July 4, 2015 9:45:44 AM
Everyone has, at sometime or other, imagined what it would be like to be invisible. The possibility of being able to observe, and possibly act, when no one else can tell you are doing so is a thrill that, despite its impossibility, has fired imaginations for millennia. We have been able to come to understanding of some previously invisible realms; we still can't see ghosts with any reliability, but microbes are no longer invisible to us. The fascination with things we cannot see is detailed in Invisible: The Dangerous Allure of the Unseen (University of Chicago Press) by science writer Philip Ball. He has a huge topic, which he treats mostly chronologically, with impressive detail and a good deal of humor. Invisibility, from legends to camouflage to Hollywood to current technological tricks, is all here.
The first pages have to do with the moral challenge of invisibility: "If you could be invisible, what would you do? The chances are that it will have something to do with power, wealth or sex. Perhaps all three, given the opportunity." Even way back in Plato's Republic the moral problem of this imaginary power was considered. The discussants address the story of Gyges, who got a ring of invisibility and went to town with it, taking over a kingdom and the former king's wife. Plato acknowledged that this is exactly the way anyone would be expected to behave; none of us would be up to the task of staying moral if we could select invisibility. Tolkien had a ring of invisibility in The Lord of the Rings which is far more famous now than the ring of Gyges, but it, too, is inescapably linked to the user becoming greedy and malevolent. A cloak of invisibility is used by an old soldier in the Grimm's fairy tale "Twelve Dancing Princesses." He uses it to spy on the girls and discovers that they are dancing (euphemism?) with a dozen princes. Harry Potter had a cloak of invisibility, to be sure; he is more a literary hero than realistic adolescent if he never used it to check out the girl's shower room. The invisible man in the H. G. Wells story used chemistry rather than magic to become invisible, and insanity ensued. Wells wrote the story in 1897, and he intended to show that the insanity that envelops the scientist who invented the invisibility serum came from his invisibility itself. He was distressed when Universal Studios changed the message to one more typical for horror pictures when they filmed it for the 1933 release. In the movie, the character (in good mad scientist fashion) is driven crazy as a direct side effect of the serum itself.
Turning invisible was such a desirable skill that procuring it was included in every good grimoire. A recipe from 1522 started, "Take a black cat, and a new pot, a mirror, a lighter, coal and tinder," and goes on to explain in detail how to use these items (poor cat) until you get a particular bone that will render you invisible. These recipes depended on rare ingredients or complex procedures, so there were many ways for those who tried them to explain to themselves why the intricacies didn't work. The occult formulas (and Ball reminds us that "occult" originally meant simply "hidden") sometimes called upon demons to confer invisibility. During the Renaissance, understanding magic meant understanding natural magic, and anyone could realize that there were invisible forces at work in nature. The stars and planets, for instance, exerted their occult forces on human affairs, and the lodestone drew iron. To understand such natural magic was simply to try to understand the way the world worked. Ball writes, "Mastery of the occult framework of natural magic was nothing more than a question of acquiring a deep understanding of nature: the objective today claimed by science."
Much of Invisible involves a push and pull between legends and magic on the one hand and science on the other, and Ball shows how ancient dreams of invisibility inform scientific efforts to investigate it, just as science has built on other fantasies about time travel, space travel, or immortality. A most interesting section of the book deals with the spiritualists who insisted that they were doing a scientific investigation of the invisible realm to which the dead had passed, and who from time to time got scientists to investigate and to ally with them. The chemist and physicist William Crookes was among the many nineteenth century scientists who believed that spiritualists were investigating a branch of reality. He was amazed that psychics and mediums could do the demonstrations he enjoyed witnessing, writing of one, "At first we had rough manifestations, the table floated six inches from the ground and then dashed down, loud and unpleasant noises bawling in our ears." Crookes knew that spiritualists were not above using trickery, but he could not see it himself; his lack of skepticism led his to become infatuated with a female teenage medium, who was eventually unmasked. Crookes was no fool, or at least he was not one when he confined himself to physics and chemistry. His investigation of psychics would lead him to invent the "light mill" or radiometer, and he would go on to invent the cathode ray tube, which would later be installed into television sets that pulled images out of invisible waves. Over and over Ball reminds us of how science and magic are intertwined; Edison and Marconi, for instance, both thought their inventions might somehow enable us to communicate with the dead. Edison was "The Wizard of Menlo Park," and during the fad for X-rays (another fascinating invisible power), a weekly magazine called Wilhelm Roentgen a "Wizard of To-day." That these wizards worked usefully with mysterious invisible forces made many think that there was an unseen ghost world, and it was not a fringe idea to believe that such a world might by scientific means be made visible.
Ball explains that we think that we can see the world and universe around us, but we are fooling ourselves. Gradually we have learned that there are unseen energies that flow all around us and unseen microorganisms that work to our advantage or disadvantage (although we can now build devices to detect them). Even our gadgets do not allow us to see what is really going on, though. Take into account the relatively new concepts of dark energy and dark matter, and the universe is overwhelmingly dark, leaving just five percent of all energy and matter that we can actually see. And then there are the "bubble universes" that might be out there entirely separate and inaccessible from our own. And then there may be invisible universes that are right here with us but are confined to inaccessible dimensions and size so that we can only theorize about, not observe, them. To contemplate all these invisibilities is to realize how we are swimming in a sea of ignorance, and how little even Carl Sagan's candle in the dark can avail us.
After a tour of invisibility that takes in the fright wig used on the stage by David Garrick (seeing Hamlet's father's ghost), the dazzle stripes used to make ships look unshiplike, Rosicrucianism, stage magic, spirit photography, and much more, Ball's final chapter takes us to what we really want to, well, not see: the real cloak of invisibility. There are scientific efforts that are trying to make effective what is theoretically possible by fooling around with such things as light's refractive index (best seen in objects appearing bent when put into water). It ought to be possible to bend light waves and then bend them back, so that they emerge on their original trajectory without being blocked by the cloaked object. So far, only cloaking from microwaves, in two dimensions, has been done, so we are pretty far from a cloak of invisibility. Maybe we will get there someday, and we will have to worry realistically about how invisible humans will behave, as Plato theorized long ago.