It wearied Carter to see how solemnly people tried to make earthly reality out of old myths which every step of their boasted science confuted.

Religion is still useful among the herd - that it helps their orderly conduct as nothing else could. The crude human animal is in-eradicably superstitious, and there is every biological reason why they should be.
Take away his Christian god and saints, and he will worship something else...

Contrary to what you may assume, I am not a pessimist but an indifferentist- that is, I don't make the mistake of thinking that the... cosmos... gives a damn one way or the other about the especial wants and ultimate welfare of mosquitoes, rats, lice, dogs, men, horses, pterodactyls, trees, fungi, dodos, or other forms of biological energy.

I am, indeed, an absolute materialist so far as actual belief goes; with not a shred of credence in any form of supernaturalism—religion, spiritualism, transcendentalism, metempsychosis, or immortality.

We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far.

The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents... some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new Dark Age.