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What does science produce? (36 Views of Mount CritRat)
Earlier, I claimed the goal of science is to produce more science. Here I’ll explain what that means and describe its connection with the world we live in, which contains GPS navigation, solar cells, radio, laser eye surgery, carbon-fiber bicycles, and whatnot – all somewhere between impossible and wildly improbable without science as it is practiced.
You will likely be relieved to know that the critical rationalists appear in only two short paragraphs. The text is largely anecdotes I copied from other people.
Theory leads to theory
Here’s a way in which theory directly leads to new theory, due to Richard Feynman: Richard Feynman, The Character of Physical Law, 1967, p. 53, emphasis mine.
“Mathematically each of the three different formulations [of the law of gravitation], Newton’s law, the local field theory and the minimum principle, gives exactly the same consequences. What do we do then? You will read in all the books that we cannot decide scientifically on one or the other. That is true. They are equivalent scientifically. It is impossible to make a decision, because there is no experimental way to distinguish between them if all the consequences are the same. But psychologically they are very different in two ways. First, philosophically you like them or do not like them; and training is the only way to beat that disease. Second, psychologically they are very different because they are completely unequivalent when you are trying to guess new laws.”
The process of guessing new laws likely takes account of new experimental data. But it also comes because creativity needs a spark – an Aha! moment – and theory can work just as well. Lakatos concurs to the point he dismisses the role experimental evidence in a way that shocked Kuhn. Here is another example, from the development of Newton’s theory of gravitation (the first of Feynman’s three equivalent theories): Criticism, p. 135. I’ve added paragraph breaks. Emphasis is mine.
“Newton first worked out his programme for a planetary system with a fixed point-like sun and one single point-like planet. It was in this model that he derived his inverse square law for Kepler’s ellipse.
“But this model was forbidden by Newton’s own third law of dynamics, therefore the model had to be replaced by one in which both sun and planet revolved round their common centre of gravity. This change was not motivated by any observation (the data did not suggest an ‘anomaly’ here) but by a theoretical difficulty in developing the programme.
“Then he worked out the programme for more planets as if there were only heliocentric but no interplanetary forces.
“Then he worked out the case where the sun and planets were not mass-points but mass-balls. […] This change involved considerable mathematical difficulties, held up Newton’s work—and delayed the publication of the Principia by more than a decade.
“Having solved this ‘puzzle’, he started work on spinning balls and their wobbles. Then he admitted interplanetary forces and started work on perturbations. At this point he started to look more anxiously at the facts. Many of them were beautifully explained (qualitatively) by this model, many were not.[…]”
Notice that Newton is (per Lakatos) progressively refining his theory in a process of successively more challenging thought experiments. But I also think calculus counts as new knowledge. Even if you separate mathematics from scientific knowledge (the critical rationalists' domain), it’s indisputable that the calculus made previously-inexpressible physical theories possible.
Experiments lead to experiments
As Galison points out in Image and Logic, experimentalists are not passive technicians waiting for theorists to tell them what to try to refute. Being an experimentalist is a career and a trade. It would be weird if scientists who’ve devoted years to cloud chambers wouldn’t try to make each new one an improvement on the last, running ahead of theorists by giving them new phenomena to puzzle over. And it’s not in any way surprising that someone – name – would invent the bubble chamber as an improvement on the cloud chamber, marrying old techniques with hitherto-unused materials (not clouds but denser liquids with more particles for cosmic rays to ionize). (Both Galison and Pickering tell the story of the bubble chamber. Pickering emphasizes the irony that name originally built bubble chambers because he wanted to get back to the lone scientist doing “desktop” science, only for the resulting technology to be the exemplar of Big Science. So, after he collected his Nobel Prize, name switched to biology.)
In Galison’s account of the history of particle physics, Image and Logic, theory and practice proceed somewhat independently. The revolutionary shift from pictures of individual particle tracks (the Image in his title) to counters that gather statistical evidence (his Logic) didn’t sync up with any revolution in theory, and the quantum revolution in theory didn’t cause a revolution in experimental practice.
pictures
The nature of experiment
I like Ian Hacking’s definition of experimentation: “the production of stable phenomena, one that occurs regularly under definite circumstances.“ Representing and Intervening, p. 221 He later adds that it is usually the “deliberate creation of stable new phenomena.“ .ibid, p. 249, my emphasis. p. 249.
Experimentalists are in the business of wrestling an obdurate nature into producing ever-newer phenomena. Less fancily: they make new things happen, things no one had ever seen happen before. They do this by creating a place – the laboratory – where the parts of nature that make the phenomenon hard to create can be excluded. They regularize an environment, reduce the number of variables they’d have to worry about.
This work interacts with theory but is not driven by it.
Experiments expand
A phenomenon that only appears in carefully controlled environments inspires less confidence than one that is stable in a wider set of “definite circumstances.” I can’t cite anything, but it seems to me that must be true even of theorists. I’m reminded of C.S. Peirce’s comment about philosophy: Charles Saunders Peirce, 1868. (Quoted in Galison, /Image and Logic/, 1997)
“Philosophy ought to imitate the successful sciences in its methods … [T]o trust … rather to the multitude and variety of its arguments than to the conclusiveness of any one. Its reasoning should not form a chain which is no stronger than its weakest link, but a cable whose fibres may be ever so slender, provided they are sufficiently numerous and intimately connected.”
Exhibiting a phenomenon in many laboratories that control their environments differently increases confidence.
In Science in Action, Bruno Latour takes this further, describing a pivotal moment in immunology:
There was nothing more dramatic at the time than the prediction solemnly made a month in advance by Pasteur that on 2 June 1881 all the non-vaccinated sheep of a farm in the little village of Pouilly-le-Fort would have died of the terrible anthrax disease and that all the vaccinated ones would be in perfect health. […] we find a fascinating negotiation between the Pasteur and the farmers' representatives on how to transform the farm into a laboratory. Pasteur and his collaborators had already done this trial several times inside their lab, reversing the balance between man and diseases […] Still, they had never done it in full-scale farm conditions. But they are not fools, they know that in a dirty farm thronged by hundreds of onlookers they will be unable to repeat exactly the situation that had been so favorable to them […] On the other hand, if they ask people to come to their lab no one will be convinced […] They have to strike a compromise with the organizers of the field test, to transform enough features of the farm into laboratory-like conditions – so that the same balance of forces can be maintained – but taking enough risk – so that the test is realistic enough to count as a trial done outside.”
Latour’s career was largely about how science expands both belief and effectiveness by gradually “enlisting” people and things to make phenomena appear in ever-wider circumstances. Alternately: circumstances with fewer constraints, more unregulated influences.
Alternately, the approach is to be able to package the laboratory into ever smaller and cheaper containers. I have on our living room wall a platter from a spinning-metal disk drive circa 1979. That surface held, I think, one megabyte of data (and another megabyte on the back side). The entire assembly was ten of those platters, stacked on a spindle, put into a cabinet about the size of a dishwasher.
Nowadays, such disks are nearly obsolete. However, my NAS has two redundant four-terabyte disks, each in a tidy little package. Part of the increase in information density is due to new theory, but a good deal is also due to people learning how to better isolate the interior of the disk drive from its environment.
The conclusion
The upshot of all this is that:
- There’s no clear boundary between experimentalists and engineers. Rather, engineers progressively loosen a quarantine experimentalists are allowed to maintain.
- Experimentalists are informed by theoretical considerations, but they are not necessarily driven by them. Each culture cherry-picks results from the other to advance private agendas.
- Because experimentalists are involved with doing things in the world, they form a natural bridge between theorists and engineers/commercialization.
And my addition:
- Because theorizing is really cheap and anyway it’s hard to stop theorists from theorizing, understanding (more expensive) experimentation and its relationship to application is way more important than being all picky about what kind of behavior makes for a morally acceptable theorist. As the critical rationalists do.