# Influence: Science and Practice

> The principle of authority:

The <principle of authority>:

> People tend to comply when someone with authority makes a request. As discussed in <The Art of Deception>, people often comply when they believe the requester holds authority or has been authorized to make the request.

The <principle of liking>:

> People are more likely to agree to a request when the requester seems likable (good looks, nice clothes, an expensive car, costly accessories, etc.), or shares their interests, beliefs, and attitudes.

The <principle of reciprocation>:

> When we receive something valuable, or a promise of receiving it later, we tend to comply automatically with requests. The gift may be material, advice, or help. When someone does something for you, you feel an urge to repay them. This powerful feeling arises even without a specific request from the person who did you the favor. One of the most effective ways to get someone to do you a favor is to give them a gift or some help. (See <Altruistic punishment>, [Reciprocal altruism](https://wiki.g15e.com/pages/Reciprocal%20altruism.txt).)

The <principle of consistency>:

> People tend to comply when they have made a commitment or taken a position for a cause. Once we promise to do something, we tend to act in accordance with our words and promises because we do not want to appear untrustworthy or undesirable. (See <Cognitive dissonance resolution>, [Self deception](https://wiki.g15e.com/pages/Self%20deception.txt).)

The <principle of social proof>:

> People tend to follow an action when it matches what other people are doing. They see others' behavior as justification that their own behavior is correct and appropriate. (See <Asch conformity experiments>.)

The <principle of scarcity>:

> People tend to comply with requests when they believe that the item they seek is in short supply, that others are competing for it, or that it is available for only a short time.