Where there is shouting, there is no true knowledge. – Leonardo da Vinci

The tree of knowledge is not the tree of life! And yet can we cast out of our spirits all the good or evil poured into them by so many learned generations? Ignorance cannot be learned. – Gerard De Nerval

Knowledge is not simply another commodity. On the contrary. Knowledge is never used up. It increases by diffusion and grows by dispersion. – Daniel J. Boorstin