Learn what is true in order to do what is right.

The improver of natural knowledge absolutely refuses to acknowledge authority, as such. For him, skepticism is the highest of duties; blind faith the one unpardonable sin.

Only a scientific people can survive in a scientific future.

If the perpetual oscillation of nations between anarchy and despotism is to be replaced by the steady march of self-restraining freedom, it will be because men will gradually bring themselves to deal with political, as they now deal with scientific questions.

The only good that I can see in the demonstration of the truth of "Spiritualism" is to furnish an additional argument against suicide. Better live a crossing-sweeper than die and be made to talk twaddle by a "medium" hired at a guinea a séance.

Rome is the one great spiritual organisation which is able to resist and must, as a matter of life and death, the progress of science and modern civilization

The method of scientific investigation is nothing but the expression of the necessary mode of working of the human mind.