Lots of fun.

Main thesis: We evolved surrounded by mind readers with an instinct to punish cheaters, so we evolved a ‘press secretary’ which comes up with justification for our selfish acts. It works better with plausible deniability, so we are often only consciously aware of the justification and not the underlying motive. Or at the very least, we flinch away from examining the underlying motives.

Explains many examples of irrationality - it’s a feature, not a bug.

Not controversial in cognitive science. Many contribution here (other than great writing) is applying this idea to analyze institutions.

Social status - dominance vs prestige. (Reliably measurable in humans by ratios of eye contact when speaking vs listening!)

Cooperation => coalitions => politics.

Honest signals - ones which are inherently hard to fake. (Analysis made trickier in humans by counter-signaling).

Norm - any societal rule that is primarily enforced by punishment from a 3rd-party coalition, rather than direct retaliation.

(Possibly enabled in humans not just by language but also by weapons and throwing, both of which reduce size/strength advantages and allow groups of weak animals to cooperatively punish a strong animal with relatively low risk to themselves).

Gossip and reputation as an indirect means of enforcing norms. Spreads information and rewards those who punish cheaters.

Meta-norm - often punish people for not enforcing norms or reward people for enforcing norms - incentives norm enforcement in general.

Many norms regulate intentions as well as actions, so we can cheat by believing we have acceptable intentions. Eg bragging vs justified pride, socializing vs sycophancy, organizing vs political manipulation etc.

Common knowledge - risky to punish norm violation if we aren’t sure that other people will agree. So can sometimes cheat with flimsy cover - don’t have to convince anyone, just have to convince them that other people might be convinced.

Subtlety, innuendo, body language all useful because they are deniable - they make violations hard to convincingly report to others.

I’m confused as to why physical tells exist. Why not evolve perfect poker faces?

Other explanations of self-deception (eg protecting our ego) don’t make sense - why not just make the ego less delicate. Has to explain how self-deception leads to better material outcomes in the world.

Incentives that begin and end within one’s own head ultimately lead nowhere, whereas external incentives have real consequences, both material and biological.

Confabulation/rationalization - post-hoc reason generation.

Much body language is an honest signal eg open postures make you more vulnerable eg calling attention to yourself will be punished if others don’t agree that you are high-status.

Laughter well explained as a play signal - “it’s ok, I’m not taking this seriously”. Along with smiling, exaggerated/telegraphed movements and expressions, play screams. Explains laughing at people too - signaling that you don’t take their pain seriously.

Play useful for learning/exploring norms, which is why kids laugh at potty humor and adults joke about sex and politics. Also because it is deniable - just a joke.

As Oscar Wilde said, “If you want to tell people the truth, make them laugh; otherwise they’ll kill you.”

Conversation can’t be about trading information - if it was we would prefer listening to speaking, track conversational debts, jump from topic to topic as we convey the most valuable info we have, and never bother with small talk. Instead, makes sense as demonstration of knowledge and social skill, implying that we would make a good ally. (Sticking to the topic shows that we can produce knowledge on demand, rather than just on a single topic we know about.)

Similarly, we don’t pay much attention to the accuracy or value of the news we consume. Just a large-scale conversation, in which we have to stay on topic (only the latest news) and where we prefer confident, fast-talking (ie prestigious) pundits to accurate ones.

Conspicuous consumption to signal wealth, loyalty to some subculture, awareness of social trends, intelligence (eg a large bookshelf) etc.

‘Lifestyle advertising’ not good at directly creating associations, but builds a common-knowledge signaling language. Eg ads for expensive cars are not shown selectively to rich people, because they need everyone to know that the car is expensive for it to provide status. Explains why socially visible products are more often advertised by lifestyle advertising than personal products eg toothpaste ‘makes your teeth white’ vs vodka ‘cool people drink this in fancy clubs’.

Quality of art depends on the perceived skill of artist - if you find out they just ran a photo through an image filter then it’s no longer art. Claims switch from realism to impressionism etc was triggered by photography - realism is now attainable by everyone, so demonstrating skill requires something else.

Good taste is required for correctly evaluating the artist, so taste becomes valuable in turn.

Most charitable actions are not remotely efficient, but they are highly visible and tend to prefer well-known (ie common-knowledge worthy) causes.

Education more useful for signaling conscientiousness, discipline, willingness to conform to expectations etc (traits that are hard to detect cheaply) than for transmitting knowledge and skills. Explains why schools don’t follow basic principles of learning that have been known for decades.

Schools also do a good job of domesticating/civilizing humans - hierarchies and 9-5 jobs don’t come naturally but our current society can’t function without them.

Various natural experiments show that people consume medicine at a level beyond what actually benefits them. Conspicuous caring on behalf of medical staff, politicians, employers (via insurance) etc. Patients don’t pay much attention to eg hospital track records but do insist on doctors with years of prestigious training even though nurses do just as well in randomized trials.

Religion - cooperative communities that require expensive signaling to enter - deters parasites. Extreme examples like celibate priests and suicide bombers possibly explained by local hill-climbing behavior on a volcano-shaped curve - still a good strategy on average.

(1) People who believe they risk punishment for disobeying God are more likely to behave well, relative to nonbelievers. (2) It’s therefore in everyone’s interests to convince others that they believe in God and in the dangers of disobedience. (3) Finally, as we saw in Chapter 5, one of the best ways to convince others of one’s belief is to actually believe it. This is how it ends up being in our best interests to believe in a god that we may not have good evidence for.

Politics as a performance demonstrating coalition loyalty - profess irrational beliefs, disdain compromise (shows lack of loyalty to the cause). One-dimensional politics arise by merging various coalitions, and focusing on the most extreme differences as the best demonstrator of loyalty.

Need to understand the underlying incentives in order to improve systems, otherwise you’ll find yourself inexplicably swimming upstream.