Time, whose tooth gnaws away everything else, is powerless against truth.

Science has fulfilled her function when she has ascertained and enunciated truth.

The more rapidly truth is spread among mankind the better it will be for them. Only let us be sure that it is the truth.

Ecclesiasticism in science is only unfaithfulness to truth.

The only medicine for suffering, crime, and all other woes of mankind, is wisdom. Teach a man to read and write, and you have put into his hands the great keys of the wisdom box. But it is quite another thing to open the box.