mile. [9:45] Yet we have in our heads this boundary-- people [9:48] who are under four minute milers, [9:51] you are very impressed with. [9:53] OK, now I want to impress you with another friend of mine [9:56] who's a painter. [9:57] And this person is such a great painter [9:59] that they paint with 11 different colors. [10:03] That doesn't work because that's not a category that we have. [10:06] We don't classify the quality-- hopefully [10:09] not-- we don't classify quality of paintings along those lines. [10:14] But we begin to see here is in the right areas, [10:17] we have categories that we impose on things [10:21] that are not categorical. [10:23] Here's an example. [10:24] Why should you do this? [10:26] Where'd the example go? [10:27] Here's one of the classic continua [10:29] that we ever deal with, which is the continua of color-- [10:32] the varying wavelengths that take the rainbow from violet [10:36] to red. [10:36] And there's an infinite number of spaces in between. [10:39] And what do we do? [10:40] We have rules in English that you can divide the continua [10:44] here and here, or whatever, and that's what you call a color. [10:49] This is red. [10:50] Everything from here is red. [10:52] Everything here is orange, so on. [10:54] You take a continua, and you break it into boundaries. [10:57] Why do we do that? [10:59] Because it makes it easier to store the information away. [11:03] Instead of remembering the absolute features of something, [11:06] you simply say, it's a. [11:08] It's a sub-four minute miler. [11:10] It's a line that's about the length of a ruler. [11:14] It's the color orange. [11:16] How do you know that's the case? [11:18] Because go and take people from other language groups, [11:20] where their language arbitrarily divides the rainbow [11:24] at other points with completely different color terms, [11:27] and they remember different profiles of colors differently [11:31] than an English speaker might. [11:33] Take a color. [11:34] And if the color comes right in the center of somebody's color [11:40] characterization, if it comes right [11:42] in the middle of the range of what counts as that color, [11:45] people remember whether they saw that color or not far better [11:49] than if you show them a color at the boundary. [11:52] And people will show that as a function of what language [11:55] they speak. [11:56] Taking a continua, and you break it into pieces, [11:59] because it's easier to deal with the facts. [12:01] Another example of it. [12:02] Here we have four objects. [12:05] And as drawn here, simply because we have categories [12:09] to describe the first three, do one [12:11] of those tests of show people a bunch of shapes, [12:14] and they come back an hour later and ask them, [12:15] Have you seen this shape before? [12:17] And people are going to be far more accurate with this [12:20] than whether they saw this or not because we [12:23] don't have a word for it. [12:24] We don't have a word that's at all sort of analytical [12:27] that some squiggly whatever. [12:29] We don't have a clear cut category. [12:31] Thinking in categories makes it easier [12:34] for us to remember stuff. [12:36] And it makes it easier for us to evaluate stuff. [12:38] So that's a classic sort of response [12:41] that we have cognitively to complicated things. [12:44] But there's a bunch of problems with categorical thinking. [12:48] First example-- and first one you [12:51] can see from a realm of language differences-- [12:54] in that not only is there a continua of infinite number [12:57] of wavelengths, there is a continua of sounds [13:00] that humans can make. [13:02] And different languages draw boundaries at different points [13:05] as to what count as similar sounds or different sounds. [13:09] There's like two different T-H sounds in English, [13:12] which apparently we're not very good at hearing. [13:15] But there's other ones we are. [13:16] And that will affect your ability [13:18] to remember stuff-- what word it was-- depending on [13:22] whether it is on a dramatically different boundary, whether it [13:25] is a sound that sounds different to you or not. [13:27] Example of this-- apparently in Finnish, people [13:32] do not differentiate between the sound of a B [13:35] and the sound of a P, whereas we have no trouble with that. [13:38] But people from Finland do not make that differentiation. [13:41] And I discovered this one day a number of years [13:43] ago where, for reasons I don't even understand, [13:46] I found myself needing to take to testicular biopsies [13:49] on baboons. [13:52] Not having sort of learned that in junior high how you do that, [13:55] I called up this guy at urology the med school [13:57] who happened to be Finnish. [13:59] And I explained to him what I wanted to do. [14:01] And he sort of took me through the paces [14:03] and told me what thingy I needed to buy, and that sort of stuff, [14:07] and holiday packages of those where you can get a dozen. [14:10] And sort of telling me how to do that. [14:12] And once we went through he said, What I want you to do, [14:15] the thing to do at this point, is get some practice. [14:18] I want you to practice on a bear. [14:21] [LAUGHTER] [14:22] And I said, What? [14:24] He said, Yeah. [14:25] Practice on a bear. [14:27] And I said, Are you kidding me? [14:29] He said, I know. [14:30] I know it sounds crazy, but we have all the residents do that. [14:33] It's a very good learning device. [14:36] Either practice on a bear or an apple. [14:40] Oh. [14:41] Oh. [14:42] Here we see the dangers of making mistakes [14:45] about differences between B and P under certain circumstances. [14:50] So we see one of the dangers there, [14:52] which is when you are paying too much attention to categories, [14:56] you can't differentiate two facts that [14:59] fall within the same category. [15:01] Next example. [15:02] I remember back at various points of anxiety during exams, [15:06] and such back when where there was [15:08] a world of difference between getting a 65 on a test and a 66 [15:13] on a test. [15:14] Not particularly different. [15:15] But because there is this boundary drawn there [15:18] between passing and failing, there is this dramatic [15:21] differentiating we make. [15:23] When you put up boundaries, you have [15:24] trouble seeing how similar things are [15:27] on either side of it. [15:29] Next example, one additional problem [15:32] that you get when you think categorically. [15:34] And for this, everybody needs to turn [15:36] over one of the pieces of paper-- [15:37] the paper you're going to hand in, the questionnaire. [15:40] And what I'm going to do is read you a series of phone numbers, [15:44] and I want you to write them down as accurately as possible. [15:50] OK, ready? [15:52] 243-2649, 650-3260, 256-5779, 832-2449, 291-3171, 231-4026, [16:08] 593-2449, 743-8840, 831-5287. [16:18] OK. [16:19] Now what that exercise is-- and no, [16:22] that doesn't count towards the grade. [16:24] What that will show, I'm sure, when [16:27] in some obsessive burst of procrastination [16:29] I actually look through the answers [16:31] tonight, what it's going to show is the accuracy [16:34] is going to tank the second you go from the phone number [16:37] pattern of three digits followed by four, break up that pattern. [16:42] And suddenly we all get screwed up because we're saying, [16:44] Wait a second. [16:45] I thought it was a phone number. [16:46] That was one digit. [16:47] Now two digits. [16:48] I can't. [16:49] And it's gone, and you're on to the next one. [16:51] And what we see there is the third example, which [16:54] is when you pay too much attention to boundaries, [16:57] you don't see the big picture. [17:00] All you see are categories. [17:02] All you see are, Wait a second, phone numbers [17:05] are supposed to come with three digits followed by four. [17:08] Another example where we use categorical thinking. [17:11] OK, I'm putting up a number series here. [17:20] OK. [17:21] What's-- oh, my god. [17:26] OK, what's the next number in this series? [17:31] And why? [17:31] [INAUDIBLE] [17:34] 42. [17:35] How come? [17:36] [INAUDIBLE] [17:42] OK, so we're kind of oscillating all over the place there. [17:47] OK, so that's as valid as anybody else's. [17:51] Who else has a next number in line there? [17:53] [INAUDIBLE] [17:54] What's that? [17:54] [INAUDIBLE] [17:55] 45. [17:56] How come? [17:56] [INAUDIBLE] [18:03] OK. [18:03] Are you going to take that? [18:06] 45. [18:07] That's very-- OK. [18:08] What else? [18:08] Let me make it a little bit easier here. [18:17] OK. [18:18] So what's the next number in that series? [18:20] And what I'm telling you is if you think [18:23] about the world with a certain set of categories in your head, [18:27] you will know the next number in the sequence. [18:29] So what's the next one? [18:30] [INAUDIBLE] [18:32] Seven billion. [18:33] [INAUDIBLE] [18:37] OK. [18:38] That one. [18:40] OK. [18:41] Seven billion. [18:42] That's another possibility. [18:44] Although presumably, it would be seven billionth. [18:47] Anything else? [18:48] Any other guesses here as to what happens next? [18:51] 4th, 14th, 23rd, 34th. [18:54] What's the next one in the sequence yes? [18:56] [INAUDIBLE] [18:57] 44. [18:57] How come? [18:58] [INAUDIBLE] [19:11] OK. [19:12] But remember, it's got to be 44th. [19:15] What's that? [19:16] Ordinal? [19:16] Cardinal? [19:17] Whatever it is. [19:17] What? [19:18] 42nd. [19:19] How come? [19:20] The subway? [19:21] You were right. [19:22] You were right. [19:23] Anybody who is a New Yorker will know what the next one is. [19:29] These are the subway stops. [19:31] And you get a bagel with cream cheese. [19:33] [APPLAUSE] [19:43] So you get New Yorkers, and while everybody else [19:46] is thinking logical things like 43, and 41, and 45, [19:50] and seven billion, and all of that, [19:52] you've got this whole world of dividing numbers by. [19:55] Subway stops. [19:56] We think in categories. [19:58] We think in categories. [19:59] But as you just saw, there are these problems. [20:02] First one being, when you think in categories, [20:05] you underestimate how different two facts are when [20:08] they fall in the same category. [20:10] When you think in categories, you [20:12] overestimate how different they are [20:15] when there happens to be a boundary in between them. [20:18] And when you pay attention to categorical boundaries, [20:20] you don't see big pictures. [20:22] Now, what our goal in this class is going to be is [20:25] think about this big, complex issue [20:28] of the biology of behavior without falling [20:30] into thinking in categories. [20:32] What do I mean in this regard? [20:34] Thinking categorically about a subject like this? [20:36] There's some chicken. [20:39] And the chicken is standing somewhere. [20:41] And there's some rooster over there [20:43] that does some sexually solicitive, exciting thing [20:47] for the female. [20:48] And in response to that, the female [20:50] picks up and goes running over to the rooster. [20:53] And thus, we have our first behavioral biology question [20:56] here. [20:56] Why did that chicken cross the road? [20:58] To get to that rooster. [21:00] So you could answer that like an endocrinologist [21:03] and say, Well the female had certain levels of estrogen [21:05] in her bloodstream, which made this key hypothalic areas [21:08] responsive to the stimulus. [21:10] Or you could answer it like an anatomist, [21:12] saying, Well, because the fulcrum of her pelvis [21:15] or whatever it is chickens have that allow them to run. [21:18] Or you could answer it in the category [21:20] of an evolutionary biologist. [21:22] That over the millennia, chickens [21:24] that didn't respond to sexually solicitive gesture from males [21:27] left fewer copies of their genes. [21:29] And there's all these different categories [21:31] that we can use to explain what's going on. [21:34] All of these different buckets. [21:37] All of these different buckets which [21:38] begin to pull you towards all of the problems we just saw. [21:43] Now, having trouble telling how different or similar two facts [21:46] are. [21:47] Having trouble seeing big pictures. [21:49] Over emphasizing the importance of the bucket [21:52] you happen to live inside of. [21:54] And thus, suddenly everything about this behavior [21:57] is explained by a gene, a neurotransmitter, a childhood [22:02] trauma, a living inside one bucket. [22:05] Whet we are going to be doing over and over in here [22:08] as the main point of the course is looking at how what goes on [22:11] in your body influences behavior, emotions, memories. [22:14] How what goes on there influences your body, [22:16] looping over. [22:17] And at every one of those points, [22:19] resisting the pull to think categorically. [22:22] Oh, this is the explanation for where this behavior came from. [22:27] Here's what we're going to be doing instead [22:29] throughout in terms of the structure of the class [22:31] when we get to actual behaviors. [22:33] For each behavioral category, we will start off [22:37] by looking at what the behavior looks like. [22:39] Because often, that takes a lot more objectivity [22:42] than we initially assume. [22:44] What does the behavior look like? [22:46] Then we will say, Well, what went on in that organism [22:49] a half second before that behavior occurred [22:53] to cause it to occur? [22:54] Which is the world of what's going on with neurons. [22:57] What's going on with circuitry. [22:59] Where's the explanation for the behavior. [23:02] Aha. [23:02] This behavior happened because this part of the brain [23:06] got activated. [23:07] But just as we're about to settle in happily [23:09] into that bucket, we push back a bit [23:11] and say, Well, what smell, what sound, [23:15] what sensory stimulation in the environment [23:18] caused those neurons to get activated [23:20] and produce that behavior? [23:22] And then pushing one step further behind. [23:24] OK, well, what do hormone levels, various hormones [23:28] in the bloodstream of that animal or individual [23:30] for the past few hours, how do those hormones [23:33] change how sensitive you are to those sounds, smells, [23:37] et cetera, that cause those neurons [23:39] to get activated and produce the behavior? [23:41] And all we're going to be doing is working our way back, [23:44] all the way through early development, fetal life, [23:47] the genetic makeup up of an individual, the genetic makeup [23:50] up entire populations, species, the evolutionary pressure [23:54] on, all the way back to there. [23:56] How do you explain each one of these behaviors [23:59] in the context of those outposts? [24:01] And how are they not really outposts? [24:04] All they are, are different ways of expressing [24:07] the same biological influences. [24:09] If you say, Ooh, here's a hormone [24:12] that explains this behavior. [24:13] This behavior is caused by Hormone X. Hormone [24:17] X is coded for by a gene. [24:19] So suddenly you're not just talking about endocrinology. [24:22] You're talking about genetics. [24:23] And if there's a gene there, it has [24:25] been the subject to selection. [24:27] So suddenly you're talking about evolution. [24:29] If you were talking about what smells, sights, et cetera, [24:33] are the acute triggers for a behavior, [24:35] by definition you're also talking [24:37] about fetal development that determined [24:39] how sensitive those systems were to those sorts of stimuli. [24:43] What we're going to be having over and over again is [24:46] any one of these buckets that we spend some time in, [24:50] all we're going to do is think of that bucket is at that point [24:54] the most convenient way of describing [24:57] all of the influences that came beforehand. [25:00] And in that regard, there's no buckets. [25:03] All they are, are temporary platforms. [25:05] And each platform is simply the easiest, most convenient way [25:10] of describing the outcome of everything that came beforehand [25:14] starting with millennia back in evolution. [25:18] OK. [25:18] So that sounds great. [25:20] That's what we're going to do. [25:21] We're going to do this. [25:22] And we're going to be very sophisticated and fancy [25:25] in our thinking about it. [25:26] And we're not going to fall for categorical thinking. [25:29] OK, this is a complicated subject, and we're smart. [25:32] So we're going to try to think about it smartly. [25:34] That's great. [25:35] But like maybe this is just an irritating song and dance here [25:39] of, Ooh, we're not going to fall for categorical thinking [25:42] like people out there. [25:43] Obviously when people are thinking [25:45] about stuff like behavior, and they do this professionally, [25:48] professional biologists, yes, and they understand also. [25:53] This is just the strawman. [25:55] Ooh, we're going to be more sophisticated in our thinking [25:57] than endocrinologists, and geneticists, and all of those. [26:01] They obviously know that these things interact, [26:04] and there's not just one explanation. [26:06] And it's just the area they focus on. [26:08] They understand that. [26:09] Let me read you a few quotes to show [26:12] just how much some of these folks don't understand that. [26:17] First quote. [26:19] "Give me a child at birth from any background, [26:22] and let me control the total environment in which he [26:25] is raised, and I will turn him into anything [26:27] I wish him to be-- whether doctor, lawyer, [26:30] or beggar, or thief." [26:32] This was John Watson, 1912, one of the founding fathers [26:36] of the school of psychology called behaviorism. [26:40] Behaviorism-- that sort of reached its apogee [26:42] with this guy BF Skinner in the 1950s. [26:45] This notion that if you could control [26:47] the rewards, the punishments, the positive, [26:49] the negative reinforcements, you could turn anybody [26:52] into anything you want, whether doctor, lawyer, beggar, [26:55] or thief. [26:56] And we know that isn't the case. [26:59] We know that's not possible. [27:01] We know that. [27:02] All you have to do is throw in one other factor [27:05] and like a lot of protein malnutrition during fetal life, [27:08] and you're not going to be able to do that. [27:11] That being a crude example of just how wrong this guy was. [27:14] You cannot have all the control over the environment and turn [27:18] somebody into whatever you want. [27:20] Here's a guy living pathologically in this bucket [27:24] that behavior could be explained solely by understanding reward [27:27] and punishment. [27:29] Interesting factoid-- this John Watson guy. [27:31] Shortly after that, he was driven out [27:33] of academia for a wild scandal that he was involved in. [27:37] And he spent the rest of his career [27:39] apparently as an extremely successful advertising [27:42] executive. [27:43] Going to show you something-- he may not [27:44] have been able to turn people into anything [27:46] he wanted, but apparently he could [27:47] make them buy all sorts of geegaw nonsense. [27:50] OK, next quote. [27:52] "Normal psychic life depends upon the good functioning [27:56] of brain synapses." [27:58] If you don't know what synapses are, don't panic at this point. [28:01] They're ways brain cells connect with each other. [28:04] OK. "Normal psychic life depends on the good functioning [28:06] of brain synapses, and mental disorders [28:09] appear as a result of the synaptic derangements. [28:12] Synaptic adjustments will then modify the corresponding ideas [28:17] and force them into different channels. [28:19] Using this approach, we obtained cures and improvements [28:22] but no failures." [28:25] Synaptic adjustments. [28:27] What do you suppose those little old synaptic adjustments are [28:31] that this guy is referring to? [28:32] Any guesses? [28:33] [INAUDIBLE] [28:36] Somebody shout it out. [28:37] [INAUDIBLE] [28:38] Electroshock therapy. [28:40] Electroshock therapy-- you know, a little synaptic. [28:43] You wish it were as gentle as electroshock therapy. [28:47] This is even more dramatic synaptic adjustments. [28:50] Any other guesses? [28:51] [INAUDIBLE] [28:52] Yeah, frontal lobotomies. [28:54] You want to adjust somebody's synapses, [28:57] so you slice off the front third of their brain or so. [29:01] This was Egas Moniz, a Portuguese neurologist who [29:05] invented frontal lobotomies. [29:07] It had a different name at the time. [29:08] But was the person who started this, [29:10] and something that was done to tens and hundreds of thousands [29:14] of people who had absolutely nothing wrong with them. [29:18] One of the darkest chapters of where psychiatry [29:21] gets in bed with ideology. [29:23] Massive criminal destruction of people's brains. [29:27] This is what he had to say about the procedure on his acceptance [29:31] of his Nobel Prize in Physiology and Medicine [29:33] for having invented it. [29:35] So here we have somebody pathologically [29:37] living in a world of understand how synapses are working, [29:42] adjust them. [29:43] And with that, we obtain cures and improvements [29:46] but no failures. [29:48] Final quote. [29:49] Worst one of all. [29:51] "The selection for social utility [29:54] must be accomplished by some social institution [29:57] if mankind is not to be ruined by domestication [30:00] induced degeneracy. [30:02] The racial idea as the basis of our state [30:04] has already accomplished much in this respect. [30:07] We may, and we must, rely on the healthy instincts [30:11] of the best of our people for the extermination [30:13] of elements of the population loaded with dregs." [30:17] Anybody want to guess who that was? [30:19] [INAUDIBLE] [30:20] Hitler? [30:21] Hitler, that behavioral biologist. [30:23] He was a little bit busy at the time. [30:24] This was instead one of Hitler's main scientific propagandists. [30:29] This was somebody living pathologically in a box-- [30:33] a box that doesn't even exist-- having notion of race, [30:37] and ethnicity, and genetics, and all of that, [30:41] saying let me fix that one. [30:43] Let me exterminate the elements of the population loaded [30:46] with dregs, and I'll fix up that little problem of fixing [30:49] something that ain't broken. [30:50] Who was this? [30:51] This was a scientist named Conrad Lorenz. [30:55] Conrad Lorenz, who probably a lot of us are familiar with. [30:58] Conrad Lorenz was one of the founding fathers of ethology. [31:01] We'll learn all about that. [31:02] But he, like everybody knows him winding up [31:05] in all the little kid nature books, [31:07] Conrad Lorenz discovered imprinting in birds. [31:10] And he'd be going around. [31:11] He was this little Austrian guy with this cherubic white beard. [31:14] And he'd always have these little Austrian shorts [31:16] and suspenders. [31:17] And there would be a whole bunch of duckies following him [31:20] because they thought he was mom, and he was totally [31:22] charming and irresistible. [31:24] This sort of old imprinting with his ducky kids. [31:28] And he also happened to be a rabid Nazi propagandists who [31:32] went to his grave saying that there was [31:35] nothing wrong with what he did. [31:37] These are not crappy, fourth-rate scientists. [31:41] These are not people working at the University of the Desert [31:45] of Podunk or whatever. [31:47] These are among the most influential scientists [31:50] of the last century. [31:52] These are people who influenced how people were educated, [31:55] and when we decided it wasn't worth the effort of doing it. [31:58] These are people whose influence led to the brains being [32:02] destroyed of hundreds of thousands [32:04] of people who had nothing wrong with them. [32:06] These are the people who led to the notion [32:09] that you fix up a problem that doesn't exist by exterminating [32:12] nine million people. [32:13] These are not minor scientists. [32:16] These are the most influential people [32:18] of the last century coming out of science in many ways [32:21] living pathologically inside their own buckets [32:25] and how they could explain the entire world. [32:28] And thus, again, our goal is going to not fall for that. [32:33] To think about human behaviors, and in some cases [32:36] to think about some of the most disturbed, [32:38] some of the most frightening, damaged human [32:40] behaviors, and resist the temptation [32:43] to think inside a bucket and find the explanation. [32:47] Again, every level we're going to talk about-- genes, [32:51] hormones, neurons, environmental influence, whatever it is-- [32:54] that point will simply be the easiest way [32:57] of describing all of the influences that came before. [33:01] They're not even temporary buckets. [33:03] There's no buckets. [33:04] That will be our goal. [33:06] Now, in thinking about this and approaching [33:08] human behavior, the biology of human social behavior, [33:11] often the biology of abnormal human social behavior, [33:15] we're going to have three intellectual challenges. [33:18] The first one is recognizing circumstances [33:21] where there is nothing fancy about us whatsoever. [33:25] We are just like every other animal out there. [33:28] And where the challenge is to accept that. [33:30] Let me give you an example. [33:32] You are a hamster. [33:34] You are a female hamster. [33:36] And you're sitting in your cage. [33:38] And, as a female hamster, what you do [33:40] is you ovulate every five days or so. [33:42] And you're going about your business, [33:44] and everything's great. [33:45] Now, somebody puts another female hamster [33:48] in the cage with you. [33:49] And over the subsequent month or so, what happens is both of you [33:54] will begin to lengthen your cycles [33:56] and eventually synchronize them so that you are both [33:59] ovulating the same afternoon on a regular basis. [34:04] Amazing. [34:04] This actually works this way. [34:07] And menstrual ovulatory synchrony-- people [34:09] understand how this works in hamsters. [34:11] It is done with olfaction, with pheromones, [34:14] with chemical airborne signals from one female to another. [34:18] And you can prove this by electrically recording [34:21] from olfactory systems. [34:23] Or, if you don't have much funding, [34:24] you could take like a paper clip over the female hamster's nose, [34:27] and she doesn't synchronize then. [34:29] It's all done with olfaction. [34:30] And what's most amazing is you put the two females together, [34:34] and there is a way of disrupting it. [34:37] Put a male hamster in there, and suddenly the cycles [34:41] desynchronize and shorten, and you break it up [34:43] with male pheromones. [34:45] And what's even more remarkable is you put the two females [34:48] together, and it's not random who synchronizes the other one. [34:53] The dominant female synchronizes the subordinate one. [34:57] Totally understood. [34:58] People have been working on this for years. [35:00] And it works this way in goats, and sheep, and dogs, and cats, [35:06] and pigs. [35:07] Apparently, you could go to a 7-Eleven somewhere in Iowa, [35:11] and you could buy a can of pig ovulatory synchronization spray [35:16] and take it home, and just run wild. [35:18] I have no idea why you would want to do that. [35:21] But nonetheless, that's how you-- [35:23] it's up there with the cans of Cheese Whiz or whatever. [35:27] And it's that well understood. [35:29] And what's remarkable is it works exactly the same way [35:33] in us humans, where it is known as the Wellesley Effect. [35:38] The fact that over the course of freshman [35:41] year, this was first shown in Wellesley, 1970. [35:44] Over the course of freshman year, women-- [35:47] freshman year roommates-- tended to lengthen and synchronize [35:50] their cycles. [35:51] And it was done with olfaction. [35:53] Women who had olfactory deficits didn't synchronize [35:56] with their roommates. [35:57] They would synchronize unless they [35:59] were having close intimate relationships [36:01] with a male, in which case they desynchronized. [36:04] And what's most cruel of all is, it's not random [36:08] who synchronizes to who. [36:10] The studies tend to show is the individual who is more socially [36:14] outgoing, extroverted, dominating, is the one who [36:17] synchronizes the other one. [36:18] And this is well enough understood [36:20] that when I went in college, people [36:22] would sit around at the dinner table and say stuff like, [36:24] Oh, when we roomed together in the summer, [36:26] I had her synchronized by August 1st. [36:30] This is what happens if you hang out with biologists. [36:32] But we're exactly the same. [36:35] The challenge here is recognizing there [36:37] is nothing fancy about us. [36:39] At various points in the class, we [36:40] will look at comparisons between the human and the chimp genome, [36:45] and it's virtually the same. [36:47] Some of the time, we are just a plain old off-the-rack animal. [36:51] Second challenge is going to be circumstances where we appear [36:55] to be just like everybody else, all the other organisms [36:59] out there, but we do something very [37:01] different with the similarity. [37:03] Let me give you an example here. [37:05] You have two humans, two individuals, [37:08] who are going through a ritual. [37:10] They are sitting at a table. [37:12] They're absolutely silent. [37:13] They're making no eye contact, and they [37:16] do nothing more physically taxing than every now [37:19] and then, one of them picks up their hand [37:21] and moves a little piece of wood on the table. [37:24] And if these happen to be the right two [37:26] individuals in the middle of a chess grandmaster tournament, [37:30] these people are maintaining blood pressure [37:33] for six hours running that you only see in a marathon runner. [37:37] These people are going through thousands of calories a day [37:41] doing nothing more than thinking. [37:44] And this is outrageous. [37:46] Because you look at one of these chess [37:48] grandmasters who's just taken down an opponent [37:50] and took their queen, or whatever, [37:52] and they will have the exact same physiology [37:55] as some male baboon on the Savannah [37:57] who's just ripped the stomach open of his worst rival. [38:00] And we're doing it there just with thought. [38:03] And some of the time what's remarkable about us is we [38:05] have absolutely typical, boring physiology, [38:09] but we use it in ways that no other animal could. [38:13] We get stressed by the inevitability of our mortality. [38:17] We get stressed by reading something awful that [38:20] has happened to a child on the other side of the planet. [38:23] We get stressed by somebody zooming past us [38:27] in some sports car, and we decide that we are now [38:29] economically inadequate. [38:31] And you never even see the person's face. [38:33] You just see the car. [38:34] We get stressed reading about something awful happening [38:37] to a character in a novel. [38:40] This is a whole realm of things that we [38:43] could do that nobody else does. [38:44] And on the flip side, we can feel compassion and empathy [38:48] for a loved one. [38:49] But we can also do the same for someone [38:51] on the other side of the planet in a refugee camp. [38:54] We can feel compassion for a member of another species. [38:58] We feel badly when our pets are injured. [39:01] This is another realm where the physiology of the response-- [39:05] the empathy, the emotional bonding, all of that-- [39:08] it's the same boring physiology as every other animal [39:11] out there, and we are using it in a way that [39:13] is unrecognizable. [39:16] Now, some of the time the challenge [39:17] is the third category, which is when we are doing something [39:21] that no other animal out there has [39:23] anything remotely similar to. [39:26] Let me give you an example here, a shocking example. [39:29] You have a couple. [39:31] They live together. [39:32] They come back at the end of the day from work. [39:34] They talk. [39:35] They eat dinner. [39:36] They talk some more. [39:37] They go to bed, and they have sex. [39:38] They talk some more. [39:39] They fall asleep. [39:40] The next day, they do the same exact thing. [39:44] They come home from work. [39:45] They talk. [39:46] They eat. [39:46] They talk. [39:46] They go to bed. [39:47] They have sex. [39:48] They talk some more. [39:49] They do this every single night for 30 days running. [39:53] Hippos would be repulsed by this. [39:56] Because hardly anybody out there in the animal kingdom [39:59] has non-reproductive sex, let alone day after day. [40:02] And nobody else out there talks about it afterward. [40:06] And what we've got here is a whole novel domain [40:09] of human behavior-- language use, aspects of our sexuality, [40:13] this profoundly damaging human uniqueness [40:16] of some individuals confusing aspects of sexuality [40:19] with aggression. [40:21] In some cases, we are going to be out there on our own [40:24] trying to understand what's up. [40:26] OK. [40:26] So that will be the general strategy for the course. [40:29] We will resist categorical thinking [40:31] over, and over, and over. [40:32] Not just because that's cool, and nuanced, and subtle, [40:35] all of that. [40:35] But fall into categorical thinking, [40:38] and you can do unspeakable damage in a realm of science [40:42] that makes the difference. [40:43] We will do so thinking constantly about ourselves [40:47] as a boring species just like all the others out there. [40:50] As a species that has the same boring physiology, [40:53] but uses it in ways that are unrecognizable. [40:56] As a species that does some things that are simply [40:59] without precedent out there. [41:00] And constantly struggling with what does biology [41:04] have to do with it? [41:05] General structure of the course-- the first half [41:08] of the course is going to be an overview, [41:11] an introduction to the various buckets, [41:14] the various categories. [41:16] And what we're going to go through [41:17] is understanding an introduction to evolutionary theory, [41:22] an introduction to what molecular genetics has [41:26] to do with behavior, behavioral genetics, ethology, [41:30] the brain, endocrinology, each of these buckets. [41:33] And you know what happens next, which [41:35] is in the second half of the course. [41:37] We will look at specific behaviors, and in each case rip [41:41] apart the buckets. [41:42] And in each case, do the strategy [41:44] of what does the behavior look like? [41:46] What happened a second before? [41:48] The world of neurons. [41:50] What happened with the sensory stimuli that trigger [41:52] those neurons, et cetera? [41:54] All the way back to the evolutionary selective [41:56] pressures. [41:57] So the first half of the course is [41:59] going to be the introduction to the buckets. [42:01] And I will tell you right off the bat [42:03] it is a total pain in the rear. [42:04] Because what we're going to be doing [42:06] is like every 2.5 lectures-- just when you were getting [42:09] the vocabulary down-- we're going [42:11] to jump to a completely different bucket. [42:13] It is going to be dizzying, and unpleasant, and all of that. [42:17] And then second half of the course, [42:18] oh, the rewards finally come of then putting all the pieces [42:22] together, looking at individual categories of behavior-- [42:26] sexual behavior, aggressive behavior, parental behavior, [42:31] schizophrenia, depression, personality disorders, language [42:36] use. [42:36] In each of these cases, what's going on a second before? [42:40] What's going on 10 million years before? [42:42] Where do all these buckets disappear in the interactions? [42:47] So that's going to be the strategy for the course. [42:49] Something critical about how the course was designed [42:52] is it's got no prerequisites. [42:55] Because I really think this is a subject that everybody on Earth [42:58] should be forced to learn about it at gunpoint. [43:00] And thus, it's a good thing, I think, [43:03] to have this not be one of those upper level bio classes. [43:06] Let me just get a sense of who's here. [43:07] How many of you are bio types, bio majors, hum bio? [43:12] Psychology? [43:14] Anthro? [43:16] Are there any English Lit grad students in here? [43:19] Yeah. [43:20] OK. [43:23] Good for you. [43:23] Thank you for coming here. [43:26] See what you think in three months. [43:28] But nonetheless, the class has been designed explicitly [43:31] to have no background whatsoever. [43:33] How are we going to do that? [43:35] We're going to do the usual song and dance of weekly sections, [43:38] and reviews, and all that sort of thing. [43:40] But in addition, during this first half [43:43] of the course when we're jumping from category to category, [43:46] we're going to have each week additional sections-- [43:48] a catchup section-- which is for people [43:51] who have no background in that area, [43:53] getting you through the basics, and getting you [43:55] up to speed so that you will be able to then know [43:58] what's up during the lectures. [44:00] So those will be posted. [44:01] The first one of these is-- let me make sure I've got this. [44:05] Yes. [44:05] It will be Thursday at 7:30 in the room next door. [44:10] And this is going to be the introduction [44:12] to evolutionary theory and getting [44:14] you ready for what will be the evolution lectures Wednesday [44:18] and Friday of this week. [44:19] If you don't have a strong background, [44:21] go to these catchup sections. [44:23] The TAs who will be giving that are really [44:26] expert in those areas, lots of background, and this [44:29] will be your chance to catchup. [44:31] Look through the handout. [44:32] I think I have a bunch of terms there [44:34] or something where if you are not terribly [44:36] familiar with those terms in some discipline, that's a sign [44:39] that you should probably go for some of the catchup stuff. [44:42] If you really are just doing this, [44:44] sort of being very adventurous with no background, if you can [44:47] take it pass/fail, that will take off [44:49] a lot of the pressure as well. [44:51] Because you could then actually pay attention to stuff here. [44:53] And the whole point here is to be [44:55] able to do this even if you don't have a science [44:58] background. [44:59] Because the obvious argument I would make [45:01] is everybody has to learn behavioral biology [45:04] because we're being behavioral biologists every time [45:07] we serve on a jury. [45:08] Every time we vote whether or not [45:11] money should be spent on solving some problem, [45:14] whether it's a problem, and whether it's solvable or not. [45:16] Every time we try to make sense of a family [45:19] member sunk in depression. [45:21] Are they having a biochemical disorder, [45:23] or are they just indulging themselves? [45:26] We're behavioral biologists all the time. [45:28] So it's probably a good thing that we be informed ones. [45:31] So the catchup sections there-- take advantage of them. [45:35] What else? [45:36] We will have weekly sections, the usual type. [45:38] People are not assigned to sections. [45:40] There's going to be 18 of them or so a week at various times. [45:44] Go to whichever works for you. [45:46] There will be a midterm in the middle, the midterm coming [45:50] as we finish the last of those categories, last [45:53] of those buckets. [45:54] There will be a final. [45:55] There's no paper or anything like that. [45:58] So that will be the pattern. [45:59] What else? [46:00] Other stuff here. [46:02] Office hours-- my office hours are up on the handout. [46:05] Other things-- breaks. [46:06] We will, with any luck, be able to be [46:10] able to be organized enough so that during each stretch [46:13] of class, there will be a five minute break in the middle [46:15] so you can stand up, and just get [46:17] to the front of the line for the bathroom, [46:19] and then we will resume promptly before you get in there. [46:22] So just to let you clear your heads a bit. [46:24] Assignments, books, reading. [46:26] There are two books that I have assigned for the course. [46:29] One is by me. [46:31] And you don't even have to read it. [46:33] Just go buy a bunch of copies of and bring me the receipt, [46:37] and you've got a great grade in there. [46:39] OK, so that's what is going to be [46:40] pertinent to the second half of the course. [46:43] We're going to give you a list of the chapters that [46:46] make the most sense to read. [46:47] The other book is a book by an author named [46:50] James Gleick called Chaos. [46:52] Chaos, year, after year, after year, in this class [46:55] provokes the strongest opinions. [46:57] A quarter of the people decide it [46:59] is the most irritating, irrelevant thing that [47:01] could possibly have been assigned in the class [47:04] and hate it. [47:05] About half the people never quite [47:06] figure out what's up with it. [47:08] And a quarter of the people, their life is transformed. [47:12] They no longer have to meditate. [47:14] They no longer have to have a-- they are at peace. [47:19] At peace, I tell you. [47:20] Because what this book does is introduce [47:23] this whole radically different way of thinking about biology, [47:27] taking apart a world of reductionism. [47:30] For 500 years, we all have been using a very simple model [47:35] for thinking about living systems. [47:36] Which is, if you want to understand something [47:39] that's complicated, you break it apart into its little pieces. [47:43] And once you understand the little pieces [47:45] and put it back together, you will [47:48] understand the complex thing. [47:50] And what Chaos as an entire field is about-- [47:53] and this was pretty much the first book that [47:55] was meant for the lay public about it-- what Chaos shows [47:58] is that's how you fix clocks. [48:00] That's not how you fix behaviors. [48:02] That's not how you understand behaviors. [48:04] Behavior is not like a clock. [48:07] Behavior is like a cloud. [48:08] And you don't understand rainfall [48:10] by breaking a cloud down into its component pieces [48:13] and gluing them back together. [48:15] So read through that book. [48:16] A lot of it is from physical sciences rather than [48:19] biological, so we'll just be suggesting [48:21] the chapters you should read. [48:22] I will tell you it is the first book [48:25] since Baby Beluga where I've gotten to the last page [48:29] and immediately started reading it over again from the front. [48:32] Because along with Baby Beluga, it's [48:34] had the greatest influence on my life. [48:36] I found this to be the most influential book in my thinking [48:40] about science since college. [48:42] So that is a sign. [48:43] There will also be a bunch of lectures [48:45] in the second half of the course covering these fields of chaos [48:49] and complexity. [48:50] And if you really think about it, [48:52] it is going to force a change in everything else [48:54] that you bring to thinking about this subject. [48:57] In addition, at this moment there is not a reader. [49:01] Because I'm trying to avoid having to get [49:02] you guys to have to buy a reader. [49:04] I'm trying to redo all the assigned readings [49:07] so that will just be from papers that are available online, [49:10] that you'll be able to download. [49:12] I'm about halfway through getting them there. [49:14] With any luck, there will not have to be a reader. [49:16] But if it does exist, it's not going to be big. [49:18] It won't be terribly expensive. [49:20] But there will be a bunch of readings online to download, [49:24] and it will vary. [49:25] In some cases, it will be reading the whole paper. [49:28] In some cases, I'll be suggesting you just [49:31] read the abstract. [49:32] In some cases, it will be to understand what's happening [49:36] in the paper in detail. [49:37] In some cases, this is an example [49:39] of how people in this bucket think about this problem. [49:43] Just read the abstract. [49:44] So all of that will be assigned and made clear. [49:47] What other stuff? [49:48] There's going to be a huge amount of information online. [49:51] The coursework is going to be set up for the class. [49:54] There will be copies of the handouts. [49:57] There will be lecture notes. [49:58] Lecture notes that I have that will be about five to 10 pages [50:02] covering each lecture, which we'll get to about [50:05] the middle of the course. [50:06] And I suspect I will run out of steam by then. [50:09] So they won't occur for the second half. [50:11] There will be commonly asked questions. [50:13] There will be a Q&A. There will be course logistics. [50:16] Some of the slides will be put up in there. [50:19] Make use of that. [50:20] There will be announcements about time changing for office [50:23] hours, and things like that. [50:25] Make sure you make use of that. [50:26] And people who are not formally enrolled, [50:28] we are figuring out a way for you [50:30] to get access to it as well. [50:32] We've also made the decision that after this lecture, [50:35] the handouts will not be on paper. [50:38] And that is because roughly for each lecture, [50:42] we will go through about 5000 pieces of paper, [50:45] even double sided. [50:46] All of this stuff will get posted on Coursework the day [50:49] before. [50:50] And if that's going to make it impossible [50:52] for you to follow what happens in class because you are [50:55] the last human on Stanford who was not living off [50:58] of a computer screen, come and talk to me. [51:00] And we will slip you an actual paper copy of the handouts. [51:04] Most of them, with any luck, we can [51:06] avoid using paper just because of how many people there [51:08] are in here. [51:09] Let's see. [51:10] Other stuff. [51:13] Sections will start this Thursday. [51:16] The regular sections-- all of those will be posted, [51:18] the times for that. [51:20] Office hours won't start until next week. [51:23] The midterm will be in an evening [51:26] rather than during a class time. [51:28] And if we are on schedule, the class time that day [51:30] will be used for review. [51:32] And anything else? [51:33] Oh, a very good suggestion just now given that [51:35] the class before here is humongous, [51:38] and thus we have the impossible problem [51:40] of a lot of people trying to get out [51:42] of that while a lot of people are trying to get into that. [51:44] It might work best for everybody to come in from the top [51:47] so that you flow down the stairs seamlessly [51:50] and drive out those other people before us out the door there. [51:54] That might work a whole lot better. [51:56] Final thing is we have a team of TAs here. [51:59] And they are great. [52:01] Here they are. [52:02] TAs, stand up and be embarrassed. [52:04] OK, stand up, guys. [52:08] There they are. [52:10] There is all but one of them, who is in transit. [52:13] There you are. [52:13] These guys are great. [52:15] They have either taken the course before. [52:17] In some cases they have TA'd the course before. [52:19] They are grad students in various [52:21] of the bucket specialties. [52:23] I would strongly suggest taking advantage of the sections. [52:26] What will evolve after the first few weeks [52:29] is there will be the regular sections going over the course [52:32] material in the usual way. [52:34] There are also being more advanced sections for people [52:37] who have stronger backgrounds. [52:39] Take advantage. [52:40] OK, you guys can sit down. [52:42] Leaving them standing there awkwardly for hours afterward. [52:45] Take advantage of the sections. [52:47] Really greatly skilled TAs. [52:50] OK so that's basically what we got going here. [52:52] Are there any questions? [52:53] [INAUDIBLE] [52:58] Units. [52:59] OK, somebody emailed about units. [53:02] The class is five units, and it's [53:04] because we are meeting for so many hours a week. [53:07] Actually, for a while the class was a six-unit course. [53:10] And that was because of Condoleezza Rice. [53:13] Because when she was the provost here, [53:15] she totally screwed the biology department [53:17] by upping our teaching requirements [53:20] under really nasty conditions. [53:22] So what we all decided was to find ways, [53:25] every single sleazy trick we could [53:27] do to puff up the number of units [53:29] we were supposedly teaching. [53:31] So for a while, the five unit class [53:32] here would get you six units. [53:34] But eventually they caught us, so we stopped doing that. [53:37] So first she did that, and then weapons of mass destruction. [53:41] [LAUGHING] [53:41] So it's a five unit class at the moment. [53:44] Say hi for me if you run into her on campus. [53:47] So five units. [53:50] The workload, I think, will be commensurate with that. [53:53] But it's mainly because of heavy class time. [53:55] One additional thing-- lectures are [53:57] going to be taped and put up online with a day or so [54:01] on Coursework. [54:01] The reason for that is given that this spans two hour [54:04] block, a lot of people have to miss one of the hour blocks. [54:07] And in the past, it has worked to be able to get the stuff up [54:11] online. [54:11] So that will be advantageous for some folks. [54:15] OK. [54:15] Question? [54:16] Yes, there was a question up there. [54:18] [INAUDIBLE] [54:19] OK, you take it back. [54:21] OK, any other questions? [54:24] Bagel guy. [54:25] Did you get your bagel, or did somebody eat it? [54:27] [INAUDIBLE] [54:28] OK, good. [54:30] Good. [54:30] The social contract comes through. [54:32] Yeah? [54:32] [INAUDIBLE] [54:34] What's that? [54:35] [INAUDIBLE] [54:38] Yes. [54:40] I don't remember. [54:41] [LAUGHTER] [54:43] May 3rd. [54:43] May 3rd for the midterm. [54:46] 7:30 in the evening. [54:48] It is a Monday. [54:51] June 4th for the final. [54:56] OK, more questions? [54:57] Yeah? [54:57] [INAUDIBLE] [54:59] What's the format of the midterm and the final? [55:02] In an ideal world, given the whole emphasis [55:05] here on no buckets, blah blah, et cetera, [55:08] It would be long essays, and requirements of sonnets, [55:11] and sensitive haikus about the hypothalamus. [55:14] But simply because of numbers in here, [55:16] we are reduced to sort of like the lowest common denominator, [55:20] a lot of multiple choice questions, [55:22] just to make things saner for the TAs. [55:24] Because it is an unbelievable job [55:26] to try to grade this many papers that quickly. [55:29] Broadly, intellectually, what the midterm [55:31] is going to be about is just touching base, [55:34] making sure you understand the basics of each [55:37] of those buckets, each of those disciplines. [55:39] A little bit of forcing you to think across disciplines. [55:42] What the final is going to be entirely about [55:45] is forcing you to think across the disciplines, [55:48] across the buckets there. [55:49] So it's going to be some very different intellectual foci [55:52] in there. [55:52] Midterm-- have the facts down. [55:54] Hopefully it won't be quite as mindless as that, [55:56] but that's the main function of the midterm. [55:58] OK, more questions? [55:59] [INAUDIBLE] [56:10] OK. [56:10] TAs, did you guys decide to videotape the catchup section? [56:13] [INAUDIBLE] [56:15] Audio, OK. [56:16] [INAUDIBLE] [56:19] OK. [56:19] Other office hours, or it's going to be taped and put up [56:23] online on Coursework. [56:24] And if there's critical handouts, visuals, [56:27] those will be posted there as well. [56:29] Good. [56:30] More questions? [56:30] [INAUDIBLE] [56:35] Yes. [56:36] And it's going to be for each. [56:38] It's going to be in advance of the next three lectures. [56:40] [INAUDIBLE] [56:45] Final is at 7:30 for two hours. [56:47] [INAUDIBLE] [56:48] The final? [56:49] Oh, the final, the final. [56:50] 5:15. [56:51] [INAUDIBLE] [56:54] 12:15. [56:54] [LAUGHTER] [57:01] Just to get that up there. [57:02] 12:15. [57:03] More questions? [57:10] For more, please visit us at standord.edu.