Real Dispositions in the Physical World

Real Dispositions in the Physical World

Ian J. Thompson

The role of dispositions in the physical world is considered. It is shown that not only can classical physics be reasonably construed as the discovery of real dispositions, but also quantum physics. This approach moreover allows a realistic understanding of quantum processes.

A distinction (note 1) is thus made between the 'Principal Cause' (that disposition which operates), and the 'Instrumental Cause' (that circumstance by means of which dispositions operate). Principal causes operate according to instrumental causes. Both are necessary for any action, for example, when a stone is let fall: the principal cause is the earth's gravitational attraction, and the instrumental cause is our action of letting go. Its hitting the ground is thus caused by our letting go, but only as an instrumental cause. Many common uses of 'cause' refer to instrumental causes rather than principal causes, as it is only in the instrumental sense that events can be said to be causes.

The next point to note is that dispositional properties can only be explained or reduced to other dispositions, not to entirely static or structural properties. That is, dispositions have a 'categorical irreducibility', as it is impossible to explain them away in terms of other categories such as space, time, form, process, material, property etc. For suppose that the exact shape and size of an object were known, the shapes and sizes of all its constituents, along with a list of these facts at every time. We would still know nothing about how or why the object would change with time or on interactions. Still less could we predict how it would respond to a new experimental test. In fact, if it and its parts had no dispositional properties, as Hume would argue, then we have his conclusion that any actions or changes (apart perhaps from uniform motion) would be entirely inexplicable: there would be nothing about the object that could lead to these changes rather than to any others.

A Powerful Theory of Causation

S. Mumford & R Anjum

There is, though, already an older tradition that acknowledges the dispositional nature of causation. Aquinas‟s philosophy of nature, according to Geach (1961), is one in which causes only tend towards their effects rather than necessitating them and the view presented in this paper is on that account neo-Aquinian.2 Many contemporary treatments of causation follow from Hume, however, as he was traditionally understood prior to the „New Hume‟ debate.Constant conjunction is there depicted as a necessary condition for causation having occurred. Dispositionalists have highlighted the weakness of constant conjunction, pointing out that there can be accidental cases that were not genuinely causal, and instead saw real dispositions as somehow imposing natural necessity on top of constant conjunction. We argue that a true dispositionalism, in contrast, is one in which a cause only tends towards its effect. For a general causal claim to be true, such as that smoking causes cancer, there need be no constant conjunction. And in particular causal claims, even if one cause indeed produced its effect, that doesn‟t mean it necessitated it. Something could have got in the way of the effect, even if it did not as a matter of fact.

Understanding irreducibly probabilistically constrained causation is not easy unless one accepts that it involves a dispositional connection that is neither entirely necessary nor entirely contingent. Our coin tends towards a 50:50 distribution, but in a sequence of trials there could be any distribution of heads and tails. We know that an actual 50:50 distribution is unlikely, especially when the number of trails is low. But we also know that if the number of trials is high then a distribution wildly at odds with an equal distribution is highly unlikely. There is a principle of probabilistic distribution that, applied to this case,says that the proportion of heads and tails will tend to 50:50 as the number of tosses tends to infinity; or, the higher the number of tosses then the closer to 50:50 the distribution is likely to be. This principle is appealing and yet we might wonder why it is true. Is it just some brute fact about the world or does it have a truthmaker? The powers theory offers a truthmaker for the principle. The coin has a tendency to land heads and tails with equal chance, a tendency which manifests itself over a sequence of trails. But this is only a disposition towards such a distribution. It does not necessitate it, as we know when we acknowledge that any actual distribution is possible for any sequence of tosses. Yet the distribution is not entirely contingent either, as we know when we acknowledge that distributions at variance widely from 50:50 are unlikely, proportionate to the number of trails.

The case of probabilistically constrained causation thus corroborates our account. It is noteworthy in so far as the account seems to accord entirely with what we already accept pre-theoretically to be the data of chancy causes.

Causation is Not Your Enemy

Ajum & Mumford

We argue in this paper that an aspect of causation has been misunderstood over a long period, especially in its connection with issues of modality, and this error has had a particularly significant and damaging influence on the direction of the free will debate. A tight connection has been drawn between causation and necessity, for instance, and this has been highly problematic to those seeking any kind of credible libertarian stance on free will. It is necessity that is the threat, we claim. Causation is seen as part of the problem of free will when really we should be looking to it as part of the solution.

In the traditional division between compatibilism and incompatibilism, we see that many philosophers have thought there to be a tension between free will and prior causes. They effectively thought of free will and causation as incompatible. We saw the reason why: they thought causation entailed necessity, which then entailed determinism. For instance, Libet’s (1985) neuroscientific experiments show at the most, if they show anything at all, that conscious decisions have prior causes. This impinges on the debate only if you think that free will is incompatible with prior causation.The real threat, we argued, was necessity because free will seems to be incompatible with determinism qua necessity (Mumford and Anjum 2014 also offer a defence of this kind of incompatibilism). This result is not alarming to any adherent of the dispositional modality for it is just an instance of the more general thesis that causation is incompatible with necessity, and thus with determinism qua causal necessity. Once that move has been made, the possibility is open for a re-appropriation of the term compatibilism. Our view is that free will is certainly compatible with causation. It is not something an agent needs to escape in order to be free. Indeed, how would freewill be possible other than through causation: allowing agents who are active, exercising causal powers in response to the worldly causes that affect them? The problem has been that many have thought the only way causation can work is through necessity and this has led them to assume that free will is threatened by causation per se. We have shown that it is not. Once causation and necessity are separated, you can see that causation is not your enemy.

A Powerful Theory of Causation

S. Mumford & R Anjum

Causation is Not Your Enemy

Ajum & Mumford

Free Will and Mental Powers

Niels van Miltenburg & Dawa Ometto

In this paper, we investigate how contemporary metaphysics of powers can further an understanding of agent-causal theories of free will. The recent upsurge of such ontologies of powers and the understanding of causation it affords promises to demystify the notion of an agent-causal power. However, as we argue pace (Mumford and Anjum in Analysis 74:20–25, 2013; Am Philos Q 52:1–12, 2015a), the very ubiquity of powers also poses a challenge to understanding in what sense exercises of an agent’s power to act could still be free—neither determined by external circumstances, nor random, but self-determined. To overcome this challenge, we must understand what distinguishes the power to act from ordinary powers. We suggest this difference lies in its rational nature, and argue that existing agent-causal accounts (e.g., O’Connor in Libertarian views: dualist and agent-causal theories, Oxford University Press, Oxford, 2002; Lowe in Personal agency: the metaphysics of mind and action, Oxford University Press, Oxford, 2013) fail to capture the sense in which the power to act is rational. A proper understanding, we argue, requires us to combine the recent idea that the power to act is a ‘two-way power’ (e.g., Steward in A metaphysics for freedom, Oxford University Press, Oxford, 2012b; Lowe (in: Groff, Greco (eds) Powers and capacities in philosophy: the new Aristotelianism, Routledge, New York, 2013) with the idea that it is intrinsically rational. We sketch the outlines of an original account that promises to do this. On this picture, what distinguishes the power to act is its special generality—the power to act, unlike ordinary powers, does not come with any one typical manifestation. We argue that this special generality can be understood to be a feature of the capacity to reason. Thus, we argue, an account of agent-causation that can further our understanding of free will requires us to recognize a specifically rational or mental variety of power.

Causal Constraint

S. Esser

Recall (see prior post here) that Mumford and Anjum analyze causation in terms of dispositions, or powers. These powers tend toward (dispose toward) their manifestations -- they do not necessitate them. Necessity is not the modality of causation. In addition, it is argued that dispositional modality is distinct from standard philosophical notions of possibility (logical or metaphysical possibility). Dispositional modality (dispositionality for short) does not involve “pure” possibility, since only certain manifestations are possible. In Chapter 8 of their book, the authors say: “Dispositionality…can be understood as a sort of selection function…that picks out a limited number of outcomes from all those that are merely possible.” Also: “The idea of a selection function is simply one that identifies a subset from a realm of possibilities. (p.189)”

In his book, Gregg Rosenberg introduced a model of causation which featured a notion which seems related to the idea of the selection function: this was a constraining function on the space of possibilities. Rosenberg, unhappy with both the Humean perspective on causation, as well as the theories of causal responsibility or causal production on offer, endeavored in chapter 9 of his book to strip down the notion of real causation to a bare minimum. This led him to the following notion of “causal significance”: “The causal significance of a thing is the constraint its existence adds to the space of possible ways the world could be…Causal significance shows causation to be an operator on a space of possibility. (p.150 emphasis original)” And: “It is a theory designed to understand how constraints propagate, so it explains how the actual world comes to be just a sliver of what could have been. (p.152)”

I say they seem like related notions, but constraint could be viewed as the negative image of selection. Selection picks out a few possibilities, while constraint rules out all of the others.

Causation, Dispositions, and Divine Action

Walter Schultz, PhD and Lisanne Winslow, PhD

This paper provides a conceptualization of causation and dispositions on the grounds of a new view of divine action. (We use ‘disposition’ generically to refer to what many are calling “active and passive causal powers.”While the latter terms are of medieval origin, the concept is from Aristotle (äõíÜìåéò, potentiality).1Dispositional explanations were commonplace in the eighteenth century and after the decline of positivism,the notions were revived in the twentieth-century by theists and non-theists alike.2) Even though theistic philosophers and metaphysically-interested theistic scientists agree that God created, sustains, and providentially governs the world, they disagree over how to understand divine sustaining action in relation to causation. By extension, they disagree regarding other concepts representing dynamic phenomena such as disposition and law of nature. At least since the 13thcentury the major competing theories among Christian theologians and philosophers have been (and remain) concurrentism and occasionalism. Concurrentism adopts Aristotle’s distinction between primary and secondary causation, holding that God (the primary cause)somehow co-operates with secondary causes. Occasionalism holds that the only real causes are God’s immediate, existence-conferring volitions, holding that apparent causes are really‘occasions’ for God to bring about effects.3 The secondary aim of this paper is to advance the debate by providing an alternative.

[Laird]

A Powerful Theory of Causation

S. Mumford & R Anjum

Cross-posting my response to this paper from a post in the Free will re-redux thread:

I was not convinced by their "argument against necessity", which runs as follows:

"Let us call a group of polygenic causes C1, ... Cn and assume that there is a case in which together they produce the effect E, the match lights. Nevertheless, it can be claimed, had all of C1, ... Cn occurred but also some interfering condition I been present, such as a gust of wind, then E might not have occurred. We are taking I to be a real natural or physical possibility, rather than a mere logical one. This shows that C1, ... Cn, although they caused E, were nevertheless consistent with E not occurring. Therefore, C1, ... Cn do not necessitate E, even if as a matter of fact they do cause E."

I wasn't convinced because I think it remains open to necessitarians to respond with this:

"Although we allow that adding I to C1...Cn could conceivably prevent the occurrence of E, and that in that sense, C1...Cn do not necessitate E, this situation nevertheless remains consistent with another, and more important (to us), sense in which a given combination of causes does necessitate whatever effect follows: that being the sense in which the contribution each causal power makes, and the manner in which these contributions are summed, is necessary.

"This is supported by your own framing, in which you write (bold emphasis added by us): 'That powers are pleiotropic means that they make the same contribution to any effect of which they are a cause. The same power always makes the same contribution, when it manifests'. In this context, 'always' is a synonym for 'necessarily', and since the 'vector addition' you describe by which powers add or subtract towards any final effect is the only possible means for arriving at that final effect, it, too, is in the sense we intend 'necessary'.

"Thus, although in one sense you have demonstrated that causes do not necessitate their effects, in a sense more important to us, and equally physical, you have not."

It's partly a matter of semantics, but not entirely.

That said, I think that the approach this paper describes of thinking of causality in terms of "dispositional powers" is useful (in the context of free will)

Cross-posting my response to this paper from a post in the Free will re-redux thread:

I was not convinced by their "argument against necessity", which runs as follows:

"Let us call a group of polygenic causes C1, ... Cn and assume that there is a case in which together they produce the effect E, the match lights. Nevertheless, it can be claimed, had all of C1, ... Cn occurred but also some interfering condition I been present, such as a gust of wind, then E might not have occurred. We are taking I to be a real natural or physical possibility, rather than a mere logical one. This shows that C1, ... Cn, although they caused E, were nevertheless consistent with E not occurring. Therefore, C1, ... Cn do not necessitate E, even if as a matter of fact they do cause E."

I wasn't convinced because I think it remains open to necessitarians to respond with this:

"Although we allow that adding I to C1...Cn could conceivably prevent the occurrence of E, and that in that sense, C1...Cn do not necessitate E, this situation nevertheless remains consistent with another, and more important (to us), sense in which a given combination of causes does necessitate whatever effect follows: that being the sense in which the contribution each causal power makes, and the manner in which these contributions are summed, is necessary.

"This is supported by your own framing, in which you write (bold emphasis added by us): 'That powers are pleiotropic means that they make the same contribution to any effect of which they are a cause. The same power always makes the same contribution, when it manifests'. In this context, 'always' is a synonym for 'necessarily', and since the 'vector addition' you describe by which powers add or subtract towards any final effect is the only possible means for arriving at that final effect, it, too, is in the sense we intend 'necessary'.

"Thus, although in one sense you have demonstrated that causes do not necessitate their effects, in a sense more important to us, and equally physical, you have not."

It's partly a matter of semantics, but not entirely.

That said, I think that the approach this paper describes of thinking of causality in terms of "dispositional powers" is useful (in the context of free will)

Would you mind bringing in an example, say a match being lit upon striking? I think it might help me see what you mean.

[Laird]

Would you mind bringing in an example, say a match being lit upon striking? I think it might help me see what you mean.

Well, C1...Cn were already the example of a match being lit upon striking. The authors say: this combination of causes does not necessitate E, the effect which is the lighting of the match, because the addition of I could prevent E, and thus there is a scenario in which the combination C1...Cn does not cause E.

I'm suggesting the necessitarians might respond: fine, but taking C1...Cn without adding I, this combination of causes could be seen to necessitate E in the sense that (given the way in which the paper's authors seem to frame the situation), (1) each contributing power of each of C1...Cn is necessitated (as the authors say: each power always makes the same contribution to any effect, with "always" being synonymous in this context with "necessarily"), and (2) the process of summing up the powers of C1...Cn (to arrive at E) is the only one possible, and thus "determinate", i.e., in a sense, necessary. Given (1) and (2), there is in a sense no possibility (without I) of any outcome other than E, and thus C1...Cn (again: without I) do in a sense necessitate E.

Now, it might be objected by the paper's authors: but the stipulation "without I" avoids our whole argument! You simply can't make that stipulation!

And the necessitarians might then respond: but we have never contested that if a set of causes changes (such as by the addition of I), the effect might change! Our argument for causal necessity has only ever assumed that an effect is necessitated by the set of causes as they are.

And I think that that would be a reasonable response. Do you?

Now, it might be objected by the paper's authors: but the stipulation "without I" avoids our whole argument! You simply can't make that stipulation!

And the necessitarians might then respond: but we have never contested that if a set of causes changes (such as by the addition of I), the effect might change! Our argument for causal necessity has only ever assumed that an effect is necessitated by the set of causes as they are.

And I think that that would be a reasonable response. Do you?

But doesn't the problem of diffusing the notion of cause still occur? We still go from the focused explanation of lighting a match due to, say, combustibility and friction of specific elements and now have to include absence/presence of other causes?

Don't get me wrong, I agree that this idea of Necessity vs Disposition is best understood by stable indeterminisms like half-lives. But I do they think they are on to something relevant in that only by distinguishing the direct sources of a cause-effect relation, as in the primary contributors of causal dispositions, are we able to do science and take advantage of its applications.

(After all the manifestations of causal powers can still result in deterministic causal sequences, just ones that can at least hypothetically be interrupted.)