The phenomena of judging a person the moment you meet them is called “thin slicing” and scientist say humans do it with every single interaction they make throughout the day—most of the time unknowingly. According to research conducted by multiple universities and highlighted by an article on MSN news, here are three things we decide about a person within seconds of meeting them.

Intelligence: eye contact is a huge factor in being perceived as intelligent. If you make and keep eye contact during a conversation, you are more likely to come off as smart in the eyes of the person doing judging.

Success: people decide whether you are successful or not based on the fit of your clothes. MSN referenced a study that found people with tailed suits were perceived as more successful than those with off-the-rack attire.

Trustworthiness: a University of Princeton study found that people decide whether or not someone is trustworthy within milliseconds of meeting them. The study does not speculate as to the reason why, only that people make snap judgments.