Why is A=A?
Suppose I want to identify something. I will say, pointing to something, “is it this?” There are only 2 possibilities – that pointed to thing is the thing or something else i.e. it is not.
That leads to (now that we have two things – the thing picked up and the thing checked against) the concepts of SAME & DIFFERENT, corresponding to the answers YES (that thing is it) or NO (that thing isn’t it) respectively, to the question above.
If they are the same, it is that thing itself (we exclude the possibility of an exactly similar other sample since no two different things i.e. one thing and another thing, can be same in all respects; some parameter about them has to be different, say, time or place of birth or the birth-giver or whatever); if different, it is not that thing.
So, the underlined part above means that if A=B, then B is A itself. If B is A itself, then A=B => A=A.
We all say that a ball is a ball; a shirt is a shirt….etc. which is the “first” meaning of anything. The above (A=A), shows that this “first” meaning, and thereby, conceptually speaking meaning, itself, exists. (That is, there is something like meaning).