If you know, you tell me, share with me. I will be happy and glad to receive it. If you don't know, then I know something. I can share it with you. Then receive it. If both know then there is no need to talk at all. If both don't know, what is the point of talking ? Discussion is meaningless. These are the only possibilities; either we both don't know ? Then we can go on arguing and argument will not bring any conclusion. That's how man has argued down the ages. Great argumentation , to no end. Or, we both know, then there is no point in saying anything.