Food Brands Flout Grice's Maxims to Mislead Shoppers, Scott Says

Tom Scott

Marketers exploit Grice's Cooperative Principle by highlighting obvious attributes on food labels, deliberately flouting conversational maxims to imply rival products carry defects without legally lying.

AI-assisted summary of The Hidden Rules of Conversation — original source. Check the original for full context.

Source published: 2020-05-04

Key ideas

Everyday human conversation relies on the Cooperative Principle and Grice's Maxims to convey vast unspoken context without requiring hyper-logical, unambiguous speech. (0:00)
The four descriptive Gricean maxims—Quantity, Quality, Relation, and Manner—guide how listeners interpret statements and connect them to context. (0:47)
Breaking a maxim can occur via violation (deception/lying) or flouting (openly breaking a rule to generate conversational implicature). (3:34)
Marketers frequently flout Gricean maxims with redundant claims like 'vegan tomatoes' or 'asbestos-free cereal' to falsely imply competing products lack those qualities. (4:26)

Detailed notes

## Background Published on YouTube by Tom Scott on May 4, 2020, this video introduces Paul Grice's conversational maxims, explaining the subtle guidelines people subconsciously follow to understand everyday language. Co-written with Molly Ruhl and linguist Gretchen McCulloch, the video examines the Cooperating Principle and why technically accurate packaging like 'asbestos-free cereal' or 'vegan tomatoes' feels inherently suspicious.

## TL;DR Tom Scott breaks down language philosopher Paul Grice's 1975 Cooperative Principle, which asserts that everyday conversation works because people operate under shared communicative assumptions. Rather than relying on hyper-literal speech, participants intuitively use four core maxims—Quantity, Quality, Relation, and Manner—to infer massive amounts of contextual meaning from brief exchanges. The video contrasts deceptive violations of these maxims with 'flouting,' where speakers openly break a guideline to trigger conversational implicature. This phenomenon explains both subtle real-world signals, like understated recommendation letters, and manipulative product marketing claims.

## Atmosphere & style The video carries a brisk, engaging, and intellectually curious tone characteristic of Tom Scott's educational pieces. Scott combines accessible thought experiments with dry, witty observations about academic philosophy and grocery packaging. The pacing is crisp and conversational, turning formal linguistic theory into a series of intuitive, humorous 'aha!' moments that make viewers reexamine the hidden mechanics of their own daily dialogue.

## Bulletin - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) Everyday human conversation relies on the Cooperative Principle and Grice's Maxims to convey vast unspoken context without requiring hyper-logical, unambiguous speech. - [00:47](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=47s) The four descriptive Gricean maxims—Quantity, Quality, Relation, and Manner—guide how listeners interpret statements and connect them to context. - [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) Breaking a maxim can occur via violation (deception/lying) or flouting (openly breaking a rule to generate conversational implicature). - [04:26](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=266s) Marketers frequently flout Gricean maxims with redundant claims like 'vegan tomatoes' or 'asbestos-free cereal' to falsely imply competing products lack those qualities.

## Key takeaways - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) Labels like 'vegan tomatoes' or 'asbestos-free cereal' feel suspicious because they present redundant information contrary to normal conversational expectations. - [00:22](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=22s) Language philosopher Paul Grice formulated Grice's Maxims in his 1975 paper 'Logic and Conversation' to bridge literal logic and everyday communication. - [00:38](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=38s) The Cooperative Principle assumes both conversational participants share a baseline presumption of mutual cooperation. - [00:53](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=53s) The Maxim of Quantity requires providing as much information as needed to be understood, but no more. - [01:03](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=63s) The Maxim of Quality dictates telling the truth. - [01:06](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=66s) The Maxim of Relation instructs speakers to be relevant, prompting listeners to actively infer connections between statements. - [01:12](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=72s) The Maxim of Manner requires clear, straightforward delivery, which Grice's own dense philosophical prose ironically struggled to meet. - [02:12](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=132s) A brief exchange like 'I'm out of petrol' and 'There's a garage down the road' conveys an entire solution through implicature without explicit exposition. - [03:44](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=224s) Violating a maxim involves dishonesty, deception, or outright lying to a conversational partner. - [03:49](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=229s) Flouting a maxim occurs openly and conspicuously so the listener notices the omission and infers an unspoken meaning. - [03:57](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=237s) An academic recommendation letter praising only handwriting or attendance deliberately flouts Quantity to signal a student's lack of competence. - [04:26](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=266s) Product packaging exploits conversational implicature to manipulate consumer perception without technically uttering a legal falsehood.

## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) The Cooperative Principle and Grice's Maxims

Seeing a package of "vegan burgers" on a supermarket shelf makes complete sense, but spotting a label that proclaims "vegan tomatoes" immediately triggers suspicion. It mirrors the classic joke about "asbestos-free cereal": while technically accurate, advertising the fact feels unsettlingly out of place. Tom Scott explains that such labels feel off because they run counter to Grice's Maxims, a collection of communication guidelines first outlined by language philosopher Paul Grice in his 1975 paper *Logic and Conversation*. Grice sought to address the vast gulf between literal logical formalism and everyday natural speech, recognizing that people regularly communicate far more meaning than the bare dictionary definitions of their words.

To make this possible without requiring humanity to invent a hyper-logical, completely unambiguous language, conversations rely on what Grice dubbed the Cooperative Principle: the baseline presumption that both participants are cooperating with one another. People instinctively try to anchor whatever someone says into the surrounding context and whatever has already occurred. This dynamic is obvious when it breaks down, such as in video games when a non-player character recites identical canned dialogue regardless of whether the player just saved their village or burned their house to the ground. In real life, humans assume their conversational partners are adhering to four core guidelines, which are descriptive rather than prescriptive:

- **Maxim of Quantity:** Provide as much information as required to be understood, and no more. (Labeling tomatoes as "vegan" violates this, because tomatoes are already universally understood to be vegan.) - **Maxim of Quality:** Tell the truth. - **Maxim of Relation:** Be relevant. Listeners automatically assume what you say connects to what was just discussed and will search for that connection. - **Maxim of Manner:** Be clear in delivery.

Tom observes with some amusement that Grice's own philosophical prose was so dense and repeatedly restated that it barely adhered to his own Maxim of Manner. As Tom Scott points out regarding human communication: “Grice wrote that for that to be possible without having some hyper-logical unambiguous language, we must be operating under some shared assumptions, what he called the Cooperative Principle.”

[02:12](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=132s) Context and Implication: The Stranded Driver

To demonstrate how the maxims function seamlessly in everyday life, Tom presents a two-line exchange: one person says, “I’m out of petrol,” and Tom replies, “There’s a garage down the road.” Analyzed purely through strict, literal logic, these are two completely disconnected factual assertions. Yet, because humans automatically apply the Cooperative Principle, an extensive web of unspoken meaning is instantly deduced without needing explicit exposition.

Every maxim performs heavy lifting to make the short exchange intelligible: - **Relation:** The listener deduces that the mentioned garage almost certainly sells petrol, because otherwise mentioning it would be pointless. - **Quantity:** Tom says just enough to convey the practical takeaway: push the vehicle there, buy fuel, and resolve the roadside emergency. - **Quality:** The stranded motorist can safely assume Tom is telling the truth rather than inventing a location or guessing. - **Manner:** Even an American unaccustomed to British vocabulary can infer from context that "garage" refers to a commercial petrol filling station rather than a private residential garage where an ordinary homeowner parks their car.

As Tom Scott notes when reviewing the interaction, “All that backstory about a stranded car was implied just by the words ‘I’m out of petrol’.”

```mermaid flowchart TD accTitle: Cooperative Principle Mechanics in Conversation accDescr: Flowchart showing how the statement "There's a garage down the road" is interpreted through the four Gricean Maxims.

A["Statement: 'I'm out of petrol'"] --> B["Response: 'There's a garage down the road'"]

subgraph G["Gricean Maxims at Work"] B --> C["Relation: Garage sells fuel"] B --> D["Quantity: Push car, buy fuel, resolve dilemma"] B --> E["Quality: Information is truthful and reliable"] B --> F["Manner: 'Garage' means a commercial gas station"] end

G --> H["Understood: Full solution without explicit exposition"] ```

[03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) Conversational Implicature, Flouting, and Marketing Tricks

When speakers choose not to follow the maxims, they invite what Grice termed "Conversational Implicature"—deliberately implying meaning that remains unsaid. Tom explains that there are two distinct ways to break a maxim: violating it and flouting it. Violating a maxim involves dishonesty, deception, or outright lying. Flouting, by contrast, occurs when a speaker breaks a maxim openly and conspicuously, intending for the listener to notice the omission and interpret the hidden message beneath it.

To illustrate flouting, Tom cites Grice's classic example of an academic tasked with writing a letter of recommendation for a graduate school applicant in whom they have zero confidence. Tom quips that he suspects this was simply Grice grumbling about a real-life student. The professor writes: *"The student’s command of English is excellent, and his attendance at tutorials has been regular."* While factually positive, it blatantly flouts the Maxim of Quantity by withholding any assessment of the student's actual philosophical ability, effectively signaling to the admissions board that the candidate is unsuitable.

This same communicative trick frequently appears in modern product marketing. Labels boasting that food is "vegan," "asbestos-free," "low in fat," or "low in sugar" flout the maxims to manipulate customer perception. As Tom Scott summarizes, “They’re flouting Grice’s maxims to imply that the other brands aren’t, or to imply that those claims are good things to be.” While such advertising is not legally considered lying, it violates the spirit of the Cooperative Principle—unless, Tom jokes, there really is an evil, animal-byproduct tomato circulating on the market. In closing, Tom credits co-writers Molly Ruhl and Gretchen McCulloch, noting that Gretchen's linguistics podcast *Lingthusiasm* explores these language phenomena in greater depth.

## Mentioned Tom Scott, Paul Grice, Molly Ruhl, Gretchen McCulloch, Logic and Conversation, Lingthusiasm, Because Internet, Willow Marler, Graham Haerther

## Video description Gricean Maxims are a vital part of how we understand each other: a set of... well, maybe "rules" is a bit strong. They're guidelines that we follow without realising it. And it's the reason that "asbestos-free cereal" sounds suspicious.

Written with Molly Ruhl and Gretchen McCulloch. Gretchen's podcast Lingthusiasm is at http://lingthusiasm.com/

Gretchen's book BECAUSE INTERNET, all about the evolution of internet language, is available: 🇺🇸 US: https://amzn.to/30tLpjT 🇨🇦 CA: https://amzn.to/2JsTYWH 🇬🇧 UK: https://amzn.to/31K8eRD

(Those are affiliate links that give a commission to me or Gretchen, depending on country!)

Graphics by Willow Marler: https://wmad.co.uk Audio mix by Graham Haerther: https://haerther.net

REFERENCES: Munroe, R. (2009). "Free". https://xkcd.com/641/ Grice, H.P. (1975). "Logic and Conversation," Syntax and Semantics, vol.3 edited by P. Cole and J. Morgan, Academic Press. Reprinted as ch.2 of Grice 1989, 22–40.

🟥 MORE FROM TOM: https://www.tomscott.com/ (you can find contact details and social links there too) ❓ LATERAL, free weekly podcast: https://lateralcast.com/ https://youtube.com/lateralcast/ 👥 THE TECHNICAL DIFFICULTIES: https://youtube.com/techdif

[Source](https://www.youtube.com/watch?v=IJEaMtNN_dM)

中文简报

斯科特：食品品牌违背格赖斯准则误导消费者营销人员利用格赖斯的合作原则，在食品标签上标榜显而易见的属性，故意违背会话准则，在不构成法律意义上说谎的情况下暗示竞争对手的产品存在缺陷。汤姆·斯科特（Tom Scott）详细解析了语言哲学家保罗·格赖斯（Paul Grice）于1975年提出的合作原则，该原则认为日常对话之所以能够进行，是因为人们在共同的交际假设下展开交流。参与者无需依赖极度字面化的言语，而是凭直觉运用数量、质量、关联和方式这四项核心准则，从简短的交流中推断出大量的语境含义。视频对比了对这些准则的欺骗性“违反”与“公然违背”（flouting），后者指说话者公开打破某项准则以触发会话含意。这种现象既解释了现实生活中微妙的信号传递（例如措辞含蓄的推荐信），也解释了操纵性的产品营销说辞。人类的日常对话依赖于合作原则和格赖斯准则来传递大量未明说的语境信息，而无需极度合乎逻辑、毫无歧义的言语。 (0:00) 格赖斯的四条描述性准则——数量、质量、关联和方式——引导听者如何理解话语并将其与语境联系起来。 (0:47) 打破准则可以通过“违反”（欺骗/说谎）或“公然违背”（公开打破规则以产生会话含意）来实现。 (3:34) 营销人员经常通过诸如“纯素番茄”或“不含石棉的麦片”等冗余声称来公然违背格赖斯准则，从而错误地暗示竞品不具备这些特性。 (4:26)

Reading summary

Paul Grice's Cooperative Principle and conversational maxims describe how human communication conveys far more meaning than literal definitions through shared, unspoken assumptions. Tom Scott explains that listeners continuously infer intent from context, and that speakers can exploit or openly break these descriptive guidelines in everyday dialogue and modern marketing. Shared Assumptions and the Four Maxims (0:00) In his 1975 paper Logic and Conversation, language philosopher Paul Grice examined the divide between strict logical formalism and natural speech. To explain how people exchange nuanced meaning without needing a hyper-logical, unambiguous language, Grice proposed the Cooperative Principle: the baseline presumption that conversation partners are cooperating with one another. Listeners instinctively anchor statements to the surrounding context, and conversations break down when this presumption fails, such as when video game non-player characters repeat canned lines regardless of the player's prior actions. According to Grice, communication relies on four descriptive guidelines rather than prescriptive rules: the Maxim of Quantity (providing just the necessary amount of information), the Maxim of Quality (truthfulness), the Maxim of Relation (relevance to the topic at hand), and the Maxim of Manner (clarity of delivery). Scott observes that while Grice articulated these principles to clarify human communication, Grice's own dense philosophical prose barely adhered to his Maxim of Manner. Inferring Meaning in Everyday Exchanges (2:12) The Cooperative Principle allows speakers to communicate broad contextual narratives with minimal phrasing. Scott demonstrates this through a roadside interaction where one person announces, "I'm out of petrol," and another replies, "There's a garage down the road." Viewed strictly as isolated logical assertions, the two statements share no formal link. However, applying Grice's maxims instantly resolves the exchange without explicit exposition. Listeners rely on Relation to deduce that the mentioned garage sells fuel, as offering the location would otherwise be irrelevant. Quantity supplies just enough actionable information to resolve the emergency, while Quality allows the stranded driver to trust the accuracy of the statement. Finally, Manner leads the listener—even an American unfamiliar with British terminology—to infer from context that "garage" refers to a commercial filling station rather than a private residential parking structure. Flouting Maxims in Recommendations and Advertising (3:34) When speakers deliberately step outside these communication guidelines, they create what Grice termed conversational implicature—conveying meaning that remains unsaid. Scott distinguishes between violating a maxim, which involves lying or deceit, and flouting a maxim, where a speaker breaks a rule conspicuously so that the listener actively looks for a hidden message. As an illustration, Scott cites Grice's example of a philosophy professor writing a recommendation letter that only praises an applicant's English skills and regular tutorial attendance; by omitting any assessment of philosophical talent, the writer flouts Quantity to signal the candidate's inadequacy. Modern marketing frequently relies on this exact communicative maneuver. Food labels highlighting that products are "vegan," "low in fat," or "asbestos-free" flout the Maxim of Quantity by prominently declaring traits that are already inherent or expected, such as in the case of tomatoes. Scott notes that while such labels do not constitute legal falsehoods, they flout conversational conventions to manipulate perception, implying that rival brands lack those positive qualities or that the highlighted traits carry special merit. While Grice's maxims illustrate how everyday speech functions cooperatively without hyper-logical precision, Scott highlights that deliberately flouting these conventions enables commercial advertisers and conversationalists to steer listener perceptions and imply unsubstantiated claims without uttering literal falsehoods.

精炼阅读摘要

Tom Scott基于语言哲学家保罗·格莱斯（Paul Grice）的理论阐述了人类日常交流背后的“合作原则”与对话准则，解释了人们如何在字面逻辑之外凭借默契和语境推导未明说的含义，并指出了商业营销如何通过刻意违背准则来制造心理暗示。合作原则与四大对话准则的建立基石 (0:00) 在超市货架上看到“纯素汉堡”合情合理，但看到标有“纯素西红柿”或“不含石棉的麦片”却会令人感到突兀与怀疑。Tom Scott指出，这种违和感源于对语言哲学家保罗·格莱斯（Paul Grice）在1975年论文《逻辑与对话》（Logic and Conversation）中提出的对话准则的破坏。格莱斯旨在解决形式逻辑的字面定义与人类自然语言之间的巨大鸿沟，指出人们在日常交流中传达的信息往往远超出词汇的字面含义。人类无需发明一种毫无歧义的超逻辑语言，正是因为日常交流建立在“合作原则”（Cooperative Principle）的基准假设之上，即对话双方默认彼此正在通力合作，并会自动将对方的话语与现实语境相锚定。相比之下，电子游戏中非玩家角色（NPC）无论玩家拯救村庄还是烧毁房屋都只会重复机械台词的现象，恰恰展示了合作原则缺席时的沟通断裂。在格莱斯的体系中，合作原则由四条描述性（而非规范性）的核心准则构成：数量准则（提供恰到好处的信息量，不多也不少；西红柿本身就是纯素的，添加该标签便违背了此准则）、质量准则（陈述真实信息）、关联准则（保持相关性，听者会自动寻找与前文的联系）以及方式准则（表达清晰明了）。Scott戏谑地提到，格莱斯本人的学术论著行文极其晦涩且频繁重复，实际上几乎未遵守他自己设定的方式准则。语境推论：从字面逻辑空白推导完整意图 (2:12) 为了证明格莱斯准则在日常生活中的无缝运转，Scott以一段极为简短的对话为例：一人表示“我的车没油了（I’m out of petrol）”，Scott回答“前边路旁有一家维修加油站（There’s a garage down the road）”。若仅从严格的形式逻辑分析，这是两句毫无事实因果关联的陈述；但基于人类本能应用的合作原则，听者无需额外的冗长说明即可瞬间推导出一整套复杂的未明言背景与行动方案。在这段互动中，四条准则均发挥了关键的推论作用：关联准则让听者认定该地点必定销售汽油，否则提及它便毫无意义；数量准则保证了回答仅包含解决推车、购油和脱困所需的实用信息，没有多余赘述；质量准则使求助者能够确信该信息真实可靠，并非随口编造；方式准则使得即便是对英式英语词汇不熟的外国听众，也能根据语境准确理解“garage”是指商业加油服务站而非私人家用车库。这种日常推导证明了人类语言具备极高的信息压缩与解码效率。蔑视准则与言外之意的商业营销操纵 (3:34) 当说话者选择不遵守准则时，便会产生格莱斯所谓的“会话含义”（Conversational Implicature），即通过故意不说某些话来传递弦外之音。Scott区分了打破准则的两种形式：其一是“违反”（violating），涉及撒谎、欺骗或刻意隐瞒；其二是“蔑视”（flouting），即公开且显著地打破准则，意在让听者察觉这种异样并解读出其深层暗含的意图。格莱斯曾举过一个经典案例：一位对学生能力毫无信心的哲学教授在写研究生推荐信时仅写道“该学生的英语水平极佳，且出勤十分规律”，这种在关键学术评价上的刻意沉默公然蔑视了数量准则，从而委婉却明确地向招生委员会传递了该学生不适合从事哲学研究的信号。 Scott进一步指出，现代消费品营销频繁利用这种“蔑视准则”的手法操纵公众认知。诸如强调产品“纯素”、“不含石棉”、“低脂”或“低糖”的包装标签，在逻辑上往往属于显而易见的废话，但商家正是通过故意强调这些不必要的信息，暗示竞争对手的产品可能存在缺陷，或者暗示该项属性属于难能可贵的优点。这类宣传在法律层面或许并不构成虚假陈述，但本质上违背了合作原则的沟通诚意。人类日常交流极大地依赖于未明言的合作假定与语境推断，理解格莱斯准则不仅揭示了语言沟通的高效机制，也解释了商业广告如何利用暗示手法规避法律责任并操纵消费者认知。该节目由Tom Scott与语言学播客Lingthusiasm的主持人Gretchen McCulloch及Molly Ruhl共同编撰。

Detailed notes — zh

## Background 该视频由科普创作者 Tom Scott 于 2020 年 5 月 4 日发布在 YouTube 平台。根据视频简介，内容主要探讨了格莱斯准则（Gricean Maxims）这一套人们在潜意识中共同遵循的交际准则，并以此解释为何“不含石棉的麦片”这类宣传标语听起来格外可疑。本期脚本由 Tom Scott 携手 Molly Ruhl 及语言学家 Gretchen McCulloch 联合撰写。 ## TL;DR 视频深入浅出地介绍了语言哲学家保罗·格莱斯提出的“合作原则”及其四大准则（数量、质量、关系与方式准则），解释人类如何在无需绝对严密逻辑语言的情况下高效交流。通过日常对话案例（如“我没油了”与“路边有一家加油站”），Tom 展示了人们如何默认彼此合作并自动推导出丰富的隐性语境。当人们故意“蔑视”准则时，便会产生富有潜台词的“会话含义”，正如哲学教授用只夸出勤率的推荐信委婉表达对学生的否定。最后，视频指出商业营销常利用这一交际心理，通过标注“纯素西红柿”或“低脂”等冗余标签来恶意暗示竞品有问题，从而在不撒谎的前提下操纵消费者的认知。 ## Atmosphere & style 视频延续了 Tom Scott 标志性明快利落、风趣幽默且逻辑清晰的科普风格。从游戏 NPC 的机械化对话到现实中的荒诞商品标签，主讲人以极具表现力的叙述将枯燥的语言哲学拆解得生动形象。整体观感轻松流畅而又发人深省，让观众在莞尔一笑的同时，敏锐觉察到日常言语背后隐藏的思维暗流与心理博弈。 ## Bulletin - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 保罗·格莱斯（Paul Grice）在 1975 年提出合作原则（Cooperative Principle），指出人类日常交流之所以能省略繁琐细节，是因为双方默认彼此基于数量、质量、关系与方式四大准则通力协作。 - [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) 公然蔑视（Flouting）交际准则会产生“会话含义”（Conversational Implicature），交流者常利用这种言外之意来隐晦表达批评或额外潜台词。 - [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) 商业营销经常利用对准则的故意违背，通过标记“不含石棉的麦片”或“纯素西红柿”等冗余标签，诱使消费者产生竞争对手可能存在缺陷的心理暗示。 ## Key takeaways - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 格莱斯准则（Grice's Maxims）是一套人们在交流中不自觉遵守的引导性准则，而非强制性交际法规。 - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 格莱斯的合作原则旨在弥合自然语言丰富含义与纯粹逻辑形式主义之间的鸿沟，避免日常交流需要极度严密的无歧义逻辑语言。 - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 人类倾向于本能地将听到的对话拟合进现实语境中，电子游戏 NPC 脱离情境的重复对话会打破这种合理拟合感。 - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 数量准则（Maxim of Quantity）要求提供恰到好处的信息量，多余的信息容易引起不必要的疑虑。 - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 质量准则（Maxim of Quality）要求陈述真实信息，说话者需说真话且提供有根据的事实。 - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 关系准则（Maxim of Relation）强调所言内容必须与当前谈话背景高度相关，倾听者会自动在上下文中寻找内在关联。 - [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 方式准则（Maxim of Manner）要求表达简明清晰，尽管格莱斯本人在阐述该理论时用词相当冗长复杂。 - [02:12](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=132s) 通过“我没油了”与“前方有家修车厂/加油站”的互动，展示了人类仅凭寥寥数语便可借助四大准则自动补全大量上下文信息。 - [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) 打破准则的方式主要分为两类：旨在欺骗的“违反”（Violating）与公开期望对方识破潜台词的“蔑视”（Flouting）。 - [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) 推荐信仅夸赞学生“英语极佳且出勤规律”是蔑视数量准则的典型例子，以此公然传达该生学术造诣不足的弦外之音。 - [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) 营销中诸如“低脂”、“低糖”或“纯素西红柿”的宣传技巧并未直接撒谎，而是通过蔑视合作原则诱导消费者进行负面联想。 ## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=0s) 合作原则与格莱斯的四大准则在超市货架上看到“纯素汉堡”（vegan burgers）是合情合理的，但如果货架上摆着“纯素西红柿”（vegan tomatoes），就会显得格外可疑。这就像那个关于“不含石棉的麦片”（asbestos-free cereal）的经典老笑话一样。这类标签违背了语言哲学家保罗·格莱斯（Paul Grice）提出的一组沟通准则——格莱斯准则（Grice's Maxims）。格莱斯在 1975 年发表了论文《逻辑与对话》（*Logic and Conversation*），试图解决自然语言与所谓“逻辑形式主义”（logical formalism）之间的鸿沟。人类在交流时，传递的信息远远超过字面本身的意思；为了在不需要某种超级严密、绝无歧义的逻辑语言的前提下实现这一点，交流双方必须遵循一套共同的假设，格莱斯将其称为“合作原则”（Cooperative Principle）。合作原则的核心在于：我们在交谈时默认彼此是在通力合作的。人类总是本能地尝试将对方所说的话套入当前的现实情境或之前的谈话背景中。正因如此，在玩电脑游戏时，如果某个 NPC 无论是在玩家拯救了他们的村庄还是烧毁了他们的房屋后，都说着一模一样的话，我们立刻就能察觉对方是预先编写好程序的，因为我们无法将他们的话语与当下的具体情境合理拟合。日常对话中，除非身处电子游戏里，否则我们默认交谈对象都在遵守这些准则。格莱斯准则并不是强制性的规范，而是一套引导性的准则（guidelines），具体包括四大准则： - **数量准则（Maxim of Quantity）**：提供所需的信息量即可，切勿提供过量信息。正如“纯素西红柿”的例子，“西红柿”一词本身就说明它是纯素的，提供过多信息反而让人心生疑窦。 - **质量准则（Maxim of Quality）**：说真话，提供真实的信息。 - **关系准则（Maxim of Relation）**：保持相关性。倾听者会默认你说的话与刚刚的谈话存在某种联系，并主动去寻找这种关联。 - **方式准则（Maxim of Manner）**：表达要清晰明白。格莱斯当年表述该准则时用词冗长，甚至自己就没太遵守这条准则，毕竟哲学家往往喜欢长篇大论。正如 Tom Scott 所言：“Grice wrote that for that to be possible without having some hyper-logical unambiguous language, we must be operating under some shared assumptions, what he called the Cooperative Principle.” ```mermaid flowchart TD accTitle: 格莱斯合作原则与四大准则 accDescr: 展示合作原则下分出的四大交际准则：数量、质量、关系和方式。 CP["合作原则 (Cooperative Principle)"] CP --> QN["数量准则 (Maxim of Quantity) 信息恰到好处"] CP --> QL["质量准则 (Maxim of Quality) 说真话"] CP --> RL["关系准则 (Maxim of Relation) 保持相关性"] CP --> MN["方式准则 (Maxim of Manner) 清晰明了"] ``` --- ### [02:12](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=132s) 对话实战：汽油与加油站的隐性信息传递通过一个正面案例可以清楚看合格莱斯准则如何在日常对话中发挥作用。假设甲说了一句：“我没汽油了（I’m out of petrol）”，乙回答道：“顺着路往前走有一家修车厂/加油站（there’s a garage down the road）”。如果不考虑语境，单看字面极其死板的逻辑意义，这两句话之间完全没有任何必然联系，仅仅是两个陈述事实的独立句子。但在默认乙遵守合作原则的前提下，甲能自动推导出一整套连贯的信息： - 根据**关系准则**，乙提到的这家 garage 里面大概率有汽油可卖。 - 根据**数量准则**，乙无需多言，仅仅这一句话就足以暗示：甲可以把车推到那里去买油，进而彻底解决“车辆抛锚滞留”的危机（事实上，“车抛锚了”这层前情提要本身也是甲仅凭一句“我没汽油了”通过合作原则暗示出来的）。 - 根据**质量准则**，甲可以信任乙说的是真话，而不是瞎编或猜测。 - 根据**方式准则**，即便对方对英国方言不太熟悉，也能理解这里的“garage”指的是美式英语中的“加油站”（gas station），而不是某人私宅用来停放车辆的私人车库。 Tom Scott 对此总结道：“All that got implied from just the phrase ‘there’s a garage down the road’.” 仅仅依靠几个词，人类凭借合作原则就能省去无数繁琐的背景交代，高效达成理解。 --- ### [03:34](https://www.youtube.com/watch?v=IJEaMtNN_dM&t=214s) 违背准则与“蔑视准则”：会话含义与营销心机当人们不遵守这些准则时，情况就变得微妙起来。格莱斯指出，当有人故意打破准则时，其实是在寻求产生“会话含义”（Conversational Implicature），即通过弦外之音来暗示那些没有明说的内容。打破准则的方式主要有两种：一种是“违反”（violating），比如直接撒谎骗人；另一种则是“蔑视 / 故意违反”（flouting），即以一种明显期望对方能够察觉的方式去打破准则。格莱斯曾给过一个经典范例：一位哲学系教授不得不为一名自己完全不看好的学生写研究生推荐信。正如 Tom Scott 调侃的那样，这很可能是格莱斯本人在悄悄抱怨自己的某个学生。这位教授在推荐信中写道：“该生的英语能力极佳，且出勤十分规律（The student’s command of English is excellent, and his attendance at tutorials has been regular）。” 从字面来看，这确实是一封推荐信，但它严重违背了**数量准则**——提供的信息量实在太少了，对该学生的哲学学术造诣只字未提。写信人正是通过公然蔑视数量准则，期望看信的招生委员会心领神会，读懂其真正的潜台词：这个学生在专业上根本不行。同样的心理机制也被商业营销玩得炉火纯青。商品包装上标注“纯素西红柿”、“不含石棉的麦片”，或者现实中常见的“低脂”（low in fat）或“低糖”（low in sugar），本质上都是在蔑视格莱斯准则。品牌商通过强调这些常识性或多余的信息，恶意暗示竞争对手的品牌可能含有石棉、动物成分，或者暗示带有这些标签的食品本身更健康优质。这种做法在技术上并不算撒谎，但正如 Tom Scott 所评价的：“It’s just not playing fair by the Cooperative Principle.” 他们只是没有按照合作原则公平出牌，利用了人类本能寻找潜台词的交流习惯。 - **脚本与致谢合作者**：本期视频脚本由 Tom Scott 与 Molly Ruhl 以及 Gretchen McCulloch 共同撰写（Gretchen 主持语言学播客 *Lingthusiasm*）。 ## Mentioned 保罗·格莱斯 (Paul Grice), Tom Scott, Molly Ruhl, Gretchen McCulloch, Willow Marler, Graham Haerther, Randall Munroe, 《逻辑与对话》(Logic and Conversation), 《Because Internet》, Lingthusiasm, Lateral, The Technical Difficulties, xkcd ## Video description Gricean Maxims are a vital part of how we understand each other: a set of... well, maybe "rules" is a bit strong. They're guidelines that we follow without realising it. And it's the reason that "asbestos-free cereal" sounds suspicious. Written with Molly Ruhl and Gretchen McCulloch. Gretchen's podcast Lingthusiasm is at http://lingthusiasm.com/ Gretchen's book BECAUSE INTERNET, all about the evolution of internet language, is available: 🇺🇸 US: https://amzn.to/30tLpjT 🇨🇦 CA: https://amzn.to/2JsTYWH 🇬🇧 UK: https://amzn.to/31K8eRD (Those are affiliate links that give a commission to me or Gretchen, depending on country!) Graphics by Willow Marler: https://wmad.co.uk Audio mix by Graham Haerther: https://haerther.net REFERENCES: Munroe, R. (2009). "Free". https://xkcd.com/641/ Grice, H.P. (1975). "Logic and Conversation," Syntax and Semantics, vol.3 edited by P. Cole and J. Morgan, Academic Press. Reprinted as ch.2 of Grice 1989, 22–40. 🟥 MORE FROM TOM: https://www.tomscott.com/ (you can find contact details and social links there too) ❓ LATERAL, free weekly podcast: https://lateralcast.com/ https://youtube.com/lateralcast/ 👥 THE TECHNICAL DIFFICULTIES: https://youtube.com/techdif [Source](https://www.youtube.com/watch?v=IJEaMtNN_dM)

Original transcript

[0:00] “Vegan burgers” are a sensible thing to find on a supermarket shelf. [0:03] But “vegan tomatoes” wouldn’t be. [0:05] In fact, those tomatoes would sound a bit suspicious: [0:08] it’s the same as the old joke about asbestos-free cereal. [0:11] Those labels are ignoring one of Grice’s Maxims, [0:14] a set of… guidelines that explain how we communicate with each other. [0:18] Paul Grice was a philosopher of language, [0:20] and in '75 he published a paper called "Logic and Conversation". [0:24] He was dealing with the gap between natural language and what’s called “logical formalism”. [0:29] Basically, we communicate far more than just the literal meaning of our words. [0:34] Grice wrote that for that to be possible without having some hyper-logical unambiguous language, [0:39] we must be operating under some shared assumptions, [0:42] what he called the Cooperative Principle. [0:45] We assume that we are cooperating with each other when we are talking. [0:49] Which is obvious, right? [0:50] But there's a deeper point there: [0:52] we all try to fit what other people say [0:55] into the context of what’s happening or what’s already been said. [0:58] That's part of why, [0:59] when we play a computer game and a character says exactly the same thing [1:03] no matter if we’ve just saved their village or burned down their house, [1:07] we can tell that they're preprogrammed. [1:09] We can't find a way to fit their words to the situation. [1:12] So here are Grice’s Maxims, and if you’re not in a video game, [1:15] these are the rules that we assume our conversation partners are following. [1:19] Although, despite how they’re written, [1:21] they are not prescriptive, you-must-do-this rules: they’re just guidelines. [1:27] So first: the Maxim of Quantity: give as much information as required, and no more. [1:33] Which is what we're talking about with vegan tomatoes. [1:35] We already know they’re vegan from the word “tomato”, [1:38] giving too much information is strange. [1:41] Next, the Maxim of Quality: tell the truth. [1:45] Next, there’s the Maxim of Relation: be relevant. [1:48] The person you’re talking to will assume that what you’re saying [1:50] is related to what they just said in some way, [1:54] and they’ll try to find what that connection is. [1:56] And finally, the Maxim of Manner: [1:59] be clear in what you’re saying. [2:01] Although Grice phrased that in a way that I don’t think actually follows his own guidelines? [2:05] Actually, all of these maxims were stated and restated at length. [2:09] But then, he was a philosopher. They tend to do that. [2:12] So let’s have a good example of using Grice’s Maxims, [2:15] and after that, a deliberately bad one. [2:17] Let’s imagine someone says, “I’m out of petrol”, [2:20] and in reply, I say, “there’s a garage down the road”. [2:24] Without context, just using the super-literal, logical meaning of those sentences, [2:28] there’s no connection there. [2:31] Those are just two factual statements. [2:32] But if you assume I’m trying to follow the Cooperative Principle, [2:36] then you can automatically work out a lot more. [2:40] Using the Maxim of Relation, the garage probably has petrol. [2:45] Using the Maxim of Quantity, we know that that's all I need to say in order to imply: [2:50] hey, you can push your car there, you can buy fuel, [2:52] and you can solve your whole "being stranded" problem. [2:54] A problem which, by the way, [2:55] was also completely implied using the Cooperative Principle. [2:59] We can bring the graphics in now, but until this moment, [3:02] all that backstory about a stranded car was implied just by the words “I’m out of petrol”. [3:09] Now, using the Maxim of Quality, we can assume I’m telling the truth [3:11] and this isn't a lie or a guess. [3:13] And using the Maxim of Manner, even someone who’s confused by my dialect [3:18] can work out that "garage" probably means the British slang [3:21] for what Americans would call a “gas station”. [3:24] It’s not just someone’s garage at home where they park their car. [3:28] That would be weird. [3:29] All that got implied from just the phrase “there’s a garage down the road”. [3:34] But what about when we don't follow the Maxims? [3:37] Grice says that in that case, we’re asking for Conversational Implicature. [3:42] Which is to say, we are implying something not said. [3:47] There are two ways to break a maxim: you can “violate” it or you can “flout” it. [3:51] Violating it is just, like, lying. [3:53] It’s breaking a maxim to deceive. [3:55] But “flouting” is breaking a maxim in a way [3:57] that you expect the other person to pick up on. [4:01] One of Grice’s examples is a philosophy professor who has to write [4:04] a grad school letter of recommendation for a student that they have no faith in. [4:08] And, yes, I absolutely believe [4:10] that this is just Grice quietly grumbling about one of his students. [4:13] Anyway, the professor writes the letter using the Cooperative Principle. [4:17] "The student’s command of English is excellent, [4:20] "and his attendance at tutorials has been regular.” [4:25] That is, technically, a letter of recommendation, [4:28] but it doesn’t follow the Maxim of Quantity. [4:30] It is far too little information. [4:31] It doesn’t say the student’s actually good at philosophy. [4:35] It’s flouting the maxim, and when someone does that, [4:37] they are hoping that the person reading or listening will understand [4:41] what they’re really trying to communicate. [4:43] And that’s why you see product packaging that says “vegan tomato” [4:47] or “asbestos-free cereal”, [4:49] or, more realistically, “low in fat” or “low in sugar”. [4:52] They’re flouting Grice’s maxims to imply that the other brands aren’t, [4:57] or to imply that those claims are good things to be. [5:00] And that might not be true. [5:01] But it’s not technically lying. [5:03] It’s just not playing fair by the Cooperative Principle. [5:07] Either that, or there really is some sort of evil, [5:10] animal-byproduct tomato out there. [5:11] Thanks to my co-authors Molly Ruhl and Gretchen McCulloch. [5:14] Gretchen’s podcast Lingthusiasm is linked in the description, it is well worth a listen.