Free Agents as Cause Daniel von Wachter January 28, 2009 This is a preprint version of: Wachter, Daniel von, 2003, "Free Agents as Cause," On Human Persons, ed. K. Petrus. Frankfurt: Ontos Verlag, 183-194. The dilemma of free will is that if actions are caused deterministically, then they are not free, and if they are not caused deterministically then they are not free either because then they happen by chance and are not up to the agent. I shall propose a conception of free will that solves this dilemma. It may seem to many metaphysically more extravagant than other conceptions but I shall suggest that this should not deter us. However, I shall not undertake here to argue that there really are beings with free will; this would be a different project. Here I shall only discuss what free actions would be like. Imagine a tidal wave at time t2 that was caused by an earthquake in the sea at time t1. There was a causal process, described by laws of nature, leading from the earthquake to the tidal wave. The tidal wave was a part of an ongoing causal process and was a result of this process. Let me define a few terms 1 related to causal processes. An event that includes everything that belongs to a process at a certain time (instant or period) when the process is going on I call a stage of the process. An event that is a stage or a part of a stage of a process I call a part of the process. A stage or a part of a stage of a causal process is a cause of every later stage of the process. A stage of a causal process is the complete cause of every later stage of the process. A cause of this type, i.e. a cause that is a part of a causal process of which its effect is a later part, I call an event cause, in order to distinguish it from what some authors have called an 'agent cause'. If an action is a part of an ongoing causal process and a result of this process, then, in an interesting sense of 'free', the action is not free, even if the agent feels free. Other authors define what is essentially the same concept of freedom by saying that free agents 'are not causally necessitated to do the actions which they do by brain-events or any other events' (Swinburne 1997, 231), or by saying that a free action is not caused by a preceding 'sufficient causal condition' (Chisholm 1976, 202). This kind of [|184] freedom is usually called libertarian freedom. We can, of course, form also other concepts of freedom, compatibilist freedom, which do not require that a free action is not the result of ongoing causal processes. For each concept of freedom we can form we can inquire whether there are beings that have such freedom. Further, one can argue that one concept of freedom is more similar to our usual concept of freedom and more relevant for questions of responsibility and guilt than others. To many it seems that if someone was caused to do what he did and if he could not have prevented the causes of his action to cause him to act in the way he did, then he is not responsible for his action. However, here I shall not discuss 2 for which concepts of freedom there are beings with that kind of freedom, and I shall not discuss which concept of freedom is how adequate. I only want to discuss what libertarian free actions would be like. Assume somebody freely raised his arm. There was a causal process leading to the rising of the arm, involving events in the muscles, nerves, etc. I call this the action process. As the action was free, it does not go back infinitely, it had a beginning. I call the first stage of the action process the initial event. It was not wholly caused by a preceding event. The initial event may have been a complex event, some parts of which were caused by preceding events. But, if the action was free, then at least an event that is a part of the initial event was not caused by preceding events. I call this event that was not caused by preceding events the initiating event or choice event. How and why did the initiating event occur? According to the assumption that the action was free, it was not fully caused by preceding events. It is often suggested that an action is free if, and only if, there is 'indeterminacy' at a certain point. Clarke holds that the decision has to come about inderministically: 'When a decision is freely made [...] there remained until the making of that decision a genuine chance that the agent would not make that decision.' (Clarke 2000, 21) Others hold that that in a free action the decision is caused deterministically but the process of deliberation leading to the decision is indeterministic (Dennett 1978; Fischer and Ravizza 1992; Mele 1995). It is true that an action's involving an indeterministic process makes it true that, before the action occurred, it was possible that another action would occur instead of the one that did occur. But this is not what we are getting at when we 3 say that a free agent 'could have done otherwise'. The trouble is that if it is a matter of indeterminacy which action occurs then it is not up to the agent what he does. An action that occurs by chance is not a free action because the agent lacks control over which action occurs. If an action is the result of an indeterministic process, then the agent has as little control over it as an agent has over an action that occurs as the result of a deterministic process. We are stuck at the second horn of the dilemma of free will. Can we avoid it? If the action was free, then the initiating event was not caused deterministically, it was not uncaused, and it was not caused indeterministically. Is there another way how an event can come about? I suggest that there is another way. As the action was free, the action process had a beginning whose occurrence was due to the agent. If you trace back the causes of the action result, the rising of the arm, you reach a stage of the action process a part of which, the initiating event, did not have a preceding cause. It had neither a deterministic nor an indeterministic preceding cause. Its occurrence was due to the agent. The agent made an event pop up that initiated the action process. This initiating event, together with other events, caused the later stages of the action process and the action result. [|185] We can call the initiating event also 'choice' or 'choice event'. A choice event is an event that has no preceding cause and whose occurrence is due to an agent. We can say that the event is the agent's choice, or that it occurs as the agent's choice. A free agent is somebody who can initiate causal processes by doing something for a reason and with an intention. However, the agent need not know what the choice event is and he need not know all the stages of the action process. Human 4 agents (I assume for the sake of the argument that they are free) never know all the stages of the action process when they move parts of their bodies. If somebody raises his arm, then the rising of his arm is caused by certain brain events, but the intention governing the action is not about all the events that cause the action result. The agent does not do anything in or with his brain in order to raise his arm; he does not even know what brain events cause the rising. When he tries to raise his arm a choice event occurs that causes the rising of his arm, without the agent knowing all the events that cause the rising of the arm. What is needed for successful free action is that the agent knows what he has to try to do in order to achieve what, and that when he tries a choice event occurs that causes the intended result. With choice events the dilemma of free action is solved. Free actions are neither caused deterministically nor are they uncaused or indeterministically caused. Choice events are the third way that avoids both horns of the dilemma. What are the choice events in human free action? What answer one will give to this question partly depends on what view one takes on the mind body problem. A materialist will argue that choice events are certain physical events, presumably brain events. A dualist may hold that they are non-physical events of a certain kind. In either case, one promising candidate for choice events are tryings. Let me illustrate. Imagine you want to drink a cup of tea. You take the handle of the cup in order to lift it. But due to an illness of yours your arm is paralysed and does not do what you want. You try in vain to lift your arm. Then you try again. This time you are successful: your arm obeys your command and rises. The mental event that occurred when you first tried to raise 5 your arm, which is described by 'I tried to raise my arm', is an example of a trying. An exactly similar event occurred presumably when you raised your arm successfully. As I use the term, there are successful as well as unsuccessful tryings. Tryings are mental events of the kind that occur when someone undertakes an action.1 Perhaps all choice events in human actions are tryings. A dualist may take tryings to be non-physical events, a materialist will take them to be identical with certain physical events (or he will say that for each trying a physical event fulfils its causal role). However, we do not need to answer the question which events are choice events here. My thesis is [|186] just that the action process in a free action involves an event that has no preceding cause and whose occurrence is due to the agent. 1 Is a choice event caused by the agent? Often when a choice event occurs, another choice event could have occurred instead, or no choice event at all. Although choice events are not caused by earlier events, they do not occur by accident. Rather, they occur because agents choose. Should we then say that they are not caused at all or should we say that they are caused, but not by other events but by agents. Whether we say that a choice event is caused by the agent is mainly a question of terminology. To say that they are caused by agents may be adequate and useful as long as 1 Swinburne (1997, 95) uses besides 'tryings' also the term 'purposings'. Chisholm (1976, 201) uses 'undertakings'. 6 we are clear about the differences between how a choice event comes about and how an event caused by a preceding event comes about. Let me state these differences again. Where an event caused another event the one event was part of a process that led to the other event. A person and his choice event, however, are not connected through a causal process. A choice event occurs because the agent makes a certain choice, and this bears little resemblance to the way how an event causes another event. Further, whereas an event that causes an event is always earlier than the caused event, the person is in no clear sense earlier than the choice event. There is nothing about the person which takes place at a certain time before the choice event which we could identify as the cause of the choice event. A choice event has no preceding cause. All this counts against saying that choice events are caused by agents. On the other hand, it is quite in line with common talk as well as with the philosophical tradition to say of the result of a free action that it is caused by the agent. Furthermore, where a choice event occurred usually another choice event could have occurred instead (or none at all). And that the one rather than the other occurred was due to the agent. Now, something to which it is due that the world carries on in one way rather than in another is fittingly called cause of that which happens due to its activity. That counts in favour of saying that a choice event is caused by the agent. Further, we commonly say about the result of an action that it is caused by the agent. If you raise your arm, you are rightly called the cause of your arm's rising. You brought about your arm's rising, and this is synonymous to saying that you caused your arm's rising. Likewise, there is no reason why we should not say of a choice event that it was 7 brought about, or 'caused', by the agent. I conclude that it is adequate to say of a choice event that it is caused by the agent. Further, it is adequate to say of events that are effects of a choice event, that they are caused by the agent. We can say that a person was a cause of events that were caused by [|187] a choice event that occurred through his choice. Usually the context will make clear whether with a statement of the form 'x caused y' it is meant that y was, or was the effect of, a choice event that occurred in virtue of x's choice, or whether x was a part of a causal process that led to y. Where one wants to make clear that y occurred because of x's choice, one can say that x was the agent cause of y, or that y was caused through x's action. Where one wants to make clear that y occurred as the result of a causal process of which x was an earlier part, one can say that x was an event cause of y. However, I am not claiming that agent causation and event causation are somehow the very same relation,2 in the one case relating an agent with an event and in the other case relating an event with an event. 2 Agent causation Is my proposal in line with Chisholm's theory of 'agent causation'?3 Surprisingly not. I shall now show that Chisholm's 2 Randolph Clarke proposes an account of agent causation of the kind I reject here. He writes: 'The relation that obtains between cause and effect in an instance of agent causation is the very same relation that obtains between cause and effect in an instance of event causation.' (Clarke 1996, 21) 3 (Chisholm 1976; 1976, ch. 2). Very similar is Swinburne's theory: (Swinburne 1997, 89-96 ; 1994, 56-62 ; 1997, 87-90). The objections I 8 theory does not help to solve the dilemma of free action, and that Chisholm confuses semantical with metaphysical issues. Chisholm holds that there is besides event causation another kind of causation, namely agent causation. The centre piece of his theory is the concept of undertaking, by which he means what I have called 'trying'. About an event that results from a successful undertaking Chisholm says that the agent 'contributed causally to' it (Chisholm 1976, 205); the agent is the cause of it. So if you raise your arm, then you are the cause of your arm's rising, which means the same as that you are contributing causally to your arm's rising. One might think then that Chisholm's 'undertakings' are what I have called 'choice events'. In order to solve the dilemma of free action we need to assume that there is a way how an event may come about other than through event causation or indeterministic processes. One should think that those who hold that there is agent causation do so in order to solve the dilemma of free action by introducing agent causation as the special way how an event comes about in a free action. Why else would one assume that there is besides agent causation another kind of causation? However, Chisholm's theory fails to solve the dilemma of free action. A free action, for Chisholm (1976, 202), is an action that involves an undertaking for which there is no preceding 'sufficient causal condition'. But, according to Chisholm, also non-free actions [|188] involve undertakings and hence agent causation (whereas I have argued that only free actions involve raise below apply equally to Swinburne's theory. Other authors who have proposed agent causation are (Reid 1788), (Taylor 1966, chs. 8 & 9), (O'Connor 2000). 9 what I call choice events and what I call agent causation). The difference is only that in a non-free action the undertaking has a preceding sufficient event cause. I have two objections. First, Chisholm rightly says that in a free action the undertaking has no preceding sufficient cause, but he does not specify how it comes about instead. He fails to consider the case where it occurs by chance, as the result of an indeterministic process. Surely if an undertaking occurs by chance, then the agent has no control over it, the action is not up to the agent, therefore the action is not free in the sense in question. But according to Chisholm's definition of a free action it is a free action. In my definition of a choice event I therefore not only say that a choice event has no event cause but additionally that its occurrence is due to the agent, the agent makes in pop up. So Chisholm's definition of a free action fails to exclude the case where an undertaking occurs by chance and not under the control of the agent.4 Second, to Chisholm's claim that there is agent causation in non-free actions I object that we have no reason to assume that 4 Johann Christian Marek pointed out to me that Chisholm has addressed this objection in his (1979). There he answers the question what an undertaking in a free action has that an uncaused physiological event does not have as follows: 'What it has is this: it is the agent's undertaking. To put the matter somewhat loosely, it is a state of affairs that involves the agent himself. We can describe the physiological events in my brain without using expressions that refer to any person. But the property of undertaking – like that of thinking or believing – is a property that can be had only by persons.' (363f) I do not find this convincing because saying that it is the agent's undertaking does not rule out that it is a chance event whose occurrence is not up to the agent. It only says that the undertaking occurs in Jones's mind rather than in Miller's. 10 in non-free actions there is another kind of causation besides event causation involved. Assume your raising your arm is fully caused by preceding events, for example through a machine that is connected to your brain. Chisholm would still say that your arm's rising is caused by you – but surely the full truth is that your trying to raise your arm as well as your arm's rising was caused by nothing but preceding events. Contra Chisholm, there is no extra kind of causation involved in non-free actions.5 Why does Chisholm hold that there is an extra kind of causation involved in non-free actions? The reason is that Chisholm by claiming that there is agent causation means something different from what one should think he means. He does not mean that when Smith raises his arm the way how the arm's rising comes about is dissimilar to the way how an explosion comes about that is caused by a spark. (Whereas I hold that the way [|189] how a choice event comes about is dissimilar to the way how an explosion comes about.) His claim that there is irreducible agent causation is in fact not a claim about action but about certain statements describing actions. It is a child of the linguistic turn. This becomes clear in the following passage. The philosophical question is not – or at least it shouldn't be – the question whether or not there is 'agent causation'. The philosophical question should be, rather, the question whether 'agent causation' is reducible to 'event causation'. Thus, for 5In earlier writings Chisholm defended a theory of agent causation that is more similar to mine. There he postulated an event 'which is caused not by any other event, but by the agent' (Chisholm 1964, 54) (cf. Chisholm 1966). This seems to be getting at what I have called a choice event. 11 example, if we have good reason for believing that Jones did kill his uncle, then the philosophical question about Jones as cause would be: Can we express the statement 'Jones killed his uncle' without loss of meaning into a set of statements in which only events are said to be causes and in which Jones himself is not said to be the source of any activity? And can we do this without being left with any residue of agent causation – that is, without being left with some such statement as 'Jones raised his arm' wherein Jones once again plays the role of cause or partial cause of a certain event? (Chisholm 1978, 622f, quoted in O'Connor 2000, 64) So by his claim that there is agent causation Chisholm does not mean that there is something like what I have called choice events, he only means that statements like 'Jones killed his uncle' cannot be transformed into statements of a different kind. I suggest that investigating statements is the wrong method for finding out whether there is agent causation. Chisholm's mistake is that he tries to answer a metaphysical question just by answering semantical questions. That the statement 'Jones killed his uncle' cannot be transformed into a statement of a different type does not mean that Jones's action involved a kind of causation different from event causation. 3 Peter van Inwagen's mystery objection against agent causation Peter van Inwagen, in his article 'Free Will Remains a Mystery' (2000), has claimed that free will 'undeniably exists' but that 12 there is no way out of the free will dilemma and that free will is hence a mystery. He argues that agent causation offers no remedy; it 'is entirely irrelevant to the problem of free will' (van Inwagen 2000, 11). He comes to this conclusion because of the following thought experiment. Imagine Alice being in a situation where she has a choice between doing A and doing B at time t2. Before the decision, e.g. one minute before, at t1, it was undetermined whether she would do A or B. Suppose she does A. Now suppose that God 'caused the universe to revert to precisely its state one minute before Alice' did A, i.e. to its state at t1. (p. 14) Then 'let things go forward again'. Again it is undetermined what she will do. She might do A, she might do B. Suppose she does B. 'Now let us suppose that God a thousand times caused the universe to revert to exactly the state it was in at t1. [...] What would have happened?' (p. 14). Probably Alice will sometimes do A and sometimes B. [|190] Van Inwagen suggests that the frequency of her doing A would converge: 'As the number of "replays" increases, we observers shall – almost certainly – observe the ratio of the outcome' A to the outcome B 'settling down to, converging on, some value'. Van Inwagen suggests further that we should infer from this that it is 'simply a matter of chance' (p. 15) what Alice does. 'Is it not true that as we watch the number of replays increase, we shall become convinced that what will happen in the next replay is a matter of chance?' If it is a matter of chance what she does then she is not able to choose between A and B. It is not up to her what she does. 'If one confronts a choice between A and B and it is a matter of chance whether one will choose A or B, how can it be that one is able to choose A?' (p. 17) Van Inwagen believes that 'there is something wrong with 13 the argument' (p. 18), but he has no views about what is wrong with it. What he wants to show is mainly that the concept of agent causation offers no remedy here, that if it were of any use it would offer remedy, and that therefore it is of no use. 'The concept of agent causation cannot be used to undermine the intuitive plausibility of this argument.' (p.16) He points out that even if we were to assume that Alice is an agent cause, given many repetitions of the situation of decision, the ratio between her doing A and her doing B would converge. Therefore, so van Inwagen argues, we should still assume that it is a matter of chance what she does, and hence she does not act freely. I object that it is not true that in any case, if the ratio between Alice's decisions to do A and decisions to do B were to converge, we should accept that Alice's acting is a mere matter of chance. Whether the outcome of van Inwagen's experiment counts against the assumption that Alice has free will depends on whether we should expect a different outcome in the case of Alice having free will. What sort of outcome should we expect on the assumption that Alice is acting freely? If the situation is really as van Inwagen describes it, so that Alice has within one minute two and only two options, we should expect just the sort of outcome that van Inwagen describes: we should expect the ratio between her doing A and her doing B to converge in the long run. The difference between the case where it is a matter of chance whether A or B occurs and the case where Alice is choosing freely between A and B is not that in one case and not in the other there is convergence. The difference is that in the case where there is chance the action is the result of an indeterministic process, whereas in the case of Alice choosing freely there is a choice event initiating 14 the action process, an event that is not the result of a causal process (deterministic or indeterministic). The reason why we should expect the convergence on the assumption that Alice is free too is the following. Whatever Alice does she does either following a natural inclination or following a belief why it would be good to do the one thing rather than the other thing. If she has an inclination to do A and no counteracting inclinations and no beliefs that B would be better, then she will invariably freely do A. If [|191] she has a desire to do A and an equally strong desire to do B and no further beliefs about which is better, then it is unpredictable in each case what she will do, and it is predictable that if the situation is repeated often then the ratio will converge to 1/1. If she has, besides the natural inclinations, certain beliefs about A being better than B, then the proportion of A-actions will be greater. In any case, if she has in each case the same beliefs, the same inclinations, and the same character, then the ratio will converge.6 We should expect the convergence on the assumption that Alice is acting freely as well as on the assumption that she is not free. If we have reason to believe that Alice is acting freely, then we have thereby reason to believe that her acting is not a mere matter of chance. As we should expect the convergence in any case, whether Alice is acting freely or whether her acting is a matter of chance, conducting the sort of experiment which van Inwagen describes does not help to find out whether Alice is acting freely. An experiment only makes improbable a certain hypothesis if the outcome is different from what we should expect on the hypothesis. The hypothesis in this case is that 6 For similar arguments for this claim see (Swinburne 1997, 259-261). 15 Alice is acting freely. The outcome of van Inwagen's experiment is that the ratio of A to B converges, and that is what the hypothesis leads us to expect. The fact that the hypothesis that Alice's acting is a matter of chance leads us to expect the same outcome does not speak against the hypothesis that Alice is acting freely. Therefore van Inwagen should not conclude from his thought experiment that Alice's acting is a mere matter of chance and therefore not free. As the argument is flawed it does nothing to discredit the concept of agent causation. The concept of agent causation helps us to describe the difference between the case where Alice is acting freely and the case where she is not free. The cases differ in their causal structure. If Alice is acting freely, then the action result is the result of an action process that starts with an initial event, a part of which (the choice event) is not the result of a process and occurs because of Alice's choice. If, however, Alice's acting is a mere matter of chance, and hence if she is not acting freely, then the action result is just the result of a process – in this case an indeterministic one – which at no stage involves a choice event. Van Inwagen's thought experiment does nothing to show whether we have free will and what free will is and how it works. Different considerations would be required in order to find out whether we, or some other beings, have free will. This is not the place to pursue this.7 For our project here we only need to know what it would be like if someone had free will. I conclude that van Inwagen's argument also does nothing to discredit the concept of agent causation. [|192] 7 For arguments for free will see (Swinburne 1997, ch. 13). 16 4 Is agent causation mysterious? To many agent causation as I have described it will seem metaphysically extravagant or mysterious. Consider two kinds of objections. First, one may object that the occurrence of choice events is incompatible with what we know about the causal structure of the world. Second, one may object that the relation between an agent and his choice event is mysterious or unintelligible.8 The first type of objection is based on the idea that any event is either 'necessitated' by a set of earlier events or it is the result of an indeterministic process. In event causation that involves no chance, according to this idea, which we may call causal necessitarianism, there is at a time t1 a certain set of events, A, that makes it inevitable that at time t2 later than t1 event B occurs. Once A has occurred it is impossible that B does not occur.9 There is no reason to believe that there is causation of this type. How should events at one time necessitate in this way what occurs at a later time? There is always the possibility that something occurs after t1 and before t2 that prevents the occurrence of B. Consider what the causal 8 (Clarke 2000, 21), in this context, speaks of 'extravagant metaphysical commitments'. (Honderich 1993, ch. 3) makes both kinds of objections. Objections of the second kind (the unintelligibility objection) are raised by (Kane 1985, 72) and (Watson 1987, 167). 9 Mellor, for example, thinks that there are causes which are in this sense 'sufficient' for their effects. He writes: 'By causes that determine their effects I shall mean ones that are in the circumstances both sufficient and necessary for them.' (Mellor 1995, 133) Similarly (Hausman 1998, 33) and (Bigelow and Pargetter 1990, 290). 17 processes we know are like, e.g. a rolling billiard ball. Imagine even Newtonian physics to be true and hence the process to be deterministic. Even in that case the process is of course not so that nothing can stop it. If there is nothing that stops it, then it will carry on, but it is possible that something intervenes, e.g. another billiard ball or a cat jumping on the table. If there are entities that have the power to let certain events pop up (so that they have no preceding cause), then these events may well be interventions in causal processes. The question is whether there are such entities, but there is nothing in the nature of the causal processes we know (even the most 'deterministic' processes) that speaks against the existence of such entities. The other way of how an event may come about which causal necessitarianism allows is that an event is the result of an indeterministic process. But this brings us only to the second horn of the dilemma of free will. An event that is caused indeterministically is still caused by earlier events and the agent has no control over it. The second type of objection is that the relation between an agent and his choice event is mysterious or unintelligible. To this I reply that it is not more mysterious than the other ways how an event can come about. That an agent should make an event occur [|193] in the way described is at least as mysterious as that an event at one time should make it that a certain event at a certain later time occurs. 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