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.

It has long been known for sure that the sight of tasty food makes a hungry man's mouth water; also lack of appetite has always been regarded as an undesirable phenomenon, from which one might conclude that appetite is essentially linked with the process of digestion.

But man has still another powerful resource: natural science with its strictly objective methods.

Possibilities are like the wings of birds; they allow man to soar and to climb to the heavens. And facts are like the atmosphere against which those wings must beat, and without which the soaring bird will surely plummet back to earth.

Mankind will possess incalculable advantages and extraordinary control over human behavior when the scientific investigator will be able to subject his fellow men to the same external analysis he would employ for any natural object, and when the human mind will contemplate itself not from within but from without.

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