rigor

If someone were to propose that the planets go around the sun because all planet matter has a kind of tendency for movement, a kind of motility, let us call it an __omph,_ this theory could explain a number of other phenomena as well. So this is a good theory, is it not? No. It is nowhere near as good as the proposition that the planets move around the sun under the influence of a central force which varies exactly inversely as the square of the distance from the center. The second theory is better because it is so specific; it is so obviously unlikely to be the result of chance. It is so definite that the barest error in the movement can show that it is wrong; but the planets could wobble all over the place, and, according to the first theory, you could say, __ell, that is the funny behavior of the __omph.

Rigor alone is paralytic death, but imagination alone is insanity.

Night is a time of rigor, but also of mercy. There are truths which one can see only when it__ dark

Objectivity cannot be equated with mental blankness; rather, objectivity resides in recognizing your preferences and then subjecting them to especially harsh scrutiny _ and also in a willingness to revise or abandon your theories when the tests fail (as they usually do).

The test of real and vigorous thinking, the thinking which ascertains truths instead of dreaming dreams, is successful application to practice.