Group dynamics: conformity (Asch), obedience (Milgram), groupthink, social loafing

Intuition Beginner

We like to think we are independent, but the group shapes our behavior more than we realize. In the 1950s, Solomon Asch showed that people would deny the evidence of their own eyes — agreeing that a line was shorter when everyone else in the room (actually actors) said the wrong answer. About 75% of participants conformed at least once.

Stanley Milgram took this further. He told volunteers to deliver increasingly powerful electric shocks to a learner — an actor who screamed — for wrong answers. Despite the screams, 65% went to the maximum 450 volts when an authority figure told them to continue. The lesson: ordinary people can do harmful things under social pressure.

Groupthink occurs when cohesive groups prioritize harmony over good decision-making. President Kennedy's advisors fell into it during the Bay of Pigs invasion, suppressing doubts about a flawed plan. Social loafing is a related pattern: people exert less effort in a group than alone, a finding first measured by pulling on ropes.

Together these phenomena show that the situation — not just character — drives behavior. Knowing the mechanisms is the first step toward resisting them, which is why these studies are taught in every introductory course.

Visual Beginner

Figure: The four core group-dynamics phenomena. Asch's conformity paradigm shows unanimous-majority pressure overriding the evidence of one's senses. Milgram's obedience paradigm shows authority overriding conscience, graded by victim and authority proximity. Janis's groupthink model catalogues the symptoms that make cohesive groups decide badly. Social loafing tracks declining per-person effort as group size grows.

Worked example Beginner

The Asch line-judgment paradigm

Solomon Asch gathered eight male participants in a room for what they were told was a visual-perception study. Only one was a real participant; the other seven were confederates working with the experimenter. The group was shown one card with a standard line and another with three comparison lines, one of which plainly matched the standard.

Each person stated their answer aloud, in order. The real participant sat next-to-last. On the first two trials everyone agreed on the correct line. On the third trial, and on eleven more critical trials that followed, all seven confederates gave the same plainly wrong answer. The participant now faced a choice: trust his eyes, or go along with the group.

The result: across the critical trials, participants conformed on about 37% of responses. About 75% conformed at least once; only about 25% never conformed at all. In a control condition with no group pressure, errors were under 1%. When Asch planted a single dissenting confederate who gave the correct answer, conformity collapsed — a single ally was enough to break the spell.

The study isolates one variable: a unanimous majority. No reward, no threat, no authority figure — only the discomfort of being the lone dissenter. That discomfort was enough to make most people deny what they saw.

Check your understanding Beginner

Formal definition Intermediate

The vocabulary of social influence and group dynamics is standardised across the anchor texts ^{[source pending]}. The terms below identify empirically dissociable mechanisms, not mere labels, and the boundaries between them carry theoretical weight.

Conformity is a change in behavior or belief owing to real or imagined group pressure, whether or not there is explicit demand. Herbert Kelman distinguished three varieties whose psychological depth differs ^{[source pending]}. Compliance is public conformity without private acceptance — the person goes along to gain approval or avoid rejection, but the underlying belief is unchanged. Identification is conformity to a liked or respected group or person, adopted because of a relationship and dropped when the relationship ends. Internalization is the deepest form: the person genuinely accepts the belief because it is congruent with their value system, making it durable and resistant to later counter-pressure. Compliance is situational; internalization is structural.

Asch conformity (1956). In the line-judgment paradigm, participants conformed on roughly 37% of critical trials; about 75% conformed at least once ^{[source pending]}. Several factors modulate the rate:

Factor	Effect on conformity
Unanimity of majority	Conformity is high; a single dissenter collapses it
Group size	Increases up to about 4–7 confederates, then plateaus
Anonymity of response	Written (private) responses reduce conformity
Status / competence of majority	Higher-status majorities elicit more conformity
Culture (collectivist vs individualist)	Collectivist cultures show higher conformity (Bond-Smith 1996 meta-analysis)
Task difficulty / ambiguity	Ambiguous judgments raise conformity

Milgram obedience (1961–1963). In the baseline condition, 65% of participants delivered the maximum 450 volts. Milgram proposed that obedience places a person in an agentic state, in which the individual cedes responsibility for their actions to the authority and becomes an instrument of the authority's will — contrasted with the autonomous state, in which the individual accepts responsibility for (and governs) their own conduct ^{[source pending]}. Obedience varied sharply with situational factors: victim proximity (same room dropped obedience to 40%; hand-on-plate to 30%), authority proximity (orders by telephone dropped it sharply; no authority present meant near-zero compliance), institutional setting (a run-down office building dropped obedience to 48%), and the presence of rebellious confederates (dropped to 10%).

Groupthink (Janis, 1972). Irving Janis's model describes a mode of thinking that cohesive groups fall into "when the members' strivings for unanimity override their motivation to realistically appraise alternative courses of action" ^{[source pending]}. The symptoms cluster into three categories:

Antecedents	Symptoms	Decision defects
High group cohesion	Illusion of invulnerability	Incomplete survey of alternatives
Structural isolation	Belief in inherent morality	Failure to re-examine preferred choice
Directive leadership	Collective rationalisation	Poor information search
High stress / time pressure	Stereotyping of out-groups	Selective bias in processing information
Recent failures	Pressure on dissenters	Failure to work out contingency plans
	Self-censorship
	Illusion of unanimity
	Self-appointed mindguards

Prevention is procedural: leaders should state their preference last, invite outside experts, divide into independent subgroups, hold second-chance meetings, and assign a devil's advocate. Janis's cases include the Bay of Pigs invasion (1961), Pearl Harbor (1941), the escalation of Vietnam, and the Challenger disaster (1986).

Social loafing (Ringelmann effect). Max Ringelmann (1913) found that per-person effort in rope-pulling declines as group size grows. The effect generalises across clapping, shouting, brainstorming, and swimming-team performance. The mechanism is diffusion of responsibility: when individual output is pooled and unidentifiable, accountability drops. Loafing is reduced by identifiability of contributions, meaningful tasks, group-size salience, and collectivist cultural context.

Social facilitation (Zajonc, 1965). Robert Zajonc resolved a long-standing contradiction — the presence of others sometimes improves and sometimes impairs performance — with drive theory: an audience (or co-actors) raises physiological arousal, which strengthens the dominant response. On simple or well-learned tasks the dominant response is correct, so performance improves; on complex or novel tasks the dominant response is wrong, so performance suffers. Later work (Cottrell, 1972) adds that the effect depends on apprehension about being evaluated, not mere presence.

Social identity theory (Tajfel-Turner). Henri Tajfel and John Turner showed that people derive part of their self-concept from group membership and are motivated to see their in-group as positively distinct. The minimal group paradigm demonstrates that in-group favoritism emerges even from arbitrary categorisation (a preference for one painting over another), with no history of conflict and no material stake ^{[source pending]}.

Key experiment Intermediate

Conformity: Asch's variations and the role of unanimity

The single most important variable in Asch's paradigm is the unanimity of the majority. When Asch planted one confederate who gave the correct answer on critical trials, conformity dropped to about 5% of responses — a near-total elimination of the effect. What broke the spell was not the dissenter's correctness per se but the mere existence of a nonconforming peer: the participant was no longer alone. Variations showed that a dissenter whose answer was also wrong (just wrong in a different way from the majority) still sharply reduced conformity, confirming that independence, not accuracy, is the operative lever.

Group size had a nonlinear effect. With one confederate, conformity was negligible; it rose steeply through two and three confederates, then levelled off at around four to seven. Beyond seven, adding more unanimous voices added little. A unanimous majority of three produces more conformity than a non-unanimous majority of any size. The structural lesson is that conformity is gated by unanimity and by the perception of being a lone deviant, not by sheer head-count.

The mode of response mattered. When participants wrote their answers privately rather than speaking them aloud, conformity dropped substantially, indicating that much of the effect was compliance (public conformity to avoid appearing deviant) rather than internalization (genuine belief change). Yet a residue of conformity persisted even in private responding, consistent with some degree of genuine informational influence — the participant suspects that if everyone else sees a different line, perhaps the majority is right.

Obedience: Milgram's situational variations

Milgram ran over 20 experimental variations, each manipulating one situational feature while holding the participants, the shock generator, and the prods constant ^{[source pending]}. The obedience rate swung from 65% (baseline, remote victim) down to 10% (peer rebellion) depending entirely on the structure of the situation — not on the personality of the participant.

Variation	Obedience to 450V
Baseline (victim in another room)	65%
Victim in same room	40%
Teacher must press victim's hand to plate	30%
Run-down office building (no Yale affiliation)	48%
Experimenter gives orders by telephone	~22%
Two co-teachers (confederates) refuse	10%
Authority present but as ordinary man, not scientist	reduced

The variations isolate the operative variables. Victim proximity raises the salience of the suffering and makes the harm concrete; authority proximity keeps the demand to continue immediate and embodied; institutional setting lends legitimacy to the authority; peer rebellion provides a model of refusal. None of these touches the participant's character — they all reshape the situation — yet together they swing obedience across nearly the full range. Milgram read this as decisive evidence for the power of situational forces over dispositional ones.

Stanford Prison Experiment: role internalisation

In 1971, Philip Zimbardo randomly assigned 24 male college students to be guards or prisoners in a simulated prison ^{[source pending]}. The study was planned for two weeks and terminated after six days, as guards became abusive and prisoners became passive and distressed. Zimbardo interpreted the result as evidence that powerful situational roles overwhelm individual personality. The experiment is treated at length — including its methodological and ethical criticisms — in the master tier, because its evidential status is contested.

Exercises Intermediate

Advanced results Master

Milgram replications and ethical critique

Milgram's findings proved difficult to replicate in full after the rise of modern institutional review boards (IRBs), because the paradigm inflicts precisely the deception and distress that the Belmont Report (1979) was written to prevent. The most consequential modern partial replication is Jerry Burger (2009), who re-ran the paradigm capped at 150 volts — the point at which the learner first demanded to be released ^{[source pending]}. Burger found obedience rates strikingly similar to Milgram's: roughly 70% of participants were willing to continue past 150V, matching Milgram's figure at that breakpoint. Because no participant could proceed beyond 150V, the study cannot speak to the 450V headline figure, but it establishes that the willingness to obey through the learner's first explicit protest has not diminished in four decades.

The ethical critique begins with Diana Baumrind (1964), who argued that the distress Milgram inflicted was neither justified nor adequately anticipated by participants, and that the debrief did not undo the harm of having discovered oneself capable of cruelty. The tension is genuine: modern IRB standards would not approve the original paradigm, yet the knowledge it produced is widely regarded as among the most important in the discipline. The field's resolution is not to repeat the original but to learn what it can from partial replications, archival reanalysis, and the historical record.

Situational vs dispositional accounts: the fundamental attribution error

The deepest theoretical question raised by Milgram and Asch is whether their results reveal situational forces (the power of the social structure) or dispositional ones (something about the kind of people who obey). Lee Ross and Richard Nisbett argued that observers systematically overestimate dispositional factors and underestimate situational ones — the fundamental attribution error ^{[source pending]}. When people learn that 65% of Milgram's participants went to the maximum, their first instinct is to infer a disposition ("those people are cruel," or "Germans are authoritarian"), even though the participants were ordinary volunteers and the variation experiments showed that the situation swings obedience across nearly the full range. The power-of-the-situation reading holds that the same person would behave very differently under different structural conditions, which is exactly what Milgram's variations demonstrated.

The social identity model of tyranny (Haslam-Reicher)

Stephen Reicher and Alexander Haslam mounted the most serious theoretical challenge to Zimbardo's role-assignment account of the Stanford Prison Experiment. In their BBC Prison Study (2001), a replication broadcast on television, they found that tyranny did not emerge automatically from guard roles ^{[source pending]}. Guards who did not identify with the guard group did not become abusive; prisoners who developed a shared social identity resisted collectively. Haslam and Reicher's social identity model of tyranny holds that oppressive behavior emerges not from being assigned a role but from coming to identify with a group whose norms legitimate oppression. Tyranny, on this account, is a group-process phenomenon rooted in social identification, not an automatic consequence of situational casting. This reframes the Stanford findings: the guards were not surrendered to by roles, they were drawn into a shared identity — and that identity was partly constructed by the experimenter's framing, which connects to the demand-characteristics critique.

Participant interpretations: the "engaged followership" critique

A further line of critique, developed by Stephen Reicher and colleagues (including S. Alexander Haslam) and supported by archival work by Naomi Russell and Ian Nicholson, complicates the "blind obedience" narrative. Qualitative reanalysis of Milgram's session transcripts and participant questionnaires suggests that many participants did not believe the shocks were fully real, and that some interpreted the situation as a scientific test of endurance they were helping the experimenter complete ^{[source pending]}. On this reading, obedience is not passive submission to authority but engaged followership — identification with the scientific enterprise and its goals, in which the participant enacts a shared project rather than surrendering agency. The implication is that Milgram's data are consistent with multiple interpretations, and the "obedience to authority" framing, while powerful, may understate the role of participants' active constructions of what they were doing.

The bystander effect and diffusion of responsibility

John Darley and Bibb Latané developed the bystander effect after the 1964 murder of Kitty Genovese, in which (it was reported) 38 witnesses did nothing ^{[source pending]}. Darley and Latané's five-step model of helping specifies that intervention requires noticing the event, interpreting it as an emergency, taking responsibility, deciding how to help, and implementing help. The decisive variable is the diffusion of responsibility: in a crowd, each bystander assumes someone else will act, so individual responsibility is divided and diluted. In their classic experiment, participants seated in individual cubicles and told they were in a group of two, three, or six were far less likely to report a seizure when they believed more bystanders were present — 85% responded with two, 62% with three, 31% with six.

The Kitty Genovese story itself has been substantially revised. Rachel Manning, Mark Levine, and Alan Collins (2007) showed that the "38 witnesses" figure was a journalistic exaggeration, that several witnesses did intervene (one shouted, one called police), and that the ambiguous acoustic environment of the courtyard made the event hard to interpret ^{[source pending]}. The bystander effect (diffusion of responsibility in laboratory studies) is robust; the specific Genovese narrative that crystallised it is partly myth. Modern research extends bystander intervention to online helping and to sexual-assault-prevention programs that train potential bystanders to overcome diffusion of responsibility.

Deindividuation and the SIDE model

Zimbardo's deindividuation research found that anonymity and arousal reduce self-awareness, weakening normal restraints on behavior ^{[source pending]}. The original account held that deindividuation produces unregulated, often antisocial behavior. Reicher's SIDE model (Social Identity Model of Deindividuation Effects) reframes the finding: anonymity does not remove self-regulation but shifts regulation from personal to social identity ^{[source pending]}. Anonymous individuals behave not randomly but in line with the salient group norm. If the group norm is aggressive, anonymity increases aggression; if the norm is prosocial, anonymity increases prosocial behavior. Deindividuation is thus context-dependent conformity to whatever identity is salient, not a collapse into impulse.

Social dilemmas

Group dynamics meet game theory in the study of social dilemmas, situations in which individual rationality produces collective catastrophe. Garrett Hardin's Tragedy of the Commons (1968) models a shared pasture on which each herder gains by adding animals but the pasture is ruined if all do ^{[source pending]}. The prisoner's dilemma formalises the structure: mutual defection is individually rational but jointly worse than mutual cooperation. Robert Axelrod's (1984) computer tournaments showed that tit-for-tat — cooperate first, then mirror the opponent's last move — is a remarkably robust strategy in iterated prisoner's dilemmas, because it is nice (never defects first), retaliatory (punishes defection), forgiving (returns to cooperation), and clear. Public-goods dilemmas (where individuals can free-ride on collective contributions) and resource dilemmas (where individuals over-harvest a common pool) share the same tension between local and global rationality.

Social identity theory and the minimal group paradigm

Tajfel and Turner's minimal group paradigm is among the most striking demonstrations in social psychology ^{[source pending]}. Participants were divided into groups on the basis of meaningless criteria — a preference for one Klee painting over one Kandinsky, or an overestimate versus underestimate of dots — and then asked to allocate money to anonymous in-group or out-group members. Even with no prior interaction, no conflict, and no material stake, participants systematically favored in-group members. Critically, they often chose allocations that maximized the relative advantage of the in-group over the absolute payoff — giving the in-group less in absolute terms if it meant the out-group got even less. The finding implies that prejudice and favoritism do not require competition or realistic conflict; the mere act of categorization, combined with the drive for positive distinctiveness, is sufficient.

Connections Master

• Social psychology: groups, prejudice 29.07.01 is the direct prerequisite and parent unit. The conformity, obedience, bystander, and deindividuation findings introduced there are specialised and deepened here, with the formal definitions, experimental detail, and theoretical controversies that the parent unit surveyed.

• Attitudes and persuasion 29.07.02 pending connects through compliance and identification (Kelman's varieties of conformity overlap with attitude-change mechanisms). The ELM's peripheral route explains why unanimous-majority cues and authority cues are processed without scrutiny, and the boomerang effect parallels the breakdown of obedience under peer rebellion.

• Decision-making and judgment 29.05.02 pending connects through groupthink, which is the group-level analogue of the individual biases catalogued there (confirmation bias, framing, overconfidence). The tragedy of the commons and prisoner's dilemma are shared territory between social psychology and behavioral economics.

• Moral development 29.06.03 pending (pending) connects through the question Milgram forces: at what stage of moral reasoning does a person refuse authority on ethical grounds? Milgram's variations suggest that situational structure dominates stage of reasoning in predicting obedience, a finding that complicates stage theories.

• Conditioning 29.04.02 pending connects through social facilitation as a non-associative arousal effect and through the reinforcement contingencies that maintain compliance and social-loafing behavior.

• Cross-cultural psychology 29.12.01 connects through the Bond-Smith (1996) meta-analysis: collectivist cultures show higher conformity than individualist cultures, and the WEIRD critique applies to group-dynamics research with particular force, since the classic studies were American.

• Neuroscience [29.02.NN] (pending) provides the substrate for the arousal that underlies social facilitation (Zajonc's drive theory) and the neural correlates of social-conformity conflict (anterior cingulate cortex activity tracks the discomfort of dissent).

• Social psychology successor 29.07.04 pending (proposed) extends group-dynamics research into prejudice and discrimination: social identity theory, the minimal group paradigm, and the fundamental attribution error all build directly on the mechanisms catalogued here.

Historical & philosophical context Master

The study of social influence was galvanised by the catastrophe of the Second World War. Solomon Asch, a Polish-born social psychologist who had himself experienced the pressure to conform under authoritarian conditions, designed his conformity experiments in the early 1950s partly in response to the question of how entire populations could be swept into assent to plainly false claims. Asch's answer was not that people are gullible in the way propaganda theory assumed, but that the social structure of unanimous assent exerts a pressure that most individuals find difficult to resist alone. The experiments were a rebuttal both to simplistic accounts of mass persuasion and to the then-dominant conformist account of Sherif's autokinetic effect, in which group norms formed through ambiguity. Asch showed that conformity persists even when the correct answer is unambiguous and visible to the naked eye.

Stanley Milgram's obedience program, begun at Yale in 1961, was motivated by the same historical question — how could ordinary people carry out the ordered atrocities of the Nazi regime — and by the trial of Adolf Eichmann in Jerusalem, which Milgram followed closely. Hannah Arendt's portrait of Eichmann as a banal bureaucrat following orders resonates with Milgram's finding that ordinary volunteers, not sadists, would inflict what they believed were lethal shocks on the authority's instruction. Milgram's own interpretation was agentic-shift theory: in the presence of a legitimate authority, the individual enters a state in which he regards himself as an instrument of the authority's purposes and so no longer governs his own conduct. The interpretation has been contested, but the historical resonance of the question — how is morally catastrophic behavior produced by ordinary people in structured situations — is the reason the experiments remain central.

Irving Janis arrived at groupthink not from the laboratory but from the archival study of foreign-policy fiascos. Victims of Groupthink (1972) compared decisions like the Bay of Pigs, Pearl Harbor, and the escalation of Vietnam with successful deliberations like the Cuban Missile Crisis, and extracted the symptom cluster and antecedent conditions catalogued above. Janis's contribution was to show that cohesion, which is usually treated as a virtue of groups, becomes a liability when it suppresses dissent and critical evaluation. The model has been applied far beyond foreign policy — to corporate boards, medical teams, religious cults, and engineering organisations — and its prescriptions (devil's advocate, second-chance meetings, outside experts) have entered standard practice in group-decision training.

The bystander-effect program (Darley and Latané, 1968) emerged from the Kitty Genovese case, but its theoretical core — diffusion of responsibility in pluralistic settings — had been prefigured by social-loafing research (Ringelmann, 1913) and by general questions about the conditions under which a group inhibits individual action. The Manning-Levine-Collins (2007) revision of the Genovese narrative is itself a methodological lesson: the empirical core of a phenomenon can be robust even when the originating anecdote is partly inaccurate, and the two must be evaluated separately.

The deepest philosophical issue raised by the group-dynamics literature is the situationist challenge to virtue ethics. If, as Milgram's variations show, a person's behavior swings across nearly the full moral range depending on situational structure rather than on stable character traits, then the ordinary assumption that moral behavior flows from moral character is hard to sustain. Gilbert Harman and John Doris have argued that the social-psychological evidence supports a situationist moral psychology in which cross-situational consistency of character is largely illusory. Defenders of virtue ethics respond that the situationist reading overstates the power of situations and understates the role of reflective, trait-governed deliberation. The debate is live, and the group-dynamics experiments are its principal empirical battleground — which is why the methodological soundness of those experiments (especially the Stanford Prison Experiment, whose evidential status is contested) is not a merely historical concern but bears directly on the philosophy of character.

A second philosophical concern is moral responsibility under authority. If the agentic state is genuine — if obedience genuinely involves a transfer of the sense of responsibility from the actor to the authority — then the standard framework for attributing moral and legal blame, which presupposes that the actor is the locus of responsibility, is placed under pressure. The Nuremberg defense ("I was following orders") is the limit case. Milgram's data suggest that the defense is not merely cynical but tracks a real psychological state, which does not excuse the behavior but complicates the architecture of culpability. The group-dynamics literature thus reaches from the laboratory into the foundations of ethics, law, and political theory.

Bibliography Master

1. Asch, S. E. — "Studies of independence and conformity: A minority of one against a unanimous majority", Psychological Monographs: General and Applied 70 (9), 1–70 (1956).

2. Milgram, S. — Obedience to Authority: An Experimental View (Harper & Row, 1974).

3. Milgram, S. — "Behavioral study of obedience", Journal of Abnormal and Social Psychology 67 (4), 371–378 (1963).

4. Janis, I. L. — Victims of Groupthink: A Psychological Study of Foreign-Policy Decisions and Fiascoes (Houghton Mifflin, 1972).

5. Janis, I. L. — Groupthink: Psychological Studies of Policy Decisions and Fiascoes (Houghton Mifflin, 2nd ed., 1982).

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8. Ringelmann, M. — "Notes sur quelques problèmes de la vie industrielle" (1913); discussed in Kravitz, D. A. & Martin, B. — "Ringelmann rediscovered: The original article", Journal of Personality and Social Psychology 50 (5), 936–941 (1986).

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10. Latané, B. & Darley, J. M. — The Unresponsive Bystander: Why Doesn't He Help? (Appleton-Century-Crofts, 1970).

11. Kelman, H. C. — "Compliance, identification, and internalization: Three processes of attitude change", Journal of Conflict Resolution 2 (1), 51–60 (1958).

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16. Reicher, S. D. & Haslam, S. A. — "Rethinking the psychology of tyranny: The BBC prison study", British Journal of Social Psychology 45 (1), 1–40 (2006).

17. Haslam, S. A. & Reicher, S. D. — "Beyond the banality of evil: Three dynamics of an interactionist social psychology of tyranny", Personality and Social Psychology Bulletin 33 (5), 615–622 (2007).

18. Russell, N. & Nicholson, I. — "Situating Milgram's obedience experiments: A case study in the sociology of social psychology", European Journal of Social Psychology 47 (5), 632–643 (2017).

19. Manning, R., Levine, M. & Collins, A. — "The Kitty Genovese murder and the social psychology of helping: The parable of the 38 witnesses", American Psychologist 62 (6), 555–562 (2007).

20. Reicher, S. D., Spears, R. & Postmes, T. — "A social identity model of deindividuation phenomena", European Review of Social Psychology 6, 161–198 (1995).

21. Tajfel, H. & Turner, J. C. — "An integrative theory of intergroup conflict", in Austin, W. G. & Worchel, S. (eds.), The Social Psychology of Intergroup Relations (Brooks/Cole, 1979), pp. 33–47.

22. Hardin, G. — "The tragedy of the commons", Science 162 (3859), 1243–1248 (1968).

23. Axelrod, R. — The Evolution of Cooperation (Basic Books, 1984).

24. Cottrell, N. B., Wack, D. L., Sekerak, G. J. & Rittle, R. H. — "Social facilitation of dominant responses by the presence of an audience and the mere presence of others", Journal of Personality and Social Psychology 9 (3), 245–250 (1968).

25. Doris, J. M. — Lack of Character: Personality and Moral Behavior (Cambridge University Press, 2002).