You can tell by the company people choose what sort of character they have

As the saying goes, “Birds of a feather flock together.” We usually choose friends and business associates who like the same things we do, people who share the same values. If you choose happy, positive, productive companions, the odds are that you are or will soon become happy, positive, and productive yourself. Unfortunately, the reverse is also true. Unhappy, negative, destructive people are sure to drag you down with them. Choose to spend most of your time with persons who have PMA — a Positive Mental Attitude. If your job requires you to spend time with negative people, limit that time to the best of your ability and above all don’t let them discourage you with their negativism. Instead, display your own PMA