Why Parents Think Their Children Are So Smart

I would guess that it has something to do with the fact that when they first met their children, the ability to support one's own head was considered a milestone far off in the future. The child came into the world being able to do basically 2 or 3 things. Think of it as being that any positive number is infinitely greater than 0.

Now, I have no explanation for why parents think their own children are the most beautiful children in the world, because I have seen some pretty not-beautiful babies and children. Such a thing can only be explained as a feeling/thought that is divinely placed ;)

Does anyone have better theories?