Diversity is essential to happiness and in Utopia there is hardly any. This is a defect in all planned social systems.

The harm that theology has done is not to create cruel impulses, but to give them the sanction of what professes to be lofty ethic, and to confer an apparently sacred character upon practices which have come down from more ignorant and barbarous times.

Dogma demands authority, rather than intelligent thought, as the source of opinion; it requires persecution of heretics and hostility to unbelievers; it asks of its disciples that they should inhibit natural kindliness in favor of systematic hatred.

There was, I think, never any reason to believe in any innate superiority of the male, except his superior muscle.

The opinions that are held with passion are always those for which no good ground exists; indeed the passion is the measure of the holders lack of rational conviction. Opinions in politics and religion are almost always held passionately.

Belief in a Divine mission is one of the many forms of certainty that have afflicted the human race.

Never try to discourage thinking, for you are sure to succeed.