If I am ever obscure in my expressions, do not fancy that therefore I am deep. If I were really deep, all the world would understand, though they might not appreciate. The perfectly popular style is the perfectly scientific one. To me an obscurity is a reason for suspecting a fallacy.

Do today's duty, fight to-day's temptation; and do not weaken and distract yourself by looking forward to things which you cannot see, and could not understand if you saw them.

Nature's deepest laws, her only true laws, are her invisible ones.

A blessed thing it is for any man or woman to have a friend, one human soul whom we can trust utterly, who knows the best and worst of us, and who loves us in spite of all our faults.

Mathematical knowledge is not-as all Cambridge men are surely aware-the result of any special gift. It is merely the development of those conceptions of form and number which every human being possesses; and any person of average intellect can make himself a fair mathematician if he will only pay continuous attention; in plain English, think enough about the subject.

There are two freedoms - the false, where a man is free to do what he likes; the true, where he is free to do what he ought.

Do noble things, not dream them all day long.