In this blog entry I’d like to discuss some of the ideas that I have been researching so far here at Chemical Heritage Foundation, report on a conference I attended last week, and give an overview of my plans for the next week.
I’ve been conducting my research at CHF for about 2 1/2 weeks. So far I am on schedule for the topics I wish to cover while I’m here in Philadelphia. My goal for these first two weeks was to survey the theories of elements and atoms proposed by the ancient Greek philosophers, then use the third week to research how these theories were carried into the Middle Ages. I used to think that Greek scientific thought on the nature of matter could be divided into a neat dichotomy, with theories of elements (stoicheia) as proposed by Empedocles and Aristotle on one side, and theories of atoms as proposed by Democritus and Epicurus on the other. As I have dug deeper, however, I find that the issue isn’t nearly so simple. Not only did the Greeks theorize about the nature and structure of matter, they also looked at the nature of change, the origin and fate of the universe, and the underlying forces that drive it all. This creates whole sets of conceptual dichotomies. Attempting to sort through all of this while getting to know the personalities and lives of these philosophers has been a fun challenge. I can’t say I’m much of an expert yet, but I have enough to begin to put together a podcast episode on this topic, to be completed and uploaded by the end of August.
At the risk of over-simplifying, here is what I’ve found: the Greeks were already thinking about where the universe came from and what it was made out of by the time of Thales of Miletus, around 585 B.C., who was considered one of the first philosophers (independent thinkers – “lovers of wisdom”). Thales proposed that everything was made of water, although his follower Anaximenes thought it was air. By about 500 B.C., Parmenides of Elea taught that change was an illusion, that the senses weren’t to be trusted, and that there could only be Being and Non-being. He denied the possibility of empty space (a void) saying it was a logical impossibility. His student Zeno, in a series of famous paradoxes, such as the one about Achilles and the Tortoise, showed that motion (and therefore change) was impossible.
In contrast to the Eleatic School, Heraclitus of Ephesus taught that change was the only constant in the universe, that you can’t step in the same river twice because both you and the river have changed in between. He felt that fire, as a symbol of change, was the universal element. As a compromise between the extremes of Parmenides and Heraclitus, Empedocles of Akragas proposed that there were four elements (earth, water, air, and fire) and that although these elements were eternal and changeless, they could combine and break apart to form new materials. He felt that their were two opposing forces, what he called Love and Strife, which tried to bring the elements together or break them apart.
Also in contrast to the Eleatic School, Leucippus of Abdera proposed that all things were made of small, indivisible, unchanging atoms which traveled in a void, combined by the forces of a primordial vortex into larger clumps of matter. His pupil, Democritus, took these ideas further and said that nothing existed except atoms and the void, and that atoms combine from necessity (he was a bit vague on what this meant). Unfortunately, most of his original works (some 70 books) are lost and we know of them only from the references of others.
One of those others was Aristotle, the pupil of Plato and teacher of Alexander the Great. Aristotle tried to create a system of knowledge that tied everything together, including the material world and the heavens, and that explained the nature of change. Like his teacher Plato, he felt that there were ideal forms that created the patterns for all things, and that all things had purpose. He taught that the primordial subtance (hyle) took on the forms (morphe) of the four pure elements, and that these elements had properties including hot and cold and wet and dry. All other materials were mixtures of these elements. By changing the properties of one material, it could be transmuted into another, such as base lead maturing into precious gold. He also felt that the elements were arranged in spherical shells with earth at the center, surrounded by water, then air, then fire. The heavy elements sank because of a force he called gravity and the lighter elements rose through a force called levity. Finally, he proposed that a fifth element (literally the “quintessence”) called ether surrounded fire and was the material from which the incorruptible heavens were made.
Aristotle’s views were brought into harmony with the Catholic Church by the Summa Theologica of St. Thomas Aquinas. Democritus’ views on atoms were supported by Epicurus and therefore seen as too materialist and hedonistic by the church, and they fell out of favor (but never entirely died, as I’m finding out this week). It wasn’t until the Enlightenment that atomic theory began to revive.
Now, of course, this is a very simplistic overview. I’m in the process of writing this all up in more detail, including some interesting though apocryphal stories of the philosophers, for a podcast episode of The Elements Unearthed. I’ll be presenting this information, and giving an overview of the project, at a Brown Bag Lunch next Tuesday, June 23, from 12:00 to 1:00 here at Chemical Heritage Foundation (315 Chestnut St., Philadelphia). The public is invited, so if you’re in the area, please stop by. It will be in the 6th floor conference room. I will have some samples of animations and images with narration for this new episode, as well as previous episodes created by my students at MATC and a presentation on the project as a whole.
One final note from this last week. I had the opportunity to attend a conference entitled “Composition to Commerce: Chemistry, History, and the Wider World” held June 12-13 at CHF. It was set up as an opportunity to hear experts in the field of chemistry history present some of their current work and to discuss the historiography of chemistry; that is, how one goes about telling the history of chemistry. Although I felt myself to be a bit of an interloper, I was excited to find that some of the best experts in the field were there – people like Lawrence Principe, William Newman, Alan Rocke, Ursula Klein, and others. In my researches here I keep coming across their names. I didn’t get the chance to talk to all of them, but at least being there and seeing them lets me know who they are. I hope to enlist their aid in this project, perhaps as Subject Experts on alchemy and the history of atomic theory that I can interview later this summer. I also found the conference interesting in how various historic alchemists/early chemists were treated and how some names I’d never heard of are now surfacing as having had an important impact on the history of chemistry, such as Gassendi, Sennert, Starkey, and others. I’ll enjoy getting to know their stories as well as the those of the better known figures such as Boyle and Lavoisier.
Anyway, wish me luck on my presentation next Tuesday. Stop in if you can. After that, I must dig into revising my application for the National Science Foundation which is due on Thursday. But more on that next week . . . .