It is a very simple law. It states that contradictory statements cannot both be true in the same sense, e.g. the two propositions “A is B” and “A is not B” are mutually exclusive.
But it is amazing how hard it is to apply in practice. Because we contradict ourselves every living moment. Our decisions are totally contradictory to our thoughts. The logical propositions assume a logical structure to everything. But the human mind is so far removed from it. Unless it is a trained mind, it is full of contradictions and doubt. The path to success in anything you want is always simple- very logical. Contradictions, and exceptions in the mind kill that beauty of simplicity.
If you do manage to remove contradictions from your thought process though- if logic can be your only guide, you will conquer all. I struggle with it every day – “A is B” and “A is not B” are mutually exclusive. Non-contradiction.