Social proof is also known as informational social influence. It is a psychological phenomenon that occurs in ambiguous social situations when people are unable to determine the appropriate mode of behavior. Making the assumption that surrounding people possess more knowledge about the situation, they will deem the behavior of others as appropriate or better informed.

When you are in a random social situation and you begin classifying people based on their current social situation you are supporting the theory of social proof. A man who is surrounded by beautiful women is perceived to be more valuable than a man who is seen being rejected by women.

We tend to make assumptions on the fly that affect our decisions about others. Sometimes we are right and sometimes we are wrong, either way, we're guilty of doing it and it shapes our perception of others. When you are in a theatre and someone claps, everyone else joins in because hearing that first person clap is a psychological trigger that lets us know it's good and deserving of our clapping.

When you consider the strong power of social proof you will begin to see the great value of social proof as a selling tool. When a prospect views your product as a highly desired product they feel a stronger urge to purchase it in order to have something highly coveted. If you promote products as if you are doing the customer a favor by letting them buy your product they will value it more and they are more willing to commit to buying from you.

Social proof is a helpful tool in sales, however, it's power has the potential to be used unethically and therefore should be used with great care. Remember that at the end of the day, it is your reputation as a salesman that is really important.