Light travels faster than sound, which is why most people appear brilliant until you hear them.

He who feels he is too small to make a difference has never been bitten by a mosquito.

 The wise old owl sat on an oak,
The more he saw, the less he spoke;
The less he spoke, the more he heard;
Why aren't we all like that wise old bird?
~ Edward H. Richards

Why are wise men and wise guys the exact opposite?

You can't have everything. Where would you put it?