I will call no being good who is not what I mean when I apply that epithet to my fellow creatures; and if such a creature can sentence me to hell for not so calling him, to hell I will go .

So long as an opinion is strongly rooted in the feelings, it gains rather than loses in stability by having a preponderating weight of argument against it.

Originality is the one thing which unoriginal minds cannot feel the use of.

If opponents of all important truths do not exist, it is indispensable to imagine them and supply them with the strongest arguments which the most skillful devil's advocate can conjure up.

If two or more instances of the phenomenon under investigation have only one circumstance in common, the circumstance in which alone all the instances agree is the cause (or effect) of the given phenomenon.

It is conceivable that religion may be morally useful without being intellectually sustainable.

The only power deserving the name is that of masses, and of governments while they make themselves the organ of the tendencies and instincts of masses.