Actually everybody is selfish, but we do not admit that we are selfish. Considering the reality, selfish character is good to the society. If everyone is selfish to take care only for themselves, the society will be peaceful and stable. Law will control the stability of society.
But, there is a definition about selfish. You must be selfish to yourself, not to take advantage from other people. If your selfish extends to the category of other people, you are violating the right of other people, either mentally or materially.
As a matter of fact, selfish is a kind of self-protection. You have the right to do so as long as you do not offend law in every respect.
In Tokyo, there are many small side-streets where are full of small shops of different trade, closely connected next to each other. The whole street is very clean and tidy. It is because in every morning each shop will clean the space in front of their own shop. They do not help to clean the neighbor’s area. Such disciplined selfish is good to society.
Every country is selfish. The leader of any country always says: “What I am going to do is for the good of country against other country if they should take advantage from us.” Therefore, selfish is the right of every human if you use it rightfully.