Emotions and Social


The brain is origin of mental life:

  • The Astonishing Hypothesis by Francis Crick
  • Darwin’s Dangerous Idea by Daniel Dennett

Intelligent Design, aka creationism.

The misconception of evolution and psychology:

Distinction ultimate causation(why something is evolved) between proximate causation(what creature want).

Natural selection entails that everything is adaptive:

  • some are accidents.
  • some are not adapted yet due to the fast pace of technology advance.

Life is impossible without emotions

Facial expressions

Different smiles, even baby can distinguish them

  • Duchenne smile, the real smile.
  • Pan Am smile, greeting smile
  • Coy smile, — I am adorable, please don’t kill me.

Genuine emotion is hard to fake, they are trustworthy signals.


Nature, red in tooth and claw

We are evolved altruists, coined by Richard Dawkins.

  • Animals are vehicle of genes.
  • The genes who successfully reproduce win.

The gene with discriminate altruism has better chance to survive, aka kin selection.

Selfish genes lead to unselfish animals.


  • The cupboard theory by Skinner: mother provides milk
  • Innate attachment by Bowlby: comfort, fear of strangers.

Reciprocal altruism(Trivers): the cheater must be punished.

Prisoner’s dilemma

The competition of prisoner’s dilemma, the winning strategy was Tit-for-Tat, proposed by Anatol Rapoport:

  • Cooperate first
  • Do on each trial what the other program did on previous trial.

Irrationality has an edge as crazy person is hard to predict. The reputation of irrationality may lead to be better off, only if within the culture context.

The emotions having evolutionary roots, can be calibrated by culture.


The unconscious bias, social priming.


The spotlight effect.

Lake Wobegon effect

All the children are above average

Self & Others

Self-serving bias: attribute the failures to others.

Cognitive Dissonance Theory

  • Avoiding inconsistent information, aka confirmation bias.
  • Insufficient justification effect. We need to find the justifications to do things we dislike.

Attribution Theory


We intuitively attribute others’ actions to personality characteristics.

Not enough weight on situational factors.


The first three are the same factors for [[Week 3 Perceptions#^951037]]

  • Familiarity
  • Proximality
  • Similarity
  • Attractiveness, — Mathew effect.

Q: Why Mathew effect helps the evolution?

First impression is powerful, thin slices. The perceptions are also self-fulfilling, aka self-reinforcement, pygmalion effect.


We generalize individuals to groups.

  • Sterotype
  • Racism

Stereotypes are often positive and accurate, but are not always accurate, and enforced by the confirmation bias. We also take groups seriously even when the groups are setup arbitrarily.

Project Implicit