This sense of power is the highest and best of pleasures when the belief on which it is founded is a true belief, and has been fairly earned by investigation.

There is one thing in the world more wicked than the desire to command, and that is the will to obey.

scientific thought does not mean thought about scientific subjects with long names. There are no scientific subjects. The subject of science is the human universe; that is to say, everything that is, or has been, or may be related to man.

No simplicity of mind, no obscurity of station, can escape the universal duty of questioning all that we believe.

A little reflection will show us that every belief, even the simplest and most fundamental, goes beyond experience when regarded as a guide to our actions.

If I steal money from any person, there may be no harm done from the mere transfer of possession; he may not feel the loss, or it may prevent him from using the money badly. But I cannot help doing this great wrong towards Man, that I make myself dishonest.

When an action is once done, it is right or wrong for ever; no accidental failure of its good or evil fruits can possibly alter that.