Ladyman & Ross - Every Thing Must Go chapter 1

I've been reading Every Thing Must Go by James Ladyman and Don Ross (hereafter L&R). The first chapter, provocatively titled "In Defense of Scientism," argues that metaphysics, if it is to have any hope of arriving at knowledge of the world, must be closely connected with science (particularly physics). We can't learn anything about the fundamental structure of reality by sitting in our armchairs. Accordingly, L&R think that the vast majority of work in contemporary metaphysics is completely misguided. While I'm not quite as critical as L&R are, I definitely have a lot of misgivings about the degree to which many debates in contemporary metaphysics are alienated from the sciences. Here are some notes on this chapter.


1.1 Naturalistic Metaphysics

In this section, L&R outline naturalistic metaphysics, their alternative to current mainstream metaphysics (which they call "Neo-Scholastic Metaphysics," a term of abuse that doesn't seem entirely fair to the Scholastics given their major contributions to the development of science). Put simply, naturalistic metaphysics is metaphysics that attempts to unify hypotheses accepted in contemporary science.

Much contemporary metaphysics is concerned with "domestication": making scientific discoveries compatible with our commonsense or folk pictures of the world. Accordingly, metaphysical theories are judged by how well they accord with common sense, and the appeal to intuitions is endemic in metaphysical argumentation. Most philosophers take it as a point in favour of a theory if it accommodates our intuitions, and a point against a theory if it violates our intuitions. That is, most philosophers accept something like:

(A) If P is (counter)intuitive, we have some reason to (dis)believe that P.

L&R note that one of the central problems with this is that our cognitive capacities have not evolved to track truth in all domains of inquiry. They suggest that cognitive capacities are likely to be truth-tracking with respect to social coordination and navigation around medium-sized objects, but beyond this, there's no reason to expect us to be reliable. So their objection to contemporary metaphysics is essentially an evolutionary debunking argument. Following Kahane 2011, we might formulate it like so:

(P1) (Causal premise) Our intuitions about metaphysics are explained by our evolutionary history.
(P2) (Epistemic premise) Evolution is not truth-tracking with respect to metaphysics.
(C) So, our intuitions about metaphysics are unjustified.

In fact, I think this argument is rather too narrow. Debunking arguments need not be limited to evolution, and the argument against metaphysical intuitions works just as well if we suppose, as is plausible, that our intuitions arise from social rather deeper evolutionary influences. The important point is that the relevant cause isn't truth-tracking.

Of course, the obvious worry about this kind of argument is that it applies to the sciences as well. I doubt that the reproductive success of our ancestors would have been promoted by their having the right kind of intuitions about physics, or biochemistry, or neuroscience, etc, so evolution isn't truth-tracking with respect to any of these either. (Except in very limited domains: presumably we've evolved an "intuitive physics" that's at least approximately correct for medium-sized objects. Note though that even here, "intuitive physics" often goes wrong; see McCloskey 1983.)

The answer to this difficulty is to note two things: (a) As L&R note, evolution is truth-tracking with respect to everyday, medium-sized objects. Organisms need to identify obstacles, threats, resources, etc. That's one of the central jobs of the brain. We can therefore have a lot of confidence that most of our everyday observations - "the rat is running faster than the mouse," "there's a tree in the garden," "that man is walking towards me" - are correct. (b) The sciences are built up from or based on everyday observations. One way to spell this out might be to say that scientific observations are just everyday observations informed by theory. For example, I see a trail in a misty substance. This is a standard everyday observation. Applying modern physical theory to this, I see a subatomic particle in a cloud chamber.

If we accept (a) and (b), then the sciences are immune from the debunking argument. And again, note that while I talked about evolution there, I'm pretty sure that (a) and (b) would also work to insulate science from the "social debunking argument." It's socially useful to track the truth about everyday objects, etc. Of course, at this point L&R will need to argue that (b) cannot also be used to save contemporary metaphysics. This is where things get a bit tricky, because prima facie a great deal of the contemporary metaphysics that L&R seek to impugn seems to be based on everyday observations. Here are a few quotes from the SEP article on metaphysics:

Consider a gold statue. Many metaphysicians contend that there is at least one material object that is spatially co-extensive with the statue, a lump of gold.

Tibbles is a cat. Call his tail "Tail". Call all of him but his tail "Tib". Suppose Tail is cut off—or, better, annihilated. Tibbles still exists, for a cat can survive the loss of its tail. And it would seem that Tib will exist after the "loss" of Tail, because Tib lost no part. But what will be the relation between Tib and Tibbles?

Consider a mundane claim: an iceberg caused the Titanic to sink. Does the causal relation hold between two events: the event of the ship hitting the iceberg and the event of the ship sinking? Or does it hold between two sets of states of affairs?

In all of these quotes, we have an appeal to everyday observations - gold statues, cats and their tails, icebergs hitting ships. Must we reject the debunking argument against metaphysics? I'm not so sure. Here are two possible objections to this move. First, it's worth emphasizing that the debunking argument is an argument specifically against the appeal to intuitions. Saying "an iceberg caused the Titanic to sink" is one thing. What the debunking argument targets is the use of intuitions in developing a theory of causation that aims to explain such facts about causation. Second, an important thing to note about the above examples is that the observations, e.g. "an iceberg caused the Titanic to sink," don't really play any role in supporting the metaphysical theory; they're just examples used to introduce the topic and any other observation of the same form would have done (e.g. anything of the form "X caused Y" can serve to introduce problems of causation). This isn't unusual. Everyday observations generally only play an illustrative role in metaphysics. Different metaphysical theories tend to be compatible with all of our everyday observations. What will be the relation between Tib and Tibbles? As far as everyday observations are concerned, the answer doesn't make any difference.


Obviously, L&R's project isn't going to be popular among most contemporary metaphysicians. L&R also point out another source of resistance, this time from philosophers they're happy to call naturalists: those philosophers who hold that the sciences and perhaps the world in general are fundamentally disunified (e.g. John Dupré, Ian Hacking, Nancy Cartwright). This view is anathema to L&R's view that metaphysics is concerned with unification. L&R say explicitly on pg 5 that "if the world were fundamentally disunified, then ... there is no metaphysical work to be done."

Now, it's not obvious that L&R's conclusion follows. Let's formalize the argument:

(P1) Naturalistic metaphysics attempts to unify hypotheses accepted in contemporary science.
(P2) The world is fundamentally disunified.
(C) There is nothing for naturalistic metaphysics to do.

But global disunity doesn't prevent local unifications, i.e. even if the world in general is disunified, this doesn't stop us from showing that particular parts of it are unified. The disunity of science wouldn't make us unable to talk about reductionism, or natural kinds, or causation, etc in particular cases, and thus provide particular unifications. In fact, I think even global metaphysical claims could be made. Even granting disunity, it could still be the case that there are commonalities in e.g. the concepts of causation used in each science. Elucidating these continuities would involve showing a respect in which the world is unified.

I suspect that L&R are led to their conclusion by assuming a stronger version of disunity than anybody who argues for disunity actually holds. They say, for instance (this comes directly after the last quote): "objective inquiry would start and stop with the separate investigations of the mutually unconnected special species." But whoever said that the sciences are unconnected? That's much stronger than the disunity claim. Here, for instance, is Dupré on the limits of reductionism (1993: 106): "reductive explanation is required to account for how things of a certain kind do what they do; but they typically do not help us to understand or to predict what, among the behaviours of which it is capable, a complex thing will do." Note that L&R cite Dupré and that book in particular as an example of a philosopher who supports disunity. But evidently, Dupré doesn't claim that the sciences are unconnected. Physics can tell us a lot about chemistry, and chemistry a lot about biology, and biology a lot about psychology, etc. If we want to know how biological entities do what they do, we're going to have to do some physics and chemistry.

So I'm not sure that L&R's principle for demarcating useful from useless metaphysics - i.e., the focus on unification - really rules that metaphysics is only possible if the world as a whole is fundamentally unified. But even so, I'd say that this principle is still too strict. In fact, the very project of coming up with a principle for demarcating good from bad metaphysics is misguuided in my view. I don't know how to say exactly when metaphysics is too far removed from science, too much based on intuitions, etc. But I know it when I see it. Something like On the Plurality of Worlds is simply on the wrong track, whereas Every Thing Must Go and The Disorder of Things are on the right track, at least as far as methodology is concerned. Who cares about principles?


Well, I think that's enough for now. I'll write up my notes for the rest of the chapter in some later posts.


Dupré, J. (1993) The Disorder of Things, Cambridge, Mass.; London: Harvard University Press.

Kahane, G. (2011) "Evolutionary Debunking Arguments", Noûs, vol. 45, no. 1, March, pp. 103-125.

McCloskey, M. (1983) "Intuitive Physics", Scientific American, vol. 248, no. 4, April, pp. 122-130.