Agnosticism simply means that a man shall not say he knows or believes that for which he has no grounds for professing to believe.

Every great advance in natural knowledge has involved the absolute rejection of authority.

God give me strength to face a fact though it slay me.

I have no faith, very little hope, and as much charity as I can afford.

If a little knowledge is dangerous, where is the man who has so much as to be out of danger.

Irrationally held truths may be more harmful than reasoned errors.

It is an error to imagine that evolution signifies a constant tendency to increased perfection. That process undoubtedly involves a constant remodelling of the organism in adapt ...

Make up your mind to act decidedly and take the consequences. No good is ever done in this world by hesitation.

Only one absolute certainty is possible to man, namely that at any given moment the feeling which he has exists.

Science warns me to be careful how I adopt a view which jumps with my preconceptions, and to require stronger evidence for such belief than for one to which I was previously hos ...