Optics & Vision

Why has not man a microscopic eye?
For this plain reason, Man is not a Fly.
Say, what the use, were finer optics giv'n,
T' inspect a mite, not comprehend the heav'n?

Contemporary with Vitellio and Peccam was... Roger Bacon, a man of almost universal genius, and who wrote on almost every branch of science. He frequently quotes Alhazen on the subject of optics, and seems to have carefully studied his writings, as well as those of other Arabians, which were the fountains of natural knowledge in those days, and which had been introduced into Europe by means of the Moors in Spain. Notwithstanding the pains this great man took with the subject of opticks, it does not appear that, with respect to theory, he made any considerable advance upon what Alhazen had done before him.

Not so many years ago this was a mistake that brain scientists actually made: they succumbed all too often to the temptation to treat vision as if it were television — as if it were simply a matter of getting "the picture" from the eyes to the screen somewhere in the middle where it could be handsomely reproduced so that the phenomena of appreciation and analysis could then get underway. Today we realize that the analysis — the whatever you want to call it that composes, in the end, all the visual understanding — begins right away, on the retina; if you postpone consideration of it, you misdescribe how vision works.