Difficulty: Intermediate | Prerequisites: Chapters 1 and 3
These two chapters ask: where does social behaviour come from? Chapter 4 looks at the self (how we present ourselves, how we handle contradictions in our own thinking). Chapter 5 zooms out to the biological and cultural forces that shape behaviour, including evolution, gender and norms. Together they bridge the individual-level cognition of Chapter 3 and the group-level processes of Chapter 6 onward.
We manage how others see us (self-presentation) and we reduce internal tension when our actions clash with our beliefs (cognitive dissonance). Our social behaviour is also shaped by biology (genes, evolution, sex differences) and culture (norms, individualism vs collectivism). Neither biology nor culture alone explains behaviour; they interact continuously.
Self-presentation (impression management)
The process by which we try to control the impressions others form of us. Self-presentation theory assumes we express attitudes that make us appear consistent. Think of it as: curating your social media profile so people see the version of you that you want them to see.
Cognitive dissonance
The tension that arises when a person is simultaneously aware of two inconsistent cognitions (beliefs, attitudes or behaviours). In simple terms, the uncomfortable feeling you get when your actions do not match your beliefs.
Selective exposure
The tendency to seek information and media that agree with one's existing views and to avoid information that contradicts them. Think of it as: reading only news outlets that already share your politics.
Insufficient justification
A dissonance-reduction mechanism in which, lacking strong external reasons for a behaviour, a person internally justifies it by changing their attitude. In simple terms, if nobody forced you to do something, you convince yourself you must have wanted to.
Natural selection
The evolutionary process by which heritable traits that improve survival and reproduction are passed on to future generations. Think of it as: nature's way of keeping traits that work and dropping traits that do not.
Evolutionary psychology
The study of how evolutionary principles (especially natural selection) shape cognition and behaviour. In simple terms, asking: why might our ancestors have developed this particular way of thinking or acting?
Sex
The two biological categories of male and female.
Gender
In psychology, the characteristics, whether biological or socially influenced, that we associate with males and females. In simple terms, sex is what biology assigns; gender includes the social meaning layered on top.
Culture
The enduring behaviours, ideas, attitudes and traditions shared by a large group of people and transmitted from one generation to the next. Think of it as: the invisible operating system of a society.
Norms
Standards for accepted and expected behaviour within a group or culture. In simple terms, the unwritten rules about what is considered "normal" or "proper."
Personal space
The buffer zone we prefer to maintain around our bodies during social interaction. Its size varies across cultures.
Self-presentation theory says we strategically express attitudes that make us look consistent and socially desirable.
This is not necessarily dishonest. Most people genuinely want to be seen the way they see themselves.
When behaviour and belief clash, the resulting tension (dissonance) motivates us to change one or the other.
Common dissonance-reduction strategies: change the behaviour, change the belief, add new cognitions that justify the inconsistency.
Selective exposure reinforces dissonance reduction: we surround ourselves with information that confirms we made the right choice.
Insufficient justification: when there is no strong external reason for a behaviour (no big reward, no serious threat), people are more likely to shift their attitudes to match their behaviour. The classic example is the "boring task" experiment: participants paid $1 to lie about a dull task later reported enjoying it more than those paid $20, because $1 was not enough external justification.
Humans share hundreds of universal behaviours and language patterns across cultures.
These commonalities arise from our biological similarity and define our shared human nature.
Natural selection favours heritable traits that aid survival and reproduction.
Evolutionary psychology applies these principles to cognition and behaviour, but cultures also provide specific rules that shape how biology is expressed.
Sex refers to biological categories. Gender refers to the characteristics we associate with males and females, whether biologically or socially influenced.
Some people identify as gender-fluid or non-binary; transgender individuals have a psychological sense of gender that differs from their birth sex.
One well-replicated sex difference: men report thinking about sex more frequently and desiring more sexual partners. Evolutionary psychologists explain this as the result of different adaptive challenges in reproduction.
Critics of evolutionary psychology argue it often works backward from a finding to construct a plausible-sounding story, and that cultural explanations use hindsight just as much.
Culture is the enduring set of behaviours, ideas, attitudes and traditions shared by a group and passed across generations.
Much of our behaviour is socially programmed: language, customs, expressiveness, punctuality.
Norms prescribe what is considered proper, describe what is considered normal, and can feel arbitrary to outsiders.
When norms are unclear, we monitor others and adjust accordingly.
Cultures differ along several dimensions:
Individualism vs collectivism
Expressiveness
Rule-following and tightness vs looseness of norms
Personal space
Cognitive dissonance is used in marketing (the "foot-in-the-door" technique relies on insufficient justification) and in therapy (encouraging small behavioural changes that shift attitudes). Understanding cultural norms is essential in international business, diplomacy and any context where people from different backgrounds interact.
Students often think cognitive dissonance is the same as hypocrisy. Hypocrisy is a social accusation; dissonance is a psychological state of tension that motivates change. You can experience dissonance without anyone else knowing.
Students assume evolutionary explanations mean behaviour is fixed. Evolution prepared us to adapt; culture changes, and behaviour changes with it.
Students confuse sex and gender. Sex is the biological category. Gender includes the socially constructed meanings attached to those categories. The course treats them as related but distinct.
Students sometimes think "norms" means "rules that are written down." Most norms are unwritten. You learn them by watching what other people do and by feeling the discomfort of violating them.
⚠️ Cognitive dissonance is a staple exam topic. Be ready to explain the mechanism and to apply it to a novel scenario (e.g. someone who buys an expensive product and then convinces themselves it was the best choice).
⚠️ Know the difference between insufficient justification and selective exposure. Both reduce dissonance, but by different routes.
⚠️ The sex vs gender distinction is commonly tested. Be precise with definitions.
⚠️ Expect a question asking you to evaluate evolutionary psychology: what are its strengths (it generates testable predictions) and weaknesses (post-hoc storytelling, difficulty testing ultimate vs proximate causes)?
⚠️ Cultural dimensions (individualism vs collectivism, tight vs loose norms) often appear as short-answer or comparison questions.
Fill in the blank: The uncomfortable tension from holding two contradictory beliefs is called ________. (Cognitive dissonance.)
True or false: Selective exposure means deliberately seeking out information that challenges your views. (False, it means seeking information that agrees with your views.)
Fill in the blank: ________ is the study of how evolutionary principles shape cognition and behaviour. (Evolutionary psychology.)
True or false: Sex and gender mean the same thing in psychology. (False, sex is biological; gender includes socially constructed characteristics.)
Fill in the blank: The unwritten rules about accepted and expected behaviour within a group are called ________. (Norms.)
Q: Explain how cognitive dissonance works and give an original example.
A: Cognitive dissonance is the tension from holding two contradictory cognitions at once. To reduce it, people change one cognition or add a new one. Example: a person who values health but smokes may reduce dissonance by quitting, by downplaying the health risks, or by adding the belief that smoking reduces stress.
Q: What is insufficient justification, and how does it differ from selective exposure?
A: Insufficient justification occurs when a person lacks a strong external reason for a behaviour and therefore shifts their internal attitude to match it. Selective exposure is the tendency to seek information that confirms an existing belief. Both reduce dissonance, but insufficient justification changes an attitude while selective exposure protects one.
Q: What is one strength and one weakness of evolutionary psychology as an approach to understanding social behaviour?
A: Strength: it generates testable predictions about universal human tendencies (e.g. mate preferences across cultures). Weakness: it often works backward from a known finding to construct an explanation, making it difficult to distinguish a genuine evolutionary account from a plausible story.
Q: Define norms and explain how they function in everyday social life.
A: Norms are standards for accepted and expected behaviour. They prescribe what is proper, describe what is normal, and are enforced informally through social approval and disapproval. When norms are unclear, people monitor others and adjust their own behaviour accordingly.
Q: Compare individualist and collectivist cultures on the dimension of personal choice.
A: In individualist cultures, personal autonomy and self-expression are emphasised; people are expected to make their own choices and stand out. In collectivist cultures, group harmony and social obligations take priority; choices are made with the group's interests in mind.
Cognitive dissonance connects back to confirmation bias and selective exposure from Chapter 3. The nature-vs-nurture theme runs through every subsequent chapter, especially when discussing aggression, altruism and prejudice. Cultural norms feed directly into Chapter 6 on conformity (Sherif's norm-formation studies). Individualism vs collectivism is a dimension that returns whenever the course compares findings across cultures.
self-presentation, impression management, cognitive dissonance, Festinger, selective exposure, insufficient justification, $1/$20 experiment, natural selection, evolutionary psychology, sex, gender, transgender, non-binary, gender fluid, culture, norms, individualism, collectivism, tight vs loose cultures, personal space, nature vs nurture, universal behaviours, adaptive traits, mate selection, cultural diversity