Philosophy

Steven Pinker has kicked up a cloud of dust with a seemingly mild claim, addressed to people in the humanities: Science Is Not Your Enemy. And he’s right, it’s not! Science is merely an extremely effective method for gaining empirical knowledge of the world, and empirical knowledge of the world should not strike fear into any self-respecting intellectual person. Or if it does, perhaps you should contemplate a different form of employment, like U.S. Senator.

The devil is in the details, of course, and plenty of people have objected to the specific ways in which Pinker has argued that science is your friend, and others have defended him. Here are takes by Jerry Coyne, Eric MacDonald, and Massimo Pigliucci. I don’t mean to add anything deep or comprehensive to the debate, but I do want to make a suggestion that, if adopted, would make the world a better place: the word “scientism” should be dropped from the vocabulary of this discussion.

Now (like Pinker), I am a descriptivist rather than a prescriptivist when it comes to language. Word usage is not “right” or “wrong,” it’s just “useful” or “unhelpful.” So the point here is that use of the word “scientism” is unhelpful, not that people are using the “wrong” definition. It’s unhelpful because it’s ill-defined, and acts as a license for lazy thinking. (It wasn’t too long ago that I acknowledged the potential usefulness of the term, but now I see the error of my ways.)

The working definition of “scientism” is “the belief that science is the right approach to use in situations where science actually isn’t the right approach at all.” Nobody actually quotes this definition, but it accurately matches how the word is used. The problem should be obvious — the areas in which science is the right approach are not universally agreed upon. So instead of having an interesting substantive discussion about a real question (“For what kinds of problems is a scientific approach the best one?”) we instead have a dopey and boring definitional one (“What does the word `scientism’ mean?”).

I don’t know of anyone in the world who thinks that science is the right tool to use for every problem. Pinker joins Alex Rosenberg, who has tried to rehabilitate the word “scientism,” claiming it as a badge of honor, and using it to mean a view that “the methods of science are the only reliable ways to secure knowledge of anything.” But even Alex firmly rejects the idea that science can be used to discover objective moral truths — and others think it can, a view which is sometimes labeled as “scientism.” You can see the confusion.

Someone might respond, “but `scientism’ is a useful shorthand for a set of views that many people seem to hold.” No, it’s not. Here are some possible views that might be described as “scientism”:

• Science is the source of all interesting, reliable facts about the world.
• Philosophy and morality and aesthetics should be subsumed under the rubric of science.
• Science can provide an objective grounding for judgments previously thought to be subjective.
• Humanities and the arts would be improved by taking a more scientific approach.
• The progress of science is an unalloyed good for the world.
• All forms of rational thinking are essentially science.
• Eventually we will understand all the important questions of human life on a scientific basis.
• Reductionism is the best basis for complete understanding of complicated systems.
• There is no supernatural realm, only the natural world that science can investigate.

The problem is that, when you use the word “scientism,” you (presumably) know exactly what you are talking about. You mean to include some of the above supposed sins, but not necessarily all of them. But if you aren’t completely explicit about what you mean every time you use the term, people will misunderstand you.

Indeed, you might even misunderstand yourself. By which I mean, using vague words like this is an invitation to lazy thinking. Rather than arguing against the specific points someone else makes, you wrap them all up in a catch-all term of disapprobation, and then argue against that. Saves time, but makes for less precise and productive discussion.

Given that the only productive way to use a word like “scientism” — something vaguely sinister, ill-defined, used primarily as an accusation against people who would not describe themselves that way — would be to provide an explicit and careful definition every time the word is invoked, why use it at all? I’m not saying you can’t disagree with specific claims made by Pinker or anyone else. If you think people are making some particular mistake, that’s fine — just say what the mistake is.

I take the main point of Pinker’s piece to be the same as Feynman’s discussion of the beauty of a flower, or Dawkins’s Unweaving the Rainbow — science is not opposed to the humanities or the arts, but enhances them by giving us a deeper understanding. With that, I couldn’t agree more. We can disagree with some of the specific contentions in a constructive way, but lumping everything we don’t like into one catch-all word isn’t useful.

TL;DR: The word “scientism” doesn’t helpfully delineate a coherent position, it unhelpfully flattens important distinctions and creates a false target. We can do better.

Richard Marshall at 3AM magazine has been doing a series of interviews with all kinds of thinkers, especially philosophers; some recent examples include Dan Dennett, Tim Maudlin, Rebecca Kukla, Alex Rosenberg, and Craig Callender. And I’m the latest subject. Given the venue, we talk as much (or more) about philosophy than about physics, and a lot about how they fit together.

Spoiler alert: I think it’s possible to have productive grown-up interactions between philosophy and science. I guess I’m just a radical bomb-thrower at heart.

Click through if this kind of thing floats your boat:

I think emergence is absolutely central to how naturalists should think about the world, and how we should find room for higher-level concepts from tables to free will in a way compatible with the scientific image. But “weak” emergence, not strong emergence. That is simply the idea that there are multiple theories/languages/vocabularies/ontologies that we can use to usefully describe the world, each appropriate at different levels of coarse-graining and precision. I always return to the example of thermodynamics (fluids, energy, pressure, entropy) and kinetic theory (collections of atoms and molecules with individual positions and momenta). Here we have two ways of talking, each perfectly valid within a domain of applicability, but with the domain of one theory (thermodynamics) living strictly inside the domain of the other (kinetic theory). Crucially, the “emergent” higher-level theory can exhibit features that you might naively think are ruled out by the lower-level rules; in particular, thermodynamics famously has an arrow of time defined by the Second Law (entropy increases in isolated systems), whereas the microscopic rules of the lower-level theory are completely time-symmetric and arrowless.

I think this example serves as a paradigm for how we can connect the manifest image to the scientific image. Sure, there’s nothing like “free will” anywhere to be found in the ultimate laws of physics. But that’s not the only question to ask; at the higher-level description, we should ask whether our best emergent theory of human beings includes the idea that they are (in the right circumstances) rational decision-making agents with freedom of action. Until we come up with a better description of human beings, I’m perfectly happy to say that free will is “real.” It’s not to be found in the most fundamental ontology, but it’s not incompatible with it either; it’s simply a crucial part of our best higher-level vocabulary.

There is an old parable — not sure if it comes from someone famous I should be citing, or whether I read it in some obscure book years ago — about a lexicographer who was tasked with defining the word “taxi.” Thing is, she lived and worked in a country where every single taxi was yellow, and every single non-taxi car was blue. Makes for an extremely simple definition, she concluded: “Taxis are yellow cars.”

Hopefully the problem is obvious. While that definition suffices to demarcate the differences between taxis and non-taxis in that particular country, it doesn’t actually capture the essence of what makes something a taxi at all. The situation was exacerbated when loyal readers of her dictionary visited another country, in which taxis were green. “Outrageous,” they said. “Everyone knows taxis aren’t green. You people are completely wrong.”

The taxis represent Science.

(It’s usually wise not to explain your parables too explicitly; it cuts down on the possibilities of interpretation, which limits the size of your following. Jesus knew better. But as Bob Dylan said in a related context, “You’re not Him.”)

Defining the concept of “science” is a notoriously tricky business. In particular, there is long-running debate over the demarcation problem, which asks where we should draw the line between science and non-science. I won’t be providing any final answers to this question here. But I do believe that we can parcel out the difficulties into certain distinct classes, based on a simple scheme for describing how science works. Essentially, science consists of the following three-part process:

1. Think of every possible way the world could be. Label each way an “hypothesis.”
2. Look at how the world actually is. Call what you see “data” (or “evidence”).
3. Where possible, choose the hypothesis that provides the best fit to the data.

The steps are not necessarily in chronological order; sometimes the data come first, sometimes it’s the hypotheses. This is basically what’s known as the hypothetico-deductive method, although I’m intentionally being more vague because I certainly don’t think this provides a final-answer definition of “science.”

The reason why it’s hard to provide a cut-and-dried definition of “science” is that every one of these three steps is highly problematic in its own way. Number 3 is probably the trickiest; any finite amount of data will generally underdetermine a choice of hypothesis, and we need to rely on imprecise criteria for deciding between theories. (Thomas Kuhn suggested five values that are invoked in making such choices: accuracy, simplicity, consistency, scope, and fruitfulness. A good list, but far short of an objective algorithm.) But even numbers 1 and 2 would require a great deal more thought before they rose to the level of perfect clarity. It’s not easy to describe how we actually formulate hypotheses, nor how we decide which data to collect. (Problems that are vividly narrated in Zen and the Art of Motorcycle Maintenance, among other places.)

But I think it’s a good basic outline. What you very often find, however, are folks who try to be a bit more specific and programmatic in their definition of science, and end up falling into the trap of our poor lexicographic enthusiasts: they mistake the definition for the thing being defined.

Along these lines, you will sometimes hear claims such as these:

• “Science assumes naturalism, and therefore cannot speak about the supernatural.”
• “Scientific theories must make realistically falsifiable predictions.”
• “Science must be based on experiments that are reproducible.”

In each case, you can kind of see why one might like such a claim to be true — they would make our lives simpler in various ways. But each one of these is straightforwardly false. …

What Is Science?Read More »

In Jim Holt’s enjoyable book, Why Does the World Exist? An Existential Detective Story, he recounts conversations with a wide variety of thinkers, from physicists and biologists to writers and philosophers, who have struggled with the Primordial Existential Question. You probably know my take on the issue, but Jim and I sat down at the LA Library a few weeks ago to chat about this and related issues. I think it’s safe to say we at least had a few laughs. Here’s the complete video; audio is also available as a podcast.

Jim Holt and Sean Carroll from ALOUDla on Vimeo.