1. If someone makes eye contact with you for 60% of a conversation they're bored, 80% and they're attracted to you and 100% of the time then they are threatening you.
2. People are more likely to return a lost wallet, if there is a baby picture found inside of it.
3. The pupil of your eye expands up to 45% when you look at someone you love.
4. The maximum number of close relationships/friendships you can maintain is between 50 and 150.