1.
Any act performed with the goal of benefiting another person
2.
The desire to help another person even if it involves a cost to the helper
3.
The case in which people think that everyone else is interpreting a situation in a certain way, when in fact they are not
4.
The finding that the greater the number of bystanders who witness an emergency, the less likely any one of them is to help
5.
Any group with which an individual does not identify
6.
The group with which an individual identifies as a member
7.
The ability to put oneself in the shoes of another person and to experience events and emotions (e.g., joy and sadness) the way that person experiences them
8.
The expectation that helping others will increase the likelihood that they will help us in the future
9.
The idea that behaviors that help a genetic relative are favored by natural selection
