There are some interesting recent parallels in what one may call the philosophy of science, that have to do with the issues related to determinism, reductionism, and our struggle to understand complex trait causation in terms resembling 'laws' of Nature. We discussed a lead-in to this the other day.
If life is just a kind of fancy molecular biochemistry, and molecules obey fundamental, universal physical laws, then mustn't life also follow the same laws? If not, what does that mean and what could be the evidence? How could the laws be suspended? And at what level would purely material, molecular/energy stop applying?
Answering these kinds of questions is problematic (because we have no actual answers), but nonethless shows an important way in which even asking the questions is not entirely about science but is also profoundly affected by sociocultural and historical circumstances. These circumstances are complex, but have to do not just with the technology and methods that are available at any given time, but also with what is acceptable to think in the first place.
Darwin and the excitement that his attempt at a universal physics-like theory of life (evolution by natural selection, implying rather strong genetic determinism) was an exciting event in science. It threatened established scriptural religion, and its proponents felt highly empowered to rip religion based on faith in one kind of scripture for what in many ways amounted to faith in another accepted word--that of Darwin.
Since adaptive evolution of a natural kind (not that done in labs, or in agricultural breeding, or via pesticides and antibiotics, etc.) took place imperceptibly slowly and in the past, we must rely on indirect explanations and interpretations of the evidence. Ever since Darwin, there have been widespread and rather hubristic declarations of selective stories about this trait or that--or, by some, the belief (and that's the right word for it) that basically everything in life is the result of specific adaptive selection.
More than that, along with striking research success in identifying genes, the historical belief developed that reductionism--ultimately, molecular explanations of everything. Molecules are the sexy total truth of the world according to that view. But such a view is not just objective science; instead, it also reflects society at large, as is very clear from the history of the life sciences since Darwin's time.
Gotcha! regains acceptability
History affects what is accepted or followed or believed. Darwin stole explanations of life away from religion. Among other things was the idea that what we are is inherited and is here only because it was adaptively successful in the past. This was a view of biological inherency. As is well known, this immediately spawned the eugenics era. The idea was that now that we (that is, elite scientists, mainly males) know the real truth of the nature of organisms, we can control rather than be controlled by Nature. We can guide our evolution with this knowledge. In a kind of extension or rebirth of the Utopianism of the 18th century, we could purge society of its ills and replace them with only that which is good. Of course, now we were talking about people, not just social and governmental structures. This means determining who reproduces and who does not, which is the ultimate value judgement that needed to be made if we were to imitate and speed-up the beneficent goals of Nature. It might be harsh, if only some reproduce and others don't (or are prevented from it), but Nature itself is harsh, and so on.
This led beyond the rather piously benign idea that someone in authority would decide who could mate, to the less benign idea that someone in authority would decide who could survive. Over several decades, this idea terminated (so to speak) in the Nazi death camps. By the end of WWII, the eugenic view that who and what you were was dictated by your genes became so discredtied and distasteful that scientists developed a very different view.
This was the behaviorist or environmentalist view. In psychology it was lead by BF Skinner in that period, especially in the US. The idea was that what you are was based on your experience, not your inborn tools. This was not a new idea, but genetic inherency had taken over as the prevailing view for nearly a century, and the view, whether informal or formal in regard to rejecting eugenics, was the environmentalist view.
In this view, reduction to genetics was not really thought to be of any use. Whatever the mechanism or how brought about by genes, that (the brain, neurons, etc) internal stuff was just not relevant to understanding the traits--behavior, mainly--of the person. Reductionism was not going to gain any insights, even if certainly the mechanisms must involve genes and nerves and so on. It was even said that you could (or should) just assume that an organism was entirely empty inside! We just need to look at the outside not the inside of our subjects. We did not need to know anything about the insides to understand behavior, and trying to work out the way the complex wiring worked was a waste of time. A recognition of the complexity of traits like behavior. Indeed, for his time, Darwin had little alternative, but this--considering the trait, not the internal generative mechanism--was essentially what he studied in so much detail.
Cachet and cash, eh?
The evidence didn't change, but behavioral approaches and environmental determinism took over. Indeed, the evidence isn't changing very much even now. We know a bit about neuroscience that is relevant to behavior, but we're still not really explaining behavior in any serious sense by invoking this gene or that one. But what is pursued, what people 'believe in' and get
dogmatically excited about, and what is allowed or considered
acceptable (whether for explicitly understood reasons or not) is changing. As memory fades, and new practitioners replace the WWII generation, genetic determinism and inborn inherency are rapidly regaining respectability. There is simply too much cachet--and too much cash!--in 'modern' technical science, and too little revulsion at what we know has been done in the name of imposing value judgements by one group against another (using religion, science, or whatever else) as expedient justifications, for this reversal of what is acceptable to swing back the other way.
What we accept is not just based on hard-core science decisions, but to a huge extent depends on
historical context as well. Will it turn sour again? The probability may be low but is certainly not zero, because elitist expert-based decisions on how society should be run (by them) for its betterment (as they see it) are just hard to keep down.
Of course, we
are no more genetically determined, or not, than during Hitler and the
prior eugenics times. So there is no serious scientific reason for this swing back to earlier once-discredited ideas. But it is now savory to believe in it, as
higher-level analysis fails to answer questions (as it did before
eugenics) we return to reductionistic inherency. It just seems
technological, real science, and it's lost its odor of abuse. A new
generation reinvents its beneficence for society. The sexy tools (genome sequencers, fMRI scanners, and much more) are available and so are the grant funds and the journals hungering for The New Discovery (after all, should journalists remember the past any better than scientists do?).
If behavioral and evolutionary psychology can't keep their hands off this potential societal dynamite, they're not alone by any means. Genomics and other omics are beating on the same drum, assuming that traits like obesity must be understood not on their own terms but by looking 'inside' the organism to understand them. Of course, there is and always has been reason for trying to understand how things work. But there isn't enough understanding, not yet at least, for this to come nearly to what is being promised.
Still, at present, we haven't got good law-like alternatives. Are there laws of how underlying mechanisms must work, how the determine complex traits, or whether in fact inherently probabilistic things may mean that reductionism simply cannot work very well for the kinds of explanations being sought.
At the very least, more circumspection is what is in order.