There was another round of the “who counts as a scientist?” debate recently, on Twitter and then on the Physics Focus blog. In between those, probably coincidentally (he doesn’t mention anything prompting it), Sean Carroll offered a three-step definition of science:
- Think of every possible way the world could be. Label each way an “hypothesis.”
- Look at how the world actually is. Call what you see “data” (or “evidence”).
- Where possible, choose the hypothesis that provides the best fit to the data.
This isn’t quite the way I would put it– I’m an experimentalist where Sean’s a theorist, so I tend to give more weight to observation while he gives more weight to theorizing– but it’s not bad. It is, however, missing a critical element, in my opinion. There’s a fourth step to the process, without which it can’t be considered complete, namely:
4) Share your results with everybody else.
This may not seem like it belongs on the same footing as the more philosophical and abstract steps Sean gives, but I’m not much for philosophy. And on a practical level, you can’t really have science as we know it without sharing results. It’s not an accident that the rapid explosion of scientific progress in Europe roughly coincides with the rise of the professional scientific societies and all the other trappings of modern institutional science– regular meetings, journals reporting the latest discoveries, etc.. Things really get moving, in terms of scientific knowledge, between the early 1600’s when Galileo and his contemporaries were encoding their astronomical discoveries in Latin cryptograms and the early 1800’s when Michael Faraday provided his own three-step guide to scientific success: “Work. Finish. Publish.” That last step is a big part of the reason.
My knowledge of the history of science generally is not terribly systematic– I’ve read bits and pieces about specific eras I find interesting for one reason or another, but not that wide a range. I have the impression, though, that rapid progress is always associated with groups rather than individuals. The fragmentary knowledge we have of ancient science generally involves groups of philosophers in dialogue with one another, and even where you have dramatic progress attributed to single individuals, on closer inspection, they’re usually tied into a network of other like-minded folks. Modern myth has Einstein devising relativity in isolation, but even when he was a patent clerk, he exchanged ideas with friends and colleagues, chiefly Michele Besso. And Marcel Grossmann was essential to the development of general relativity, which stretched out over nearly a decade, during which Einstein became extremely well integrated with the network of physics in Europe.
If you want a real example of a lone solitary genius in science, it’s not Einstein you should talk about, but Ernst Stueckelberg. If you just said “Who?,” that’s exactly my point. Stueckelberg was a Swiss physicist who almost certainly worked out something very close to the modern understanding of quantum electro-dynamics (QED) years before Schwinger, Feynman, and Tomonaga. He’s not well known, though, and his discoveries are basically ignored (relegated to regretful postscripts in most of the histories of 20th century physics) because he didn’t share them very well. His only real connection to the international physics network was Wolfgang Pauli, who apparently talked him out of publishing some results that later made others famous. When he did publish results, he mostly sent them to obscure journals, and used idiosyncratic notation that other physicists found difficult to follow. Consequently, he had very little impact.
(Interestingly, he was interviewed for a few of the histories I’ve read recently, and surprisingly, didn’t appear to be bitter about any of this.)
While pop culture might suggest otherwise, science is fundamentally not a solitary pursuit. Even when you’re dealing with pencil-and-paper theory, where a single scientist can in principle make a key discovery (as opposed to needing a thousand-person LHC collaboration), science doesn’t make progress in isolation. A discovery isn’t a breakthrough until it’s shared with others, who can check the idea for themselves, and help build on it.
This is also why stories like Wiles proving Fermat’s theorem, or Grisha Perelman solving the Poincaré conjecture, or this story about a Shinichi Mochizuki maybe solving another huge problem in math have a lot of pull among scientists. It’s because lone geniuses working out solutions to huge problems without ever talking to anybody else about it is really, really strange. That’s not generally how science is done. Particularly in the cases of Perelman and Mochizuki, who basically dropped their (maybe) proofs on the community, and disappeared. It’s also a major factor in the negative reaction to the Eric Weinstein theory-of-everything business a little while ago– people in science react very negatively to supposed breakthroughs by outsiders in isolation in part because it’s Not How We Do Things.
Returning to the question of who should be considered a scientist, to be honest, I think it’s probably the second least interesting conversation it’s possible to have about science. I’m pretty much happy to let anybody who follows the general practices of science call themselves a scientist. Sean’s definition is pretty good, provided you add that final step. Without it, what you have isn’t science, but alchemy.
(Of course, I have my own formulation of the basic process, and am working on a book built around that. And I’m currently working on chapters from the tell-everyone-about-it section, so I pretty much had to post this at some point…)