To Appear in Being Reduced Oxford University Press Edited by J. Hohwy and J. Kallestrup Why There Is Anything except Physics1 In the course of defending his view of the relation between the special sciences and physics from Jaegwon Kim’s objections Jerry Fodor asks “So then, why is there anything except physics? That, I think, is what is really bugging Kim. Well, I admit that I don’t know why. I don’t even know how to think about why. I expect to figure out why there is anything except physics the day before I figure out why there is anything at all, another (and presumably related) metaphysical conundrum that I find perplexing” (Fodor 1998 p.161) Why is Fodor perplexed and Kim (allegedly) bugged by the existence of anything, i.e. any sciences, other than physics? I think the explanation is this. Fodor and Kim both believe (1) All items belonging to the ontologies of the special sciences (all special science individuals, events, properties etc.) are constituted or realized by or in someway made up out of the microphysical entities, properties, and quantities that are the subject matter of fundamental physics. 1 This paper is a companion piece to my “Why Is There Anything Except Physics?” and tries to partly answer that question. Earlier versions of this paper were given at the University of Missouri, Brown University, Columbia University, and at the Conference Being Reduced in Aarhus. I am grateful to members of those audiences and to Katalin Balog, Tim Crane, and the editors Jesper Kallestrup and Jakob Hohwy of Being Reduced for comments on an earlier version. My ideas on the matters discussed in this paper arise from hours and hours of discussion with David Albert to whom I am enormously grateful. 1 1 and (2) The dynamical laws of microphysics are complete in the domain of microphysics.2 Fodor but not Kim also maintains that (3) There are autonomous special sciences with their own natural kinds, laws, explanations, causal relations, confirmation relations that are not reducible to those of physics. Exactly what anti-reductionists mean by “reducible” is often not clear. But this much can be said about Fodor’s view of the relationship between special sciences and physics. He thinks that each special science taxonomizes nature into natural kinds in terms of its own proprietary vocabulary. What makes a special science a science is that it contains lawful regularities stated in its proprietary vocabulary that ground explanations and counterfactuals. He is clear that what makes a special science regularity lawful is a fact that is irreducible to the laws and facts of fundamental physics (and other special sciences).3 That is, the lawfulness of special science regularities is a fact about the world as basic as and independent of the lawfulness of the laws of fundamental physics. Fodor’s view can be illustrated with the help of a souped up version of Laplace’s demon. The demon knows all the physical 2 It is not completely clear what either Fodor or Kim thinks the fundamental laws of physics are like but they seem to think of them as involving causal relations between types of local physical properties. As I later discuss this is not the way physicists think of fundamental laws. 3 Fodor identifies lawful regularities by the usual criteria of supporting counterfactuals and being confirmable by their instances. His view is that the laws of a higher level science are reducible to those of a more basic science only if the kinds of the higher level science can be identified with those of the more basic science. However, he sheds little light on what a kind is other than that they are properties that occur in laws. I discuss how to understand Fodor’s anti-reductionism in a companion to this paper “Why is There Anything Except Physics?” (Loewer 2008). 2 2 facts obtaining at all times and all the fundamental dynamical laws of physics, has perfect computational powers and also a “translation” manual connecting special science and physical vocabularies. The demon is thus able to tell which micro physical situations correspond to, for example, a philosophy conference and is able to determine which generalizations about philosophy conferences are true and which are false. It can do the same for all the special science. It will also be able to tell which special science regularities hold under counterfactual initial conditions and so which hold in all physically possible worlds (i.e. all the worlds at which the fundamental laws of physics obtain). But on Fodor’s view the demon will not be able to discern which regularities are laws.4 Because of this “blindness” the demon will be missing those counterfactuals and explanations that are underwritten by special science laws and so will not have an understanding of special science phenomena. Although the demon will be able to predict and explain the motions of elementary particles (or whatever entities are physically fundamental) from the state of the universe at any time and so could have predicted the stock market crash of 1929 it will not understand why it crashed. To do that it would need to know economics.5 Even without further clarifying (3) one can see that there is a tension among the three claims.6 According to (1) the subject matters of all the special sciences are ultimately constituted/realized by microphysical entities 4 See “Why There is Anything Except Physics?” for a defense of this way of understanding Fodor’s account of the relationship between special sciences and physics. 5 Kitcher (2001) makes this point with the example of “Arbuthnot’s regularity” that more males than females are born each year in London.. I discuss Kitcher’s argument later in this paper. 6 Kim certainly sees the tension although he develops it in terms of causation rather than laws. Since I think causation is not a fundamental physical notion I think this is a mistake. See Kim (2005 and 2007) and Loewer (2007 and 2008). 3 3 (fields, elementary particles, strings etc.) and events (changes in the positions and momenta of particles, changes in field values, etc.).7 Completeness of the dynamical microphysical laws means that the fundamental laws completely specify the dynamical evolution of the microphysical state of the universe (or of an isolated sub-system); i.e. for every time t, if the fundamental dynamical laws are deterministic and if S(t) is the state of isolated system Σ at t then S(t) and the laws determine a unique state S(t’) for Σ at t’; if the laws are probabilistic then, for every t, S(t) and the laws determine the chances at t of the evolution of future states.8 It follows from (1) and (2) that special science regularities (including probabilistic regularities) are made true by physical facts and laws. It is hard to resist the conclusion that those special science regularities that are lawful derive their status as laws from the fundamental laws of microphysics. Where else could it come from? A reduction of a special science law to fundamental physics would show how it is that the laws and facts of fundamental physics make certain special science regularities obtain and why some of them are laws. But, as Fodor observes successful reductions of special science laws to physics are, at best, very scarce.9 Although most biologists think that living organisms are 7 The natures of constitution and realization are complicated matters. Necessary conditions on constitution and realization are: A macro entity X is constituted by configuration C of micro entities (particles or fields related in such and such ways) at time t only if, given the fundamental laws, C’s existence at t metaphysically necessitates X’s existence at t. If X has property F at t then this instance of F is realized micro-physically only if there is a history of microphysical states that, given the laws, metaphysically necessitates that X has property F at t. 8 This characterization needs to be modified for relativistic space-times (in which there is no “state at a time”) and to take into account various other complications that are not relevant to the issues in this paper. 9 The best cases of reductions are laws of chemical combination to quantum mechanics and thermodynamics to classical or quantum mechanics. 4 4 constituted by microphysical entities obeying only microphysical laws no one has any idea of how, for example, the Hardy-Weinberg law (or any other biological law or psychological law) is made a law or even made true by physical facts and laws. Fodor thinks that nothing is more obvious than that there are special science laws. One of his often cited examples, Gresham’s law, says that if two kinds of money in circulation have the same denominational value but different intrinsic values, the money with higher intrinsic value will be hoarded and eventually driven out of circulation by the money with lesser intrinsic value. It apparently explains the hoarding of gold (i.e., “good money”) in Germany in the 1920s in terms of the introduction of quantities of paper money (i.e., “bad money”) into the German economy. Fodor has an argument that apparently shows that Gresham’s law doesn’t derive its lawfulness from microphysical laws. He observes that special science kinds, for example, money, are multiply and heterogeneously realized by physical kinds. Money can be made of no end of physically distinct materials (and also be electronically and psychologically realized). And he observes that special science laws are implemented by many distinct kinds of physical processes.