CHAPTER ONE -- 1.1 & 1.2
The Matter of Metaphysics Our corporeal bodies appear to be made of flesh and bone, blood and bile, tooth and nail. Yet the stuff of which we are made all seems to grow from what we eat, and that from soil, water, and sun all stirred by the wind. How does that happen? The material world seems so vast and varied, how did we ever come to know the nature of its particulars? From time to time since the beginning of human culture, wisened elders, visionaries, and pretentious youths have stepped forward with explanations. In their telling of how we came to know it, some say it all began with gossamer, or gods, while others offer a stouter material as mechanism for explanation. The long winding story of human knowledge about materiality has no obvious beginning, no firm conclusion even today, and thousands of worthy details along the way. The following version of the tale begins with a quick survey of materials known to our ancestors, followed by a glimpse of several of their efforts to explain the nature of materiality. Many important moments of human ingenuity and thoughtful insight are here excluded for sake of moving the story forward, eventually toward our current concept of atom and molecule.
Figure 1.1
"Evidence from genetics and archaeology places the origin of modern humans (Homo sapiens) in Africa roughly 200,000 years ago. The first moderns to leave the continent set off around 60,000 years ago. This map shows first migratory routes taken by humans, based on surveys of different types of the male Y chromosome."
(Map and quote from 13APR05 BBC News science article about "research based on DNA testing of 100,000 people from indigenous populations around the world." Source: The Genographic Project.)
1.1 Experiencing the Material World The story of material discovery began as the primate ancestors of our human species came down from the trees. Nature's bounty of botanical and biological materials lined the path along which our primate progenitors nibbled their way across Africa. They ate plants and animals as hunger demanded. They breathed air every second, walked upon the sand and soil by the hour, and drank many times a day. Air, earth, and water were always materials of prime importance. Wind, rain, lightning, sun, moon, and stars were constant sources of wonder. While lightning gave fire freely, many tens of thousands of years passed before the descendants discovered the means to control fire, developed their capacity for language, and ate their way into other continents. Stone, bone, and wood for tools, sinew for binding, fiber and hide for wraps, and salt (sodium chloride) and herbs for the seasoning of food were among the more easily accessible materials. As hunters and gatherers, our ancestors eventually came to use clay (silicates) for utensils, colorful materials for decoration, urine (uric acid) and oak bark (tannic acid) for the preparation of hides, and willow bark (salicylic acid) for medicine. While such list is sketchy, it does suggest that our species has always been engaged with a wide variety of materials. Some 10-20,000 years ago, the seeds of plants were discovered to contain somehow in their material the virtue of fecundity. Tending the seeds to manifest harvest of grains, our ancestors developed a culture grounded by practical knowledge of flora, season and soil. Civilization arose through the bounty of agriculture since less time feeding the face meant more time-- to organize projects, to use earth and wood to build, to ponder and interact with new materials. Grains as well as fruit yielded wine and beer (ethanol). Herbs, vegetable oils, and animal fats were used to prepare a variety of nostrums, unguents and analgesics. Mineral pigments were variously isolated for use in glazes and paints, including red cinnabar (mercury sulfide), red and yellow earths (iron oxides), brown earth (manganese oxide), and a blue mineral (cobalt, copper oxides). The non-reactive metals (their atoms avoiding unlike atoms)-- silver, gold, and copper-- were at first discovered in readily visible deposits and as rocks were heated by fire until the molten substance ran off. Obtained so easily, such metals proved useful in implements and ornaments. Centuries later, a more intense heat (eventually generated by mechanical bellows) allowed the purification of the reactive metals from mineral ores to yield tin, iron, and lead. Millennia later, mercury and sulfur were employed by alchemists in crude 'experiments'. Potash (potassium), caustic lime (calcium oxide), soda (sodium hydroxide), soda ash (sodium carbonate) and a variety of useful substances eventually classified as acids and salts were isolated and employed for practical purposes. Saltpeter (potassium nitrate), sulfur and charcoal (carbon) were combined to make gunpowder. While of little practical use, lodestones (magnetic iron), quartz (crystalline atomic arrays refracting photons), and luminesence (from strange organisms, the phosphorescent sea, and an occasional meteor stone) surfaced perennially to inspire curiosity. Down through the ages until the late 19th century, people across the face of the earth used a variety of materials without a comprehensive theory of the atomic elements and their compounds. They simply learned what worked and what didn't in specific situations, then handed their knowledge down through recipes. And all the while, efforts were made by some to see into the deeper nature of things.
Figure 1.2
1.2 Explaining the Material Substrate
Living in small tribes through the seasons of the hunt for edible flora and fauna some 50-100,000 years ago, our early ancestors probably engaged in story-telling. Now and then a dreamer no doubt shared a vision of creation sufficiently memorable to establish a tradition. Whether born of sleep in a dream or extraordinary neural stimulation by an ingested substance, the story founder may have explained the origin of everything. We might imagine a mythopoeic person who perceived that the ancestors of rock and tree and cloud and beast and star and river were hatched altogether from an egg given by that prolific flying creature, the brightly colored wikiba. Perhaps the vision was granted by the spirit of the wikiba. As the story was told and retold around the fire in cave or crude dwelling during the generations after, who was to say it was not so?
Different stories arose in disparate tribes and grew into divergent mythos over the centuries. In those regions of the world with resources sufficient to support a larger population, tribes competed for territory both geographic and ideomythic. In several places around the globe, native ideas enabled the domestication of animal and plant which in turn required grazing lands, bounded fields, and livestock pens as well as fixed settlements for the agriculturalists. Both in terms of empirical practice and metabolic utility, the germination of primitive agriscience enabled the cultivating tribe to grow into a supertribe. Coastal communities meanwhile developed hook, line, net, and boat to harvest the bounty of the seas.
Expanding from the fertile crescent to the east of the Mediterranean Sea approximately 10,000 years ago, an incipient agricultural civilization sowed seed east and west. Harvest led to greater harvest, disseminating method and food supply for those humans born to it as well as neighbors converted to botanical dedication. As fattening tribes rubbed against bordering tribes in need of more land for tillage and housing, often spurred by war or trade, cultural differences became fractious or blended according to circumstance. Supertribes formed, merging villages into cities. As populations mixed, a mythos rooted in one tribe or visionary was confronted by an unrelated mythos from another sacrosanct source. Time and again, the obvious question arose: what makes your story better than mine? Among those who were naturally inclined to have visions and/or tell stories, some eventually realized the dilemma presented by competing creation myths: if we all live in the same world, then we should have the same explanation of how it came to be. While force of arms might establish the precedence of the victor's myth in the more malleable minds subject to it, the more discriminating thinkers slowly developed the arts of debate and reasoning in their struggle to provide an acceptable common story. The move away from myth towards a more reasoned explanation of how things came to be was, of course, gradual over the millenia-- and is still not complete in our own 21st century CE (Common Era, defined by the first year of the Christian calendar, which they call 1 Anno Domini).
For an account of the ebb and flow of ideas across the fertile crescent, including China, India, Mesopotamia, Egypt, and Greece in its tide during the latter millenia of the ancient world, see The Shape of Ancient Thought (McEvilley, 2002). For a map of the ancient world with reference to early scientific thought, visit the physics.org website
With all due respect to the other tribes of the region and around the world, we focus here on several descendants of the Greek tribes which swarmed towards the region of agricultural fecundity. The Achaean, Aeolian, Ionian, and Dorian tribes moved in successive waves southwesterly across the Balkans and down into the lands around the Aegean Sea in the third and second millenia BCE. These tribes developed a hardscrabble lifestyle as they settled in the rocky valleys and coastal beachheads of the mountainous terrain of what is now modern Greece. The last wave, the Dorians, displaced the Ionians who subsequently settled along the western coast of Turkey.
The Greeks were an adventurous and oft aggressive people who, having gained seafaring skills from native Aegean populations during the second millenium BCE, expanded their culture throughout the Aegean's numerous islands. They developed a culture of trade which gradually spread their influence throughout the Mediterranean world and across the fertile crescent. By the first millenium BCE, many of the Greek tribes had developed supertribal polities which came to be known as city-states, each governed locally by autocrat, oligarchy, or more rarely an elected assembly. The city-states formed leagues and alliances for the sake of trade as well as wars of defense and offense. Separately and in alliance, they established successful Mediterranean colonies near and far, always in tension with native populations. Most importantly for our story, the city-states fostered the arts and education which enabled certain of their citizens to develop a philosophical mode of thought.
The most remarkable Greek philosophers thrived during the 6th through the 4th centuries BCE in lands around, as well as the islands of, the Aegean and Mediterranean Seas. As discussed below, these theorists are significant in that theirs is the thread of thought which winds through the Mediterranean and European cultures that roundabout fostered modern atomic theory. As we glimpse something of their ancient thought, it will be helpful to remember that we citizens of the 21st century can hardly imagine a way of life before the silicon chip, electronic transistor, vacuum tube, or electricity-- much less before the printing press and a widespread dissemination of information. Without benefit of such fruits of science and technology, the brains of the ancients were nevertheless equipped as ours, genetically, and the theorists discussed below were often enough brighter than many educated folk today. Yet they were starting their discourse on the nature of matter from scratch, at best, or mythology at least. Indeed, none of the thinkers discussed below neglected to pay homage to the divine, and all were imbued with the spirit of Homer and Hesiod as it wafted down from the 8th century BCE to infuse with verse the minds of men in need of insight from the gods.
Besides the obvious historical distance between the ancients and our selves, each of us as human whether ancient or modern is born from a culture embued with particular religious and mythical currents of understanding. Even if we swim against the currents, few of us have escaped the need to link an explanation of the nature of material substance with the questions of its origin and purpose. Who has the strength to pull back curiosity after the first questions: "Of what is the cosmos made, and how?" We also need to know: "Why?" Twentieth century physicists explained material substance through atoms with origins in the Big Bang but avoided the question of purpose. The ancients tried a variety of approaches, a few of which are sampled below. To keep the story brief, we'll speak more of the "what?" and less of the "how and why?"