If you want your children to be intelligent, read them fairy tales. If you want them to be more intelligent, read them more fairy tales.
Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.
Black holes are where God divided by zero.
Never memorize something that you can look up.
A man should look for what is, and not for what he thinks should be.
Everything should be made as simple as possible, but not simpler.