I know that I am intelligent, because I know that I know nothing.

If you want a love message to be heard, it has got to be sent out. To keep a lamp burning, we have to keep putting oil in it.

Let us permit nature to have her way. She understands her business better than we do.

I am fond of pigs. Dogs look up to us. Cats look down on us. Pigs treat us as equals.

I'm not as famous as Stephen Hawking, but certainly in the U.S., I have a very high profile for a scientist. It is an awesome responsibility, one that I don't shoulder lightly.