Why you should rationally stick with science

Be from Missouri, the show-me state.

The good determinist aims to convince you that it’s senseless to suppose you or anyone else could have turned out otherwise given the environmental and genetic circumstances that actually explain how people turn out. If you already agree with this, terrific, and all of what’s below in this installment will likely be dead obvious. (As always, I welcome your corrections.) But many folks will balk at such a bald statement of determinism, supposing that no, there must be a way for each of us to have made different choices as we grew up, whatever our circumstances.

One way to wiggle free of determinism - the pragmatic, not universal variety (see the previous installment) - is simply to deny that, when it comes to human nature, we should place our bets with science as our way of knowing what’s true. After all, it’s a scientific, empirical observation that causal laws and relations exist at multiple levels that apply to us, so if there are other ways of knowing that certify a human exemption from causation, that show we could have done otherwise in our formative circumstances, then we can claim a very strong sort of self-authorship not available to the determinist. The question, therefore, is what rivals to science exist that warrant our rational allegiance and provide an alternative picture of human agency, one that says you could have turned out otherwise, but simply chose not to?

The curt answer: none. But perhaps a little back-up is in order. Most folks are commonsense empiricists when it comes to practical matters, such as finding a good doctor, car mechanic, computer, phone, or hairdresser. That is, they’ll look for what they take to be reliable, objective, observation-based evidence to inform their selection, not just take any old person’s word for it. Most folks won’t consult a psychic or Ouija board when it comes to matters of consequence that affect their health and security, and those that do don’t fare as well. To place your bet with empirical evidence when it comes to deciding what’s factually the case is thus quintessentially rational on the assumption you want to fare well, not poorly. And science is the paragon of empirical, observational inquiry, having investigated just about any question of fact you can imagine, for instance how many wombats typically cohabit in living situations. (I just imagined this question, and the answer is that wombats are typically loners.) If you think you know better than what scientific experts in their domain of expertise know given their investigations, then a fair question is to ask for evidence of your epistemic superiority.

If this much is obvious, the next question is: on what matters of consequence, if any, should you abandon the empirical requirement exemplified by science when deciding questions of fact, of what you should believe about the world? In practice, people frequently abandon science when observation-based conclusions about human nature conflict with received dogma, faith, sacred texts, and ideological (not just religious) authorities. And sometimes they’ll claim that their non-observational, non-empirical brand of evidence, e.g., a near-death experience of heaven, grounds an equal claim to truth as any empirical evidence.

But why, suddenly, should we abandon the empirical requirement on belief when it comes to any matter of fact? Why declare a certain set of facts to be outside the ambit of science? True, we may not particularly like what science has to say about us, for instance that we are mortal beings, sans souls, and that we are products of causal regularities - biological, environmental, and social - that determine our character, tastes, and behavior. But since when has truth been obliged to conform to what we’d like to be the case? To carve out an exception to empiricism driven by our desires or hopes doesn’t work in everyday life, so why suppose it’s a reliable guide to truth when deciding more momentous questions about human nature? To claim as much seems arbitrary.

It’s possible, no doubt, to argue that it’s emotionally rational to partition sets of facts between those that are empirically decidable and those given an observational pass; this way we have two ways of knowing deployed in their respective domains. Maybe we human beings aren’t capable of handling deep empirical truths about ourselves, so are better off believing things that aren’t observationally warranted. When it comes to determinism, perhaps the psychic cost of believing we’re not causal exceptions to natural laws is prohibitive, in which case some might argue we should rationally resign ourselves to believing that we are such exceptions. The difficulty, however, is that when it comes to human nature, science insists on a set of factual claims which conflicts with those grounded unscientifically. Those who depart from science when it comes to human nature can’t say that fear of determinism justifies that departure: fear alone isn’t a rational basis for belief. They have to come up with a principled reason why facts about human nature aren’t empirically decidable and that we should believe what non-science says. If they can’t, then it seems to me they’re being irrational. But perhaps you can demonstrate the rationality of departing from science in deciding what sort of beings we are, in particular deciding the question of whether we can contravene causation in our development and behavior.

Meanwhile, the good determinist recommends that in your epistemic disposition you hail from Missouri, the unofficial state motto of which is quintessentially empiricist: Show Me! For a more detailed defense of the rationality of sticking with science, and how it leads to naturalism as a worldview, see Reality and its rivals: putting epistemology first and the epistemology page at naturalism.org.

Up next: correcting misperceptions about pragmatic determinism.