The Sun-Paul must consider only one thing: what is the relation of this or that external reaction of the animal to the phenomena of the external world?

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.

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

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

Love is like chickenpox. It's much worse when it comes late.

If you can't appreciate the full worth of my courage, you can't admire my mastery.

If God shall choose I shall love thee but better after death

If we are to be truly free, that freedom will come through cooperation and tolerance with one another.

Man reaches the highest point of lovableness at 12 to 17 - to get it back in a second flowering at the age of 70 to 90.

The thought of the future life with its prerogatives and joys helps to make the trials of the present seem light and transient.

I like Instagram - I love pictures, I just dont take them very often.

I think we need to tell stories that reflect our world.

I can sing better after shooting smack in both arms than after eating too much.

Cats are a tonic, they are a laugh, they are a cuddle, they are at least pretty just about all of the time and beautiful some of the time.