Obervation is a passive science, experimentation is an active science.

It is what we know already that often prevents us from learning.

The experimenter who does not know what he is looking for will not understand what he finds.

When we meet a fact which contradicts a prevailing theory, we must accept the fact and abandon the theory, even when the theory is supported by great names and generally accepted.

Man can learn nothing unless he proceeds from the known to the unknown.

The terrain is everything; the germ is nothing.

Art is 'I'; science is 'we'.

A fact in itself is nothing. It is valuable only for the idea attached to it, or for the proof which it furnishes.

Those who do not know the torment of the unknown cannot have the joy of discovery.

Science increases our power in proportion as it lowers our pride.

All the vital mechanisms, varied as they are, have only one object, that of preserving constant the conditions of life in the internal environment.

Finishing a book is just like you took a child out in the back yard and shot it.

The paradox of education is that any man only educated by others is an uneducated man without self-education you cannot be educated one in strict sense of this term.

The roots of the abundant life may seem bitter, but its fruits are sweet.

Eyes as black and as shiny as chips of obsidian stared back into his. They were eyes like black holes, letting nothing out, not even information.

A free press can, of course, be good or bad, but, most certainly without freedom, the press will never be anything but bad.

I’m nauseatingly pro-American. I would have come here from any country. The U.S. is where great things are possible.

Bin Laden was once targeted by President Clinton. President Clinton wanted to kill him but couldn't get him. Of course not, we all know what kind of aim Clinton has.

Natural abilities can almost compensate for the want of every kind of cultivation, but no cultivation of the mind can make up for the want of natural abilities.

Stop eating before you're full.

Speak to your people as to men that must be awakened, either here or in hell.