A man may not achieve everything he has dreamed, but he will never achieve anything great without having dreamed it first.

Success plus Self-esteem equals Pretensions.

If you care enough for a result, you will most certainly attain it.

Compared with what we ought to be, we are only half awake. Our fires are damped, our drafts are checked. We are making use of only a small part of our possible mental and physical resources.

Nature in her unfathomable designs had mixed us of clay and flame, of brain and mind, that the two things hang indubitably together and determine each other's being but how or why, no mortal may ever know.

A good hypothesis in science must have other properties than those of the phenomenon it is immediately invoked to explain, otherwise it is not prolific enough.

But it is the bane of psychology to suppose that where results are similar, processes must be the same. Psychologists are too apt to reason as geometers would, if the latter were to say that the diameter of a circle is the same thing as its semi-circumference, because, forsooth, they terminate in the same two points.