Leonardo da Vinci

He who is fixed to a star does not change his mind.

The greatest deception men suffer is from their own opinions.

Learning never exhausts the mind.

You cannot give up on the American dream. We cannot allow our fears and our disappointments to lead us into silence and into inaction.

By use you possess gain; by disuse you decline and lose.

Bacteria mineralized the rocks; they deposited the iron. They made the geology we see.