Every period ruled by mystics was an era of stagnation and want, when most men were on strike against existence.

Reason is not automatic. Those who deny it cannot be conquered by it. Do not count on them. Leave them alone.

What objectivity and the study of philosophy requires is not an 'open mind,' but an active mind - a mind able and eagerly willing to examine ideas, but to examine them criticially.

The right to life is the source of all rights -- and the right to property is their only implementation. Without property rights, no other rights are possible. Since man has to sustain his life by his own effort, the man who has no right to the product of his effort has no means to sustain his life. The man who produces while others dispose of his product, is a slave.

Every man builds his world in his own image. He has the power to choose, but no power to escape the necessity of choice.

Face a challenge and find joy in the capacity to meet it.

No matter how vast your knowledge or how modest, it is your own mind that has to acquire it. It is only with your own knowledge that you can deal. It is only your own knowledge that you can claim to possess or ask others to consider. Your mind is your only judge of truth - and if others dissent from your verdict, reality is the court of final appeal. Nothing but a man's mind can perform that complex, delicate, crucial process of identification which is thinking. Nothing can direct the process but his own judgment. Nothing can direct his judgment but his moral integrity.