Parity

There is very unique thing about nature which exists which we dont realize too often. But there are times in our life when we do realize that parity law does exist in nature. That, the things are symmetric in nature. They apply on right-handed and left-handed equally. But very little often do we realize that this parity law is violated nature too! In week interactions there are instances when parity does not hold and there nature stands stripped of its parity! They have different outcomes for up-spins and down-spins. Although nature is strictly fair for strong interactions like gravity, electromagnetic forces and strong nuclear forces.

Feynman effect. :P