For Geeks Ony!!!!
The latest on science, from 1690
For geeks only….You’ve been WARNED!
Geeks out there know that light, something that has been researched to death by physicists, is still something of an enigma. No, we don’t know for sure what it is. It shows characteristics of being a particle (particle or quanta theory) and a wave (wave theory). Neither theory fully defines light as we know it.
Below is a “translation” of an article in the Athenian Mercury of Jan 18, 1690. This is during the heyday of arguably the greatest physicist of all time, Sir Issac Newton. Having studied more physics than I can even remember, both in high school and college, I thought I knew a few things. But I had always assumed that particle theory was a relatively new idea. Nope, that theory goes back to Newton’s time, as well as wave theory. Sill, as ‘scientific’ as Newton was, many scholars of the time were what we might call philosopher scientists. Lacking the research facilities that we now have, they tried to think their way through to their conclusions. This is a bit similar to the ancient Greek scholars who managed to envision the idea of atoms and elements based solely on reason, with no research. Even today, science that ventures beyond the ability to measure is as much philosophy as it is science. Who knows how they’ll look upon us in several centuries. Be careful what you post on the internet, folks. It will probably still be there in three centuries, and you might be the butt of some pretty funny jokes!
Here is my ‘translation’, with italicized comments from me. It starts with a question, which is part of the original text. It’s a tough read, for sure. They had no problem with run-on sentences, back in the day:
Question: Whether light hath any corporeity (physical existence)? If it hath, why does it so pierce the air and even hard and diaphanous bodies, as we see that it doth. If it has not (physical existence), how can it be sensed, since it often affects the eye with offense.
Answer: That light is a real body, or which is the same, that the particles (now known as photons) which strike the eye in such a manner as to produce such a sensation are corporeal (solid), is now, we think, generally held.: That ‘tis not a quality, an accident, or mere mortification only, seems to be pretty plain from its first original, for it had a peculiar creation; God said let there be light and there was light, which looks too great for an accident, or imperfect, precarious being. But though it be body, it is the most refined part of the body, pure ether (ether is perhaps equivalent to the firmament mentioned in the creation story. I recently found out that ether was still considered a ‘thing’ until the end of the 1800s!), it may be, if we know what that was, nay, the very efflorescence, and (if we might here use the word) spirits, essence, or tincture, or ether, and if Aristotle had made his Quinta Essentia (After the four ‘elements’, earth, air, fire, and water, Aristotle considered the fifth element, to be ether.), he might have come nearer the Truth than making it mere accident. Now the parts of it (photons) must be supposed extremely fine, much finer than the pores of water or air through which it passes (we now know that matter contains more space “between the atoms”, than atoms), which we know not else how it could do; since otherwise those substances would terminate and resist it. And tis the same in all other diaphanous substances, though of never so close of a contexture. The rays of light, the sun beams themselves, which we know are body, because we can contract or dilate them (magnify or disperse?), we are yet as sure, do pass through the pores of glass, unless there’s something fixed on the contrary side, to stop their journey, in which case the are forced to bend back like the sword when a pass is made against any hard substance, and sometimes fly in shivers, as that will do, which if you please you may call reflection and refraction. Day can find us, as well as we see that at a little hole, and it affects the eye with pleasure as well as offense, unless in owls and other birds of night; even through our closed eyelids, and tis we think unaccountable how any thing but a real self-subsisting being (particles) should make such a vivid impression on our senses. There may perhaps be an objection made from that light we fancy we see sometimes in the dark, or when we receive a blow on the eye: but what if this should only be an actual striking fire. The excitation we mean, of some real particle of light, lurking in some of the humors of the eye, which we doubt not do contain a sort of a phosphor, which is extracted by chemists from a liquor of the same substance with our tears; as tis to be seen proceeding from the sweat of horses and other beasts when stroked at night; and we have known it also in men; and the ignes lambens (apparently, phosphorescence. The writers seems to liken phosphoresce to ‘stars in the eyes when we are hit in the face.)which has been seen on several person’s heads, we are apt to think it is no other. However, we have ourselves experience on intense reading, especially by candle light, together with a heat tenderness of the eye, expression of water, a mighty glazing light often returning, and remaining for some time within the organ, which we have sometimes fancied did not so much arise from over-tension of the optic nerve, by which some perhaps would solve it, as from some accidental chemical preparation of nature, like that we have already mentioned. (perhaps ‘afterimages’ — https://www.ceenta.com/news-blog/why-do-i-see-afterimages)
If you made it all the way through, congratulations! Your merit badge for scientific inquisitiveness is in the mail! (But the mail has been slow, lately.)
Comments and suggestions would be welcomed.
Here is a modern take on this discussion. After three centuries we know more, but still can’t exactly answer the question. https://www.britannica.com/science/wave-particle-duality