Selfishness

Are we a selfish race?Or are we just trying to overprotect ourselves from any danger that may interfere with our plans?And this protection is really such a bad thing?I know a great deal of people that are cheap,for example.They have money and can afford certain things,but they refuse to take advantage of these small,yet important things,because they don't want to spend their money.But money are for spending!!Is their cheapness,in this case, a sign of selfishness(because,undoubtelly,if they refuse to help themselves, they would definetely refuse to help others)?But,on the other hand,it is said that we live the most important parts of our lives(death and birth)alone.Then why the need to interact with others during the rest of the time?You will all say that interacting,better yet,socializing with others is the main characteristic of the human race.But aren't all these acts based on a bit of a masochistic relation?Because any type of friendship supposes two persons,who might have something in common,but who are nonetheless different and who have to accept each other with all their flaws and qualities and make their relationship work,despite all the things that might separate them.But this very effort is what makes the human race unselfish,because by sacrificing his time and feelings in order to gain a friend,a person shows a real proof of selflesness.