Explanation for Karma - Universal self

As you sow so shall you reap" This is the Law of Karma. Interestingly, both science and religion recognize this law. In science it is often stated, “For every action there is an equal and opposing reaction.” Its religious counterparts are, “An eye for an eye, a tooth for a tooth”;; and “As you do unto others, it will be done unto you.” Even today’s common knowledge expresses this principle in the saying, “What goes around, comes around.” This is the law of karma, of cause and effect.

Though most people intutively understand the concept of Karma, there isn't an explanation as such for it. The explanation is that we all have something in common, which is the universal self. When we recognize the universal self in others (as well as in ourselves) and act in their best interests of the whole, we therefore act in our own best interests.