Agreeableness

A core personality trait that includes such dispositional characteristics as being sympathetic,
generous, forgiving, and helpful, and behavioral tendencies toward harmonious social
relations and likeability.

Altruism

A motivation for helping that has the improvement of another’s welfare as its ultimate goal,
with no expectation of any benefits for the helper.

Arousal: cost–reward model

An egoistic theory proposed by Piliavin et al. (1981) that claims that seeing a person in need
leads to the arousal of unpleasant feelings, and observers are motivated to eliminate that
aversive state, often by helping the victim. A cost–reward analysis may lead observers to react
in ways other than offering direct assistance, including indirect help, reinterpretation of the
situation, or fleeing the scene.

Bystander intervention

The phenomenon whereby people intervene to help others in need even if the other is a complete stranger and the intervention puts the helper at risk.

Cost–benefit analysis

A decision-making process that compares the cost of an action or thing against the expected benefit to help determine the best course of action.

Diffusion of responsibility

• When deciding whether to help a person in need, knowing that there are others who could also provide assistance relieves bystanders of some measure of personal responsibility
• reducing the likelihood that bystanders will intervene.

Egoism

A motivation for helping that has the improvement of the helper’s own circumstances as its primary goal.

Empathic concern

• According to Batson’s empathy–altruism hypothesis, observers who empathize with a person in need (that is, put themselves in the shoes of the victim and imagine how that person feels) will experience empathic concern and have an altruistic motivation for helping

Empathy–altruism model

An altruistic theory proposed by Batson (2011) that claims that people who put themselves in the shoes of a victim and imagining how the victim feel will experience empathic concern that evokes an altruistic motivation for helping

Helpfulness

A component of the prosocial personality orientation; describes individuals who have been helpful in the past and, because they believe they can be effective with the help they give, are more likely to be helpful in the future.

Helping

Prosocial acts that typically involve situations in which one person is in need and another provides the necessary assistance to eliminate the other’s need.

Kin selection

According to evolutionary psychology, the favoritism shown for helping our blood relatives, with the goal of increasing the likelihood that some portion of our DNA will be passed on to future generations.

Negative state relief model

An egoistic theory proposed by Cialdini et al. (1982) that claims that people have learned through socialization that helping can serve as a secondary reinforcement that will relieve negative moods such as sadness.

Other-oriented empathy

A component of the prosocial personality orientation; describes individuals who have a strong sense of social responsibility, empathize with and feel emotionally tied to those in need, understand the problems the victim is experiencing, and have a heightened sense of moral obligations to be helpful.

Personal distress

According to Batson’s empathy–altruism hypothesis, observers who take a detached view of a person in need will experience feelings of being “worried” and “upset” and will have an egoistic motivation for helping to relieve that distress.

Pluralistic ignorance

Relying on the actions of others to define an ambiguous need situation and to then erroneously conclude that no help or intervention is necessary.

Prosocial behavior

Social behavior that benefits another person.

Prosocial personality orientation

A measure of individual differences that identifies two sets of personality characteristics (other-oriented empathy, helpfulness) that are highly correlated with prosocial behavior.

Reciprocal altruism

According to evolutionary psychology, a genetic predisposition for people to help those who have previously helped them.

Altruism

A desire to improve the welfare of another person, at a potential cost to the self and without any expectation of reward.

Common-pool resource

A collective product or service that is freely available to all individuals of a society, but is vulnerable to overuse and degradation.

Commons dilemma game

A game in which members of a group must balance their desire for personal gain against the deterioration and possible collapse of a resource.

Cooperation

The coordination of multiple partners toward a common goal will benefit everyone involved.

Decomposed games

A task in which an individual chooses from multiple allocations of resources to distribute between him- or herself and another person.

Empathy

The ability to vicariously experience the emotions of another person.

Free rider problem

A situation in which one or more individuals benefit from a common-pool resource without paying their share of the cost.

Interindividual-intergroup discontinuity

The tendency for relations between groups to be less cooperative than relations between individuals.

Outgroup

A social category or group with which an individual does not identify.

Prisoner’s dilemma

A classic paradox in which two individuals must independently choose between defection (maximizing reward to the self) and cooperation (maximizing reward to the group).

Rational self-interest

The principle that people will make logical decisions based on maximizing their own gains and benefits.

Social identity

A person’s sense of who they are, based on their group membership(s).

Social value orientation (SVO)

An assessment of how an individual prefers to allocate resources between him- or herself and another person.

State of vulnerability

When a person places him or herself in a position in which he or she might be exploited or harmed. This is often done out of trust that others will not exploit the vulnerability.

Ultimatum game

An economic game in which a proposer (Player A) can offer a subset of resources to a responder (Player B), who can then either accept or reject the given proposal.