Fantastic Metropolis

Note, for example, that if oxygen were dephlogisticated air for us, we should insist without hesitation that Priestley had discovered it, though we would still not know quite when. But if both observation and conceptualization, fact and assimilation to theory, are inseparably linked in discovery, then discovery is a process and must take time. Only when all the relevant conceptual categories are prepared in advance, in which case the phenomenon would not be of a new sort, can discovering that and discovering what occur effortlessly, together, and in an instant. Grant now that discovery involves an extended, though not necessarily long, process of conceptual assimilation. Can we also say that it involves a change in paradigm? To that question, no general answer can yet be given, but in this case at least, the answer must be yes. What Lavoisier announced in his papers from 1777 on was not so much the discovery of oxygen as the oxygen theory of combustion. That theory was the keystone for a reformation of chemistry so vast that it is usually called the chemical revolution.

—Thomas S. Kuhn, The Structure of Scientific Revolutions

It’s interesting to consider thought, and how thoughts affect other thoughts: in essence, everything we think is part of a constantly weaving pattern of thoughts interpolating with both all our own thoughts and all the thoughts we come into contact. The process Kuhn describes as a change in paradigm is in essence a total alteration of the mind. You can describe Lavoisier and Priestley’s achievement not so much as a discovery in positive as much as it was a discovery in negative, a destruction of phlogiston itself. Of course, today we know (thanks to Lavoisier and Priestley, even if Priestley could scarcely believe it) that phlogiston does not exist: that when an object is burned, its essential phlogiston (from the Greek word φλογιζω, meaning, well, to burn stuff, basically) does not escape into the ether. Therefore, thanks to Lavoisier and Priestley, we know that there’s no phlogiston to restore to the ashes of a burned object and thus recreate it exactly as it was before it was burned. This idea, born out of the works of Johann Becher and George Stahl, was an adaptation of Paracelsus’ notion of the internal essence of an object being visible through its external state (including notions of alchemical sulphur and purification) as well as explaining much of what the chemists of the time saw when they burned things.

For roughly a century, from the time of Becher and Stahl until 1774, Stahl’s proposal of phlogiston (that is, that phlogiston existed in all flammable objects, and was released from them by the process of burning them, so that ash would not burn because its essential phlogiston had been released by the fire itself) existed as dogma within chemistry. Its hold was so strong that when Priestley first experimented on red oxide of mercury and released oxygen from it via the application of fire, he called the gases released by the process dephlogisticated air and not oxygen: to Priestley, the presence of phlogiston was such a given that there was no possibility that it didn’t exist.

This is interesting to me on several levels. For one thing, these little gedankenexperiments into our Encyclopedia of Heresies often come in the form of thoughts that don’t really fit anywhere else. For instance, in Priestley’s mind, the idea that there was no phlogiston didn’t fit, and as a result, he couldn’t see what he’d accomplished. The nature of his achievement was hidden from him by his preconceptions about what it was. It fell to his rival and correspondent Lavoisier to put the big picture together, to understand what Priestley had done. Lavoisier is today credited, in my copy of The Penguin Desk Encyclopedia of Science and Mathematics (and man, I knew there was a reason I loved the clearance table at my local used book store) as “the first to have a clear concept of a chemical element and the first to list the known elements. He also developed the idea of naming compounds from elements.” Apologies to Kuhn and his excellent Structure of Scientific Revolutions, which does make the point that things are rarely that simple, but it’s useful to consider the difference between Priestley and Lavoisier here. Both were gifted chemists, both were intelligent men, both were accomplished scientists: while today phlogiston is often derided as a pseudo-scientific concept, it’s not fair to hold that against Priestley. It was as accepted as Newton’s theory of light as a material corpuscle was in its time, and no scientist would abandon it lightly. It would be like a modern scientist arguing that the laws of physics themselves are habitual, that they follow some kind of selective force. (Yes, I did work Rupert Sheldrake in again, my apologies to you who aren’t fans of Morphic Resonance.) But both Priestley and Lavoisier were living in an age where such arguments were advanced again and again, as the very nature of the chemical revolution with its distinct elements and compounds, named and ordered, would make clear: a derivation and elaboration of distinction that would make the hermetics weep with envy and lead the way into atomic science and the principles of how atoms affect each other. (If you think about it, Paracelsus’ idea of how the internal essence of an object is expressed externally works pretty well in that context.) And it was hardly the only such revolution coming down the pike: the triumph of Darwin was close to hand, and it was but recently before the development of the oxygen theory of combustion that the disparate threads of electrical experimentation worked on by the self-styled “Electricians” were beginning to come together in a unified school.