Justice is a moral principle described by 4 things:
1) What is banned for one is banned for all
2) What is allowed for one is allowed for all
3) What is mandatory for one is mandatory for all
4) Standard that judges one is a standard that judgeds all
For example, if everyone is allowed to do what makes them happy without destroying happiness of others, then homosexuals are allowed to do what makes them happy without destroying happiness of others. Engaging in homosexual activity doesnt destroy anyone's happiness, therefore it is allowed. Someone might say "it makes me unhappy to see all those homosexuals". However, there is nothing about homosexuality that prevents you from being happy and doing what makes you happy, and your hate is the one preventing homosexuals from being happy. More happiness is destroyed by hating homosexuals than it is gained by you not having to watch them.
