We are all ready to be savage in some cause. The difference between a good man and a bad one is the choice of the cause.

Science, like life, feeds on its own decay. New facts burst old rules; then newly divined conceptions bind old and new together into a reconciling law.

Pessimism leads to weakness. Optimism leads to power.

Truths emerge from facts, but they dip forward into facts again and add to them; which facts again create or reveal new truth (the word is indifferent) and so on indefinitely. The 'facts' themselves meanwhile are not true. They simply are. Truth is the function of the beliefs that start and terminate among them.

Act in earnest and you will become earnest in all you do.

Mankind's common instinct for reality has always held the world to be essentially a theatre for heroism. In heroism, we feel, life's supreme mystery is hidden. We tolerate no one who has no capacity whatever for it in any direction. On the other hand, no matter what a man's frailties otherwise may be, if he be willing to risk death, and still more if he suffer it heroically, in the service he has chosen, the fact consecrates him forever.

Ninety-nine hundredths or, possibly, nine hundred and ninety-nine thousandths of our activity is purely automatic and habitual, from our rising in the morning to our lying down each night.