Mental slavery is mental death, and every man who has given up his intellectual freedom is the living coffin of his dead soul.

For thousands of years people have been trying to force other people to think their way. Did they succeed? No. Will they succeed? No. Why? Because brute force is not an argument.

The present is the necessary product of all the past, the necessary cause of all the future.

There is no harmony between religion and science. When science was a child, religion sought to strangle it in the cradle. Now that science has attained its youth, and superstition is in its dotage, the trembling, palsied wreck says to the athlete: "Let us be friends."

A miracle is the badge and brand of fraud. ... No intelligent, honest man ever pretended to perform a miracle, and never will.

I do not see how it is possible for an intelligent human being to conclude that the Song of Solomon is the work of God, and that the tragedy of Lear was the work of an uninspired man.

Nothing but truth is immortal.