A REAL UNSUNG HERO
from COSMOS, pp. 180-181
[Open quote] Democritus may have come from Abdera, but he was no dummy. He believed that a large number of worlds had formed spontaneously out of diffuse matter in space, evolved and then decayed. At a time when no one knew about impact craters, Democritus thought that worlds on occasion collide; he believed that some worlds wandered alone through the darkness of space while others were accompanied by several suns and moons; that some worlds were inhabited, while others had no plants or animals or even water; that the simplest forms of life arose from a kind of primeval ooze. He taught that perception—the reason, say, I think there is a pen in my hand—was a purely physical and mechanistic process; that thinking and feeling were attributes of matter put together in a sufficiently fine and complex way and not due to some spirit infused into matter by the gods.
Democritus invented the word atom, Greek for "unable to be cut." Atoms were the ultimate particles, forever frustrating our attempts to break them into smaller pieces. Everything, he said, is a collection of atoms, intricately assembled. Even we. "Nothing exists," he said, "but atoms and the void."
When we cut an apple, the knife must pass through empty spaces between the atoms, Democritus argued. If there were not such empty spaces, no void, the knife would encounter the impenetrable atoms, and the apple could not be cut. Having cut a slice from a cone, say, let us compare the cross sections of the two pieces. Are the exposed areas equal? No, said Democritus. The slope of the cone forces one side of the slice to have a slightly smaller cross section than the other. If the two areas were exactly equal, we would have a cylinder, not a cone. No matter how sharp the knife, the two pieces have unequal cross sections Why? Because, on the scale of the very small, matter exhibits some irreducible roughness. This fine scale of roughness Democritus identified with the world of the atoms. His arguments were not those we use today, but they were subtle and elegant, derived from everyday life. And his conclusions were fundamentally correct.
In a related exercise, Democritus imagined calculating the volume of a cone or a pyramid by a very large number of extremely small stacked plates tapering in size from the base to the apex. He had stated the problem that, in mathematics, is called the theory of limits. He was knocking at the door of the differential and integral calculus, that fundamental tool for understanding the world that was not, so far as we know from written records, in fact discovered until the time of Isaac Newton. Perhaps if Democritus' work had not been almost completely destroyed, there would have been calculus by the time of Christ.
Thomas Wright marveled in 1750 that Democritus had believed the Milky Way to be composed mainly of unresolved stars: "long before astronomy reaped any benefit from the improved sciences of optics; [Democritus] saw, as we may say, through the eye of reason, full as far into infinity as the most able astronomers in more advantageous times have done since." Beyond the Milk of Hera, past the Backbone of Night, the mind of Democritus soared.
As a person, Democritus seems to have been somewhat unusual. Women, children and sex discomfited him, in part because they took time away from thinking. But he valued friendship, held cheerfulness to be the goal of life and devoted a major philosophical inquiry to the origin and nature of enthusiasm. He journeyed to Athens to visit Socrates and then found himself too shy to introduce himself. He was a close friend of Hippocrates. He was awed by the beauty and elegance of the physical world. He felt that poverty in a democracy was preferable to wealth in a tyranny. He believed that the prevailing religions of his time were evil and that neither immortal souls nor immortal gods exist: "Nothing exists, but atoms and the void."
There is no record of Democritus having been persecuted for his opinions—but then, he came from Abdera. However, in his time the brief tradition of tolerance for unconventional views began to erode and then to shatter. People came to be punished for having unusual ideas. A portrait of Democritus is now on the Greek hundred-drachma bill. But his insights were suppressed, and his influence on history made minor. The mystics were beginning to win. [Close quote]
How can we not admire this individual who came to so many conclusions all those many years ago which have proven true with the advances of scientific measurement? Amazing too to think that at one time in the history of humankind, only one (perhaps) person held these thoughts in his head and, now, so many more of us now hold them in our heads. Think also how Democritus's mind functions well beyond our modern fundamentalist's mind which still reckons the world to be but 6000 years old! Just stop, now, and think of it, how marvelous it is!
"The first step to knowledge is to know that we are ignorant." —Lord David Cecil [Who?]