What about non-actual individuals? Suppose Pope John Paul II had had children. Might any of them have accepted a $300,000 bribe, if offered one? Molina and Plantinga suppose that this question must have an answer (despite the difficulty of our finding it out). Molina supposed that even merely possible individuals can have habitudes, grounding the truth of conditional propositions.
Alvin Plantinga (1974), however, argues that only existing things can have properties. Instead, he makes use of the corresponding haecceities or thisnesses. According to Plantinga, each actually existing thing, like Socrates, has its own unique thisness. Socrates is unique in having the property of Socrateity, the property of being Socrates (that very man). Nothing else could possibly have had that property. Since Socrates might not have existed, this property of Socrateity might have had no actual instances. It might have been like the property of being a unicorn. Since there could have been things that don't actually exist, Plantinga infers that there are many thisnesses that lack their corresponding instance in the actual world. For example, there might be an un-actualized thisness, which, had it been actualized, would have been an child of Pope John Paul II, and which would have been accompanied or co-instantiated by the habitude of being the sort of person who would have accepted a $300,000 bribe if offered one. (We will discuss haecceities again in more detail in both Chapters 9 and 16.)
Plantinga's neo-Molinist account seems to be quite a lot to swallow—we have to accept both un-actualized thisnesses and the peculiar, simple, and extrinsic habitude properties. Perhaps that is the best metaphysical account of counterfactual conditionals, but it would seem reasonable to look hard for an alternative with fewer somewhat mysterious and sui generis entities and properties. Another way to read Plantinga is as embracing Hypotheticalism but denying that (fundamental) hypothetical truths have a ground at all. On this view, you don't embrace habitudes and ground counterfactual facts in them; instead, you just keep asserting counterfactuals (“what would have had that haecceity would have done A, had such and such occurred”)!
4.3 Anti-Hypotheticalism and Laws of Nature
Let's turn, then, to Anti-Hypotheticalism, the view that the truth of conditionals is conceptually or logically grounded in non-conditional facts. As we've seen, the evaluation of conditionals seems to turn on two sorts of facts about the actual world: the laws of nature, and the true propositions that are co-tenable with the conditional's antecedent. If we knew these two sets of truths, we could define which antecedent-verifying worlds are ‘closest’ in the relevant sense to the actual world.7
Here's a simple proposal for identifying the co-tenable truths, offered by Frank Jackson (1987). Let's suppose that the antecedent of the conditional refers either to the non-occurrence of some specific, actual event or to the occurrence of some specific, counterfactual event. In either case, we can identify a specific time and place that is uniquely relevant to the actual falsity of the antecedent. The contents of this antecedent-falsifying location have some place in the actual network of causes and effects. Jackson proposes that any truth describing an event or state occurring entirely before the antecedent-falsifying location is co-tenable with the antecedent, as is any truth describing an event or state simultaneous with or shortly after the location, so long as this event or state is not causally posterior (an effect or effect of an effect, etc.) to anything in the antecedent-falsifying location. Roughly speaking, when we evaluate the counterfactual conditional (p q), we can treat as co-tenable with p any truth pertaining to a time before the time at which p was falsified, and any truth that is not causally “downstream” from ∼p. Here are a couple of examples:
(18) If Curley had been offered a $300,000 bribe last Monday morning, he would have accepted it.
(19) If the circuit breaker had failed at the time of the power surge this afternoon, a fire would have resulted.
In conditionals like these, some counterfactual event or condition is supposed to occur at some precise time. In evaluating the conditionals, we treat as fixed the actual conditions of the world up to the time involved in the antecedent. We then add the counterfactual condition to that set of actual conditions, and we suppose that the world would subsequently evolve according to the actual laws of nature. Thus, we take Curley's character in the actual world at 10 a.m. last Monday (not his character at any earlier or later time); we add the event of the bribe, and then we apply what we know about the laws of human psychology to predict how he would have responded. Similarly, we keep the condition of the circuit and the circuit breaker at the time of the power surge as fixed. We also assume that the power surge occurs when and how it actually occurred, and then we add the supposition that the circuit breaker fails. We use what we know about the laws of physics to predict the subsequent behavior of the system. There may be other conditionals that cannot be evaluated in this way (consider Lewis's example: ‘if kangaroos had no tails, they would topple over’), but this class seems to be of special and central importance.
We will take up questions about the direction of time and of causality in later chapters. For present purposes, let's pretend that we can always determine the co-tenable truths relevant to a counterfactual conditional and focus exclusively on the role of laws of nature in supporting such conditionals.
One possibility, then, is that the truth of counterfactual conditionals is wholly grounded in truths about the laws of nature.
What are the laws of nature? To be a law of nature is not simply to be a true universal generalization. In fact, being a true universal generalization is neither necessary nor sufficient for being a law of nature. It is not sufficient because true universal generalizations like ‘all the coins in my pocket are bronze’ are pretty obviously not laws of nature. But even more interestingly, laws need not hold without exception. Some laws are “oaken” rather than “iron,” to use David Armstrong's distinction. Laws of biology and economics, for example, seem to admit of exceptions. For example, deficit spending in a recession stimulates employment, but this effect can be neutralized by a number of factors, including anxiety about the future on the part of investors and business managers. Birds fly, but ostriches, penguins, and dodos do not. Thus, being a statement corresponding to a true universal generalization is not even a necessary condition for being a law of nature.
Are the laws of nature metaphysically fundamental or are they grounded in still more basic truths? If the laws of nature are derived truths, what do they derive from? If laws are not fundamental, there are at least three possibilities: (i) the laws of nature are grounded in the truths of counterfactual conditionals, (ii) they are grounded in truths about the powers and dispositions of particular things, or (iii) they are grounded in other truths about particular things, truths having nothing to do with powers and dispositions.
4.2T Nomic Fundamentalism. Some truths about the laws of nature are fundamental.
4.2A Nomic Reductionism. No truths about the laws of nature are fundamental.
What would the world be like if the laws of nature were fundamental? Such a view has been defended by Fred Dretske (1977), David M. Armstrong (1983), and Michael Tooley (1977). The Dretske/Armstrong/Tooley, or DAT, account of laws holds that a law consists in a special, irreducible relation of nomological necessity connecting one or more properties or universals. For example, if it were a law of nature that water freezes at 0°C, then this law would consist in a special nomic link between the property of being water at 0°C and that of becoming frozen. We will look at the DAT account of laws in Section 5.1.
Laws could, however, be reduced to counterfactuals. For instance, we could define a law of nature as a truth that would remain true under any antecedent that does not falsify any law of nature or any law of logic or mathematics. Of course, put this way, the definition would be circular. The circularity can be eliminated by defining the laws of nature as the smallest set of truths T (strictly larger than the set of logical and mathematical truths) such that every member of T would remain true under any antecedent not
falsifying any member of T (see Lange 2004). However, such a reduction would be of interest only to Hypotheticalists, and not to Anti-Hypotheticalists, since the latter assumes that the truth of conditionals is grounded in that of the laws, and not vice versa. We will look take another look at a strong version of Hypotheticalism in Section 4.4.
Could the laws of nature be grounded in the powers and dispositions of particulars? The law that ice freezes at 0° C could be grounded in the passive power of water to freeze when its temperature is lowered to 0° C. Any causal law of nature could be expressed in terms of all of the instances of one kind of thing A having the active power to affect any instances of a second kind of thing B when the two are in a certain relation R, producing the result that the second thing takes on a new characteristic C. The law could be taken as simply expressing the fact that all A's have the active power of producing effect C in any R-related B or that all B's have the passive power of being made C by any R- related A.
Powers and dispositions seem to come in five varieties: active powers, passive powers, immanent powers, resultants, and tendencies.
Def D4.1 Active Power. A property P is an active power if and only if, necessarily, whenever a thing has P there is the possibility of its producing a specific kind of effect E on some other thing under specifiable conditions by virtue of having P.
Def D4.2 Passive Power. A property P is a passive power if and only if, necessarily, whenever a thing has P there is the possibility of its being affected in some specific way E by some other thing under specifiable conditions by virtue of having P.
Def D4.3 Immanent Power. A property P is an immanent power if and only if, necessarily, whenever a thing has P there is possibility of its producing some intrinsic change in itself under specifiable conditions by virtue of having P.
Def D4.4 Resultant. A property P is a resultant if and only if, necessarily, whenever a thing x has P at t, there is some earlier time t′ and some passive or immanent power M such that x has P at t by virtue of its having exercised M at t′.
Def D4.5 Tendency. A property P is a tendency if and only if, necessarily, whenever a thing has P there is a certain likelihood or propensity for it to exercise one of its active or immanent powers under specifiable circumstances by virtue of having P.
We will use the terms ‘power’ and ‘disposition’ interchangeably as general terms for any property of any of these five kinds.
We can now ask: are truths about the powers of things fundamental or derived?
4.3T Power Fundamentalism. Some truths about the powers of particular things are fundamental.
4.3A Power Reductionism. No truths about powers are fundamental.
If powers are not fundamental, there are two plausible accounts of how they can be derived from other truths. They are derivable either from truths about the laws of nature or from truths about counterfactual conditionals.
There are thus four attractive positions: Strong Hypotheticalism (conditionals are fundamental, but not powers or laws), Strong Nomism (laws are fundamental, but not powers or conditionals), Strong Powerism (powers are fundamental, but not laws or conditionals) and Neo-Humeism (none of the three are fundamental).
4.4T Neo-Humeism. None of the truths of counterfactual conditionals and none of the truths about laws of nature or about the powers of particulars are fundamental.
4.4A Anti-Humeism. Some of the truths of counterfactual conditionals and none of the truths about laws of nature or about the powers of particulars are fundamental.
4.4A.1 Strong Hypotheticalism. Some of the truths of counterfactual conditionals are fundamental, but no truths about particular powers or the laws of nature are fundamental.
4.4A.2 Strong Nomism. Some of the truths about laws of nature are fundamental, but no truths about particular powers nor any of the truths of counterfactual conditionals are fundamental.
4.4A.3 Strong Powerism. Some of the truths about the powers of particular things are fundamental, but no truths about the laws of nature, nor any of the truths of counterfactual conditionals, are fundamental.
Here is a diagram illustrating the difference between Neo-Humeism and Strong Powerism:
Figure 4.1 Comparing Powerism and Neo-Humeism
Strong Hypotheticalism and Strong Nomism differ from Powerism simply by shifting either subjunctive conditionals or laws of nature from the upper, dependent position to the base. The Neo-Humeist view is unique in having a simpler base (only qualities and spacetime) and by involving two steps of reduction: reducing laws to the “Humean mosaic” of qualities in spacetime, and then reducing powers, causal connections, and subjunctive conditionals to the laws of nature (together with the mosaic).
If we were to reject all four positions, there would be only two options. First, we could suppose (along with Quine) that there are (strictly speaking) no truths of any kind in this area, no true conditionals, laws of nature or attributions of powers. Second, we could suppose that two or more of the classes of propositions have their own, distinctive truthmakers. The first option is a radical departure from science and common sense, and the second involves apparently redundant or superfluous truthmakers.
4.4 Strong Hypotheticalism: Counterfactual Accounts of Powers and Dispositions
Strong Hypotheticalists hold that the truths of counterfactual conditionals are fundamental, and that truths about the laws of nature and of powers and dispositions are reducible to them. We are not going to question the reducibility of laws to conditionals, but we do want to take a close look at the claim that powers can be reduced to conditional truths:
Let's consider fragility, a paradigm case of a dispositional property or power. Fragility is an example of what we have called a ‘passive power’, the power to be affected in a certain way by certain things. Strong Hypotheticalists are committed to the thesis that all facts about powers are wholly grounded in facts about conditionals:
Reduction of Powers to Conditionals. Necessarily, for any x, if x has the B/A power (the power to bring about B when in state A), then x's having the B/A power is always wholly grounded in the truth of the subjunctive conditional: if x were in A, x would B.
Plausibly, the attribution of fragility to a thing x is grounded in the fact that x would break if struck. The very meaning of ‘fragility’ is tied to the connection between breaking and being struck. Fragility is the breaking/being-struck power or disposition. Reduction of Powers to Conditionals asserts that a thing x's having the B/A power consists in the appropriate conditional proposition's being true—namely, the proposition that x would B if A. If this is so, then the truth of the corresponding conditional should be both necessary and sufficient for the truth of the predication of fragility to x.
It is plausible to suppose that if the truth of one proposition p is necessarily wholly grounded in the truth of another proposition q, then the two propositions are metaphysically equivalent (i.e., each is a necessary and sufficient condition for the other):
Principle of Metaphysics (PMeta) 1 The Necessary and Sufficient Condition Test for Necessary Grounding. If the truth of a proposition p is necessarily wholly grounded in the truth of proposition q, then the truth of q is a metaphysically necessary and sufficient condition for the truth of p.
This principle of metaphysics would be true if thesis 3.9T, the Grounding-Entailiment Entailment thesis, is true:
3.9T Grounding-Entailment Entailment. Necessarily, if the fact that p grounds the fact that q, then p metaphysically entails q (i.e., necessarily if p is true, then q is true).
In Chapter 3, we found some reasons both for and against 3.9T. If we end up rejecting 3.9T, then we should replace the Necessary and Sufficient Condition Test for Necessary Grounding with the weaker Necessary Condition test:
Principle of Metaphysics (PMeta) 1.1 The Necessary Condition Test for Necessary Grounding. If the truth of a proposition p is necessarily wholly grounded in the truth of proposition q, then the truth of q is a metaphysically necessary condition for the truth of p.
C.B. Martin (1994) has produced some examples of so-called ‘finkish dispositions’ that demonstrate that the truth of the ‘if A then B’ counterfactual conditional is neither necessary nor sufficient for the truth of the attribution of the B/A disposition (see also Lewis 1997, Lowe 2010).
Here is an example of a finkish disposition which shows that the truth of the ‘if A then B’ counterfactual is not necessary for the truth of the attribution of the B/A disposition. Suppose there was a genius mad scientist who was obsessed with a particular vase. This vase is especially fragile because it's made of extremely thin blown glass. But our genius mad scientist's obsession with this vase caused him to invest his energies in producing a device of the following sort: if ever the vase is about to be struck, this device instantaneously alters the chemical structure of the vase, rendering it unbreakable. The vase's fragility is “finkish” in that it cannot manifest itself in the vase's breaking given the presence of the device. The device is, in that sense, a finking mechanism. In this case, we have something that is fragile, even though it is false that it would break if struck. The truth of the conditional is not necessary for the truth of the attribution of the B/A disposition.
Conversely, suppose we start with a vase that is not fragile. But this time there is a finking mechanism which instantaneously alters its microstructure, rendering it breakable, whenever it is about to be struck. In this case, we have something that is not fragile, even though it is true that it would break if struck. This shows that the truth of the ‘if A then B’ counterfactual is not sufficient for the truth of the attribution of the B/A disposition.
The Atlas of Reality Page 15
