The test of all knowledge is experiment. Experiment is the sole judge of scientific truth.

Thus we can get the correct answer for the probability of partial reflection by imagining (falsely) that all reflection comes from only the front and back surfaces. In this intuitively easy analysis, the 'front surface' and 'back surface' arrows are mathematical constructions that give us the right answer, whereas .... a more accurate representation of what is really going on: partial reflection is the scattering of light by electrons inside the glass.

I couldn't claim that I was smarter than sixty-five other guys--but the average of sixty-five other guys, certainly!

It is not unscientific to make a guess, although many people who are not in science think it is.

Physics is to mathematics what sex is to masturbation.

No! Not for a second! I immediately began to think how this could have happened. And I realized that the clock was old and was always breaking. That the clock probably stopped some time before and the nurse coming in to the room to record the time of death would have looked at the clock and jotted down the time from that. I never made any supernatural connection, not even for a second. I just wanted to figure out how it happened.

Listen, I mean that from my knowledge of the world that I see around me, I think that it is much more likely that the reports of flying saucers are the results of the known irrational characteristics of terrestrial intelligence than of the unknown rational efforts of extra-terrestrial intelligence.