It is still open to question whether psychology is a natural science, or whether it can be regarded as a science at all.

Never think that you already know all. However highly you are appraised, always have the courage to say to yourself-I am ignorant.

Don't become a mere recorder of facts, but try to penetrate the mystery of their origin.

When the dog is repeatedly teased with the sight of objects inducing salivary secretion from a distance, the reaction of the salivary glands grows weaker and weaker and finally drops to zero.

Science demands from a man all his life. If you had two lives that would not be enough for you. Be passionate in your work and in your searching.

While you are experimenting, do not remain content with the surface of things.

Men are apt to be much more influenced by words than by the actual facts of the surrounding reality

Perfect as the wing of a bird may be, it will never enable the bird to fly if unsupported by the air. Facts are the air of science. Without them a man of science can never rise.

Appetite, craving for food, is a constant and powerful stimulator of the gastric glands.

Perfect as the wing of a bird may be, it will never enable the bird to fly.

School yourself to demureness and patience. Learn to inure yourself to drudgery in science. Learn, compare, collect the facts.

It is certainly true that ‘actions speak louder than words, ’ but words become as monuments to thoughts.

Little Fists, what's wrong?

In my experience, ghosts are made up only of the living, people you know are out there but are forever out of range

Nihilists expend everything and everyone except themselves. They are the indispensable men, without whom the world might try to live almost happily.

I just don't have words to express how proud I am of this race team.

In order to plant the Gospel, we must take risk.

It is not wise to find symbols in everything that one sees. It makes life too full of terrors.

I see love as an evolution of true friendship.

The one who bets the most wins. Cards just break ties.

An accident, a random change, in any delicate mechanism can hardly be expected to improve it. Poking a stick into the machinery of one's watch or one's radio set will seldom make it work better.