Difficulty: Intermediate. Prerequisites: Chapters 1–6 (attitudes, conformity, research methods).
Chapter 7 unpacks how persuasion works: who says what, by what channel, to whom. Chapter 8 examines how groups amplify individual tendencies, for better and worse, through social facilitation, social loafing, deindividuation, group polarisation, and groupthink. Chapter 9 turns to prejudice, covering its nature, social and motivational roots, cognitive machinery (categorisation, stereotypes), and real-world consequences.
Persuasion follows two routes: a central route (strong arguments, lasting change) and a peripheral route (surface cues, fleeting change). Groups intensify whatever tendencies members bring in, which can lead to polarisation and groupthink. Prejudice is an attitude (affect + behaviour tendency + cognition) sustained by social inequalities, conformity, categorisation, and the human need for status and belonging.
Persuasion
The process by which a message induces change in beliefs, attitudes, or behaviours.
Central route to persuasion
Occurs when interested people focus on the arguments and respond with favourable thoughts. Produces more enduring attitude change.
Peripheral route to persuasion
Occurs when people are influenced by incidental cues (speaker attractiveness, mood) rather than argument quality. Change tends to be temporary.
Credibility
Believability. A credible communicator is perceived as both expert and trustworthy.
Sleeper effect
A delayed impact of a message: we remember the message but forget why we discounted it, so a message from a low-credibility source gains persuasive power over time.
Foot-in-the-door phenomenon
People who agree to a small request are more likely to comply later with a larger request.
Lowball technique
People who agree to an initial deal often stick with it even after the terms worsen.
Door-in-the-face technique
After someone turns down a large request, the requester counteroffers with a smaller, more reasonable one.
Primacy effect
Information presented first usually has the most influence.
Recency effect
Information presented last sometimes has the most influence (less common than primacy).
Need for cognition
The motivation to think and analyse. People high in need for cognition are more influenced by argument quality (central route).
Attitude inoculation
Exposing people to weak attacks on their attitudes so they can build defences against stronger attacks later.
The communicator – credibility (expertise + trustworthiness) and attractiveness/liking. Speaking confidently and fluently enhances perceived expertise.
The message – reason vs. emotion matters. Good feelings enhance persuasion; fear appeals work when they provide a clear action step. Two-sided appeals are more persuasive when the audience will encounter opposing views.
The channel – face-to-face is most persuasive for complex messages. Media influence often flows through opinion leaders (two-step flow of communication).
The audience – age matters (generational explanation: attitudes formed young tend to persist). Forewarning allows counterarguing. Distraction disarms counterarguing. Uninvolved audiences rely on peripheral cues.
Attitude inoculation works like a vaccine: exposure to weakened versions of opposing arguments builds resistance. Developing counterarguments and the poison parasite defence (combining strong counterarguments with elements that mirror an opponent's messaging) are practical strategies.
Group
Two or more people who interact, influence one another, and perceive one another as "us."
Social facilitation
The strengthening of dominant responses in the presence of others. Simple or well-learned tasks improve; complex or new tasks worsen.
Evaluation apprehension
Concern for how others are evaluating us (one explanation for social facilitation).
Social loafing
Exerting less effort when pooling efforts toward a common goal than when individually accountable.
Free riders
People who benefit from the group but give little in return.
Deindividuation
Loss of self-awareness and evaluation apprehension in group situations that foster responsiveness to group norms, whether good or bad. Promoted by group size, anonymity, and arousing activities.
Group polarisation
Group-produced enhancement of members' preexisting tendencies; a strengthening of the average tendency, not a split.
Pluralistic ignorance
A false impression of what most group members are thinking or feeling.
Groupthink
The mode of thinking in which concurrence-seeking becomes so dominant in a cohesive group that it overrides realistic appraisal of alternatives. Irving Janis identified conditions (amiable cohesive group, isolation from dissent, directive leader) and eight symptoms.
Minority slowness effect
People with minority views express them more slowly than those in the majority.
Transformational leadership
Leadership that exerts significant influence through a leader's vision and inspiration.
Norman Triplett (1898) noticed cyclists raced faster together than alone. The arousal explanation: the presence of others increases arousal, which strengthens dominant responses. Three possible causes of that arousal: evaluation apprehension, distraction, and mere presence.
Social loafing increases when individual contributions are not identifiable. Deindividuation occurs when group size, anonymity, and arousing activities diminish self-awareness. Online anonymity can increase callous behaviour for the same reason.
Discussion typically strengthens the average inclination of group members. This is driven by informational influence (the arguments heard during discussion) and normative influence (the desire to align with or outdo the group's perceived position).
Janis's eight symptoms fall into three clusters: overestimation of the group (illusion of invulnerability, unquestioned morality), closed-mindedness (rationalisation, stereotyped view of opponents), and pressures toward uniformity (conformity pressure, self-censorship, illusion of unanimity, mindguards).
Prevention strategies: be impartial, encourage critical evaluation, subdivide the group then reunite, welcome outside critiques, hold a "second-chance" meeting.
Groups with diverse perspectives outperform groups of like-minded experts, and groups that make smart decisions tend to have widely distributed conversations.
Minority influence depends on consistency, self-confidence, and defection from the majority. A lone defector from the majority can be even more persuasive than a consistent minority voice. Task leadership organises work; social leadership builds teamwork; transformational leadership inspires through vision.
Prejudice
A preconceived negative judgement of a group and its individual members. An attitude combining affect (feelings), behaviour tendency (inclination to act), and cognition (beliefs/stereotypes).
Stereotype
A belief about the personal attributes of a group. Sometimes overgeneralised and inaccurate, sometimes containing a kernel of truth.
Discrimination
Unjustified negative behaviour toward a group or its members.
Social dominance orientation
A motivation to have one's group dominate other social groups.
Authoritarian personality
A personality disposed to favour obedience to authority and intolerance of outgroups.
Social identity
The "we" aspect of self-concept, drawn from group memberships.
Ingroup bias
The tendency to favour one's own group.
Outgroup homogeneity effect
Perceiving outgroup members as more similar to one another than ingroup members are. "They are alike; we are diverse."
Realistic group conflict theory
Prejudice arises from competition between groups for scarce resources.
Group-serving bias
Explaining away outgroup members' positive behaviours while attributing negative behaviours to their dispositions.
Just-world phenomenon
Believing the world is just and that people get what they deserve.
Stereotype threat
A disruptive concern that one will be evaluated based on a negative stereotype. Unlike self-fulfilling prophecy (which works gradually through reputation), stereotype threat has immediate performance effects.
Subtyping
Accommodating individuals who deviate from a stereotype by treating them as "exceptions to the rule."
Subgrouping
Accommodating deviations by forming a new stereotype about a subset of the group.
Prejudice can be explicit (conscious) or implicit (automatic). Racial prejudice has become more subtle (employment discrimination, patronising behaviour). Gender prejudice mixes benevolent sexism ("women are wonderful") with hostile sexism. LGBT prejudice persists through job discrimination, harassment, and rejection.
Unequal status breeds prejudice and justifies itself (e.g. historical justification of slavery). Socialisation transmits prejudice from parents and peers. The authoritarian personality predisposes some individuals. Conformity means that when prejudice is socially accepted, many follow the path of least resistance; when norms change, prejudice can diminish.
Systemic supports include institutional policies and media portrayals that reinforce stereotypes (e.g. photography bias toward men's faces and women's bodies).
Frustration feeds hostility and can be displaced onto scapegoats (displaced aggression). Competition for scarce resources intensifies intergroup prejudice (realistic group conflict theory). Social identity theory explains ingroup bias: we categorise, identify with our ingroup, and compare favourably with outgroups to bolster self-esteem.
Categorisation is cognitively efficient but overgeneralises. We rely more on stereotypes when pressed for time, preoccupied, or tired. The outgroup homogeneity effect makes "them" seem more alike than "us." Distinctive people and events attract disproportionate attention, fostering illusory correlations. Group-serving bias and the just-world phenomenon complete the cognitive picture.
Prejudgements guide attention and memory. Stereotype threat can immediately impair performance. Discrimination creates self-fulfilling prophecies that confirm the prejudice.
Students often confuse the central and peripheral routes. The central route requires motivation and ability to process arguments; the peripheral route relies on surface cues. The route depends on the audience's involvement, not the message's quality alone.
Students assume group polarisation means the group splits into opposing camps. It does not. It means the group's average position becomes more extreme in whichever direction it was already leaning.
Students think prejudice is only about conscious, overt hostility. Modern prejudice is often implicit and subtle, operating below awareness.
Students confuse stereotype threat with self-fulfilling prophecy. Stereotype threat is an immediate, situational anxiety; self-fulfilling prophecy works gradually over time through changed expectations and behaviour.
⚠️ Know the four elements of persuasion (communicator, message, channel, audience) and be able to apply them to a scenario.
⚠️ Distinguish the central and peripheral routes, including when each is more likely and which produces more lasting change.
⚠️ Know the eight symptoms of groupthink and the three clusters they fall into (overestimation, closed-mindedness, uniformity pressure).
⚠️ Be able to explain group polarisation using both informational and normative influence.
⚠️ Social identity theory (categorise, identify, compare) is a major framework. Know it well.
⚠️ Understand the difference between subtyping and subgrouping as ways stereotypes survive disconfirming evidence.
True or False: The peripheral route to persuasion produces more enduring attitude change than the central route. (False. The central route produces more lasting change.)
Fill in the blank: The tendency to exert less effort in a group is called social ________. (Loafing.)
True or False: Group polarisation means groups become more moderate after discussion. (False. Groups shift toward the extreme of their initial average position.)
Fill in the blank: The "they are alike; we are diverse" perception is called the ________ homogeneity effect. (Outgroup.)
True or False: Attitude inoculation involves exposing people to strong attacks on their beliefs. (False. It uses weak attacks to build resistance.)
Q: A company wants to sell a complex product to well-informed buyers. Should the advertising take the central or peripheral route? Why?
A: Central route. Well-informed, motivated buyers are likely to scrutinise arguments. Persuasion through strong evidence and logical reasoning will produce more durable attitude change than attractive spokespeople or catchy jingles.
Q: Explain how groupthink contributed to a real-world disaster such as the Challenger shuttle explosion.
A: Engineers at Morton Thiokol warned against launching in cold temperatures, but the cohesive decision-making group was isolated from dissent, led by a directive leader, and subject to conformity pressure. Symptoms included illusion of invulnerability, self-censorship, and mindguards shielding the group from disconfirming information.
Q: How does social identity theory explain ingroup bias?
A: We categorise people into groups, identify with our ingroup, and compare our group favourably with outgroups. This favourable comparison bolsters self-esteem, which motivates us to maintain positive distinctions between our group and theirs.
Persuasion techniques (foot-in-the-door, door-in-the-face) connect back to the attitudes-follow-behaviour principle from Chapter 4. Group polarisation (Chapter 8) explains why juries, boards, and online communities become more extreme, which links to the conformity material in Chapter 6. Social identity theory and ingroup bias (Chapter 9) connect forward to conflict and peacemaking in Chapter 13, where superordinate goals and equal-status contact are introduced as remedies.
Persuasion, central route, peripheral route, elaboration likelihood model, credibility, sleeper effect, attractiveness, foot-in-the-door, lowball, door-in-the-face, primacy effect, recency effect, two-step flow, need for cognition, attitude inoculation, group, social facilitation, evaluation apprehension, social loafing, free riders, deindividuation, group polarisation, risky shift, pluralistic ignorance, groupthink, Janis, minority influence, minority slowness effect, transformational leadership, task leadership, social leadership, prejudice, stereotype, discrimination, implicit bias, explicit bias, social dominance orientation, authoritarian personality, social identity theory, ingroup bias, outgroup homogeneity, realistic group conflict, scapegoat theory, group-serving bias, just-world phenomenon, stereotype threat, subtyping, subgrouping, benevolent sexism, hostile sexism