Man can learn nothing unless he proceeds from the known to the unknown.

The first requirement in using statistics is that the facts treated shall be reduced to comparable units.

The minds that rise and become really great are never self-satisfied, but still continue to strive.

A discovery is generally an unforeseen relation not included in theory.

Put off your imagination, as you put off your overcoat, when you enter the laboratory. Put it on again, as you put on your overcoat, when you leave.

Even mistaken hypotheses and theories are of use in leading to discoveries. This remark is true in all the sciences. The alchemists founded chemistry by pursuing chimerical problems and theories which are false. In physical science, which is more advanced than biology, we might still cite men of science who make great discoveries by relying on false theories.

In the philosophic sense, observation shows and experiment teaches.