Common sense is that layer of prejudices which we acquire before we are sixteen.

Though our conduct seems so very different from that of the higher animals, the primary instincts are much alike in them and in us.

The scientist is activated by a wonder and awe before the mysterious comprehensibility of the universe which is yet finally beyond his grasp. In its profoundest depths it is inaccessible to man.

Incompetence is the true crisis.

Conviction is a good motive, but a bad judge.

The contemplation of this world beckoned as a liberation (...)The road to this paradise was not as comfortable and alluring as the road to the religious paradise; but it has shown itself reliable, and I have never regretted having chosen it.

I am not an atheist. I do not know if I can define myself as a pantheist. The problem involved is too vast for our limited minds.