I can never satisfy myself until I can make a mechanical model of a thing. If I can make a mechanical model, I can understand it. As long as I cannot make a mechanical model all the way through I cannot understand.

Science is bound, by the everlasting vow of honour, to face fearlessly every problem which can be fairly presented to it.

If we can't express what we know in the form of numbers, we really don't know much about it.

If you can not measure it, you can not improve it.

To measure is to know.

Let nobody be afraid of true freedom of thought. Let us be free in thought and criticism; but, with freedom, we are bound to come to the conclusion that science is not antagonistic to religion, but a help to it.

Large increases in cost with questionable increases in performance can be tolerated only in race horses and fancy women.