Freedom of thought is best promoted by the gradual illumination of men's minds which follows from the advance of science.

It stands to the everlasting credit of science that by acting on the human mind it has overcome man's insecurity before himself and before nature.

Science is a wonderful thing if one does not have to earn one's living at it.

But science can only be created by those who are thoroughly imbued with the aspiration toward truth and understanding

The man of science is a poor philosopher.

To raise new questions, new possibilities, to regard old problems from a new angle, requires creative imagination and marks real advance in science.