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Action and its Explanation$

David-Hillel Ruben

Print publication date: 2003

Print ISBN-13: 9780198235880

Published to Oxford Scholarship Online: October 2011

DOI: 10.1093/acprof:oso/9780198235880.001.0001

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(p.218) Appendix on the Epistemology of Action: Certainty and Basic Physical Action

(p.218) Appendix on the Epistemology of Action: Certainty and Basic Physical Action

Action and its Explanation

Ruben David-Hillel

Oxford University Press

Philosophers of knowledge not so very long ago were much exercised with the topic of infallible, indubitable, or certain contingent knowledge. Could claims about the contents of one’s present experience be certain, as many empiricists supposed? Could claims about one’s own existence be indubitable, as Descartes argued? Some philosophers were prepared to extend the list of what can be known with certainty to include beliefs about one’s own basic actions, or anyway about some of them, for it seemed that the knowledge a person can have about his basic actions has a peculiar and rather special kind of authority.

An example of this is Stuart Hampshire and H. L. A. Hart’s ‘Decision, Intention, and Certainty’.1 The main thrust of the article was to argue that a person’s beliefs about his own actions, wants, and the like are not based on any sort of observational evidence, and this is, of course, not the same thing as these beliefs being known with certainty.2 Moreover, beliefs about actions were of interest to Hampshire and Hart mainly in so far as they were beliefs about one’s future actions, based on the intentions persons have regarding their future performances.

However, Hampshire and Hart did claim in addition that ‘…in this article we are concerned with only one case of the kind of certainty…that cannot be associated with any appeal to evidence: namely…a man’s (p.219) knowledge of his own present and future voluntary actions’ (emphasis added).3 They had in mind what I have been calling ‘physical actions’, and it is the certainty or otherwise of that class of actions that shall occupy me in this appendix. If one focuses on mental actions, the topic may not remain distinct from the question of the certainty of the mental in general. I have said something in Chapter 2 about Descartes’s claim of certainty for his knowledge that he is thinking, a mental activity. In any event, I have nothing further to say about the certainty of one’s mental actions, say acts of will or tryings, if there are such and if some of them are also basic if or when they occur.

Although Hampshire and Hart admit that ‘there is a sense in which our own declarations about our current actions may be mistaken’ (p. 9), this qualification has to do with the unintended consequences of what a person does intentionally, so that a person might misidentify or fail to identify his unintended, non-basic actions. Concerning such basic physical actions as there are (although they do not put the point in this way), perhaps the moving of parts of one’s own body, their view seems to have been that a person can know for certain at t what they are doing at t.

Can we have Certain Knowledge of our Basic Physical Actions?

I use but do not explicate the idea of certainty or certain knowledge, beyond the limited assumption needed for this appendix: the idea of certainty involves the thought that belief entails the truth of what is believed.4

There is a weaker and a stronger claim of Cartesian certainty concerning one’s token basic physical actions. The weak claim, (1), is that an agent can have certain knowledge that he is acting when he basically physically acts; that is, that he can know for certain that he is doing something or other, whether or not he can know for sure what it is that he is doing. A stronger claim, (2), is that, for at least some token basic physical action, a, if the agent is a-ing, then he can have certain knowledge that he is a-ing. The agent couldn’t be wrong as to whether or not he is a-ing. Stronger still is the last claim, but altered to apply either (3) to all rather than some of an agent’s basic physical actions, or (4) at least to all of the agent’s basic physical actions of the same action type as a.

A distinction is sometimes drawn in the literature, between certainty and self-warrant. Roughly, certainty that p is defined as: ‘X believes that p (p.220) entails ‘p’; its being self-warranting that p is defined as: ‘p’ entails ‘X believes that p’. I don’t think that even basic physical action is, in any sense, self-warranting. An agent can basically physically act without believing that he is acting, either in that way or in any way at all. In the sense discussed in Chapter 4, I would claim that when a person basically physically acts, he may be disposed to believe that he is acting and indeed disposed to believe that he is acting in that specific way. But dispositions to believe are not beliefs, not even dispositional beliefs.

The certainty claims about basic physical action are these:

  1. (5) There is no possible world in which a person believes that he is doing something, and it is false that there is something that he is doing.

  2. (6) For at least some token basic physical action description, ‘a-ing’, there is no possible world in which a person believes that he is a-ing and he is not a-ing.

The quotation from Hampshire and Hart seems to commit them to (6). In any event, I am interested in the truth or otherwise of (5) and (6), not in the accuracy of the attribution.

The distinction between (5) and (6) is controversial, since some philosophers have said that for a person to believe that he is acting is always for him to have in mind some specific act type, say, ‘A’, such that he believes that he is a-ing and that his a-ing is a token of the type A. Even if that view were correct, one might still maintain that one of the two beliefs was certain and the other not, but the distinction would become much more problematic.

Some Counter-Examples

Here are two examples that question the possibility of certainty even about one’s own basic physical action. William James cites both.5 (a) Professor Strümpell describes his ‘wonderful anaesthetic boy’: ‘Passively holding still his fingers did not affect him. He thought constantly that he opened and shut his hand, whereas it was really fixed.’ (b) Dr Landry describes a blindfolded patient thus: ‘If, having the intention of executing a certain movement, I prevent him, he does not perceive it, and supposes the limb to have taken the position he intended to give it’.

If opening and closing one’s hand or ‘executing a certain movement with a limb’, at least on the occasions being considered, are basic physical actions, both Strümpell’s and Landry’s cases show that both (5) and (6) cannot be sustained. In both cases, the person has done nothing, or anyway (p.221) executed no physical action, but falsely believes that he has done something, and indeed falsely believes that he has a-ed, where ‘a-ing’ is a basic physical action description. That is, the agent believes that ‘a-ing’ refers to his token basic physical action when it in fact refers to nothing.

The wonderful anaesthetic boy falsely believed that he opened his hand; Landry’s patient falsely believed that he had executed a certain movement with a limb. In both cases, no physical action occurred, basic or otherwise. Of course, one cannot ‘disprove’ (6), which is an existential generalization, by way of disconfirming examples. But I think that the two examples cited by William James do undermine any plausibility that (6) might initially be thought to have.

Another counter-example to the two certainty claims might be this. Phantom limb cases concern sensations in non-existent limbs, but I can see no reason for thinking that there could not be cases of phantom limb actions (indeed, perhaps there are). If, unbeknownst to a person, his hand were amputated, he, if blindfolded, might still falsely believe that he moved the fingers of that hand in various ways.

The examples would make the same point if, for example, the wonderful anaesthetic boy’s hand had been opened and shut after all, but not by him, but rather by some force made invisible to him. The boy might then have falsely believed concerning some mere physical occurrence involving his body, the opening and closing of his hand, that it was a basic action of his, when in fact it was not. James’s counter-examples do not have to concern beliefs about action rendered false by total lack of movement; the counterexamples could also concern beliefs about action rendered false by the occurrence of mere bodily movements that are not actions. So not only can a person falsely believe that he is basically physically acting when nothing relevant whatever occurs. Concerning some mere event or happening, perhaps the opening of his hand, a person could falsely believe that that mere event is his basic physical action (his opening of his hand) when it is not an action at all.

Perhaps we are looking at the wrong sort of beliefs about basic physical action in order to find certainty. The belief a person has that he is basically physically acting, and the belief that he has that he is a-ing, are positive action beliefs. The examples James cites show that, if movings of one’s body are basic physical actions, then a person’s positive basic action beliefs cannot be certain. On the other hand, the belief of a person that he is not engaging in any physical action whatever, and the belief that he is not a-ing, not doing any action of type A, are negative action beliefs. Perhaps a person can (p.222) be certain about his negative basic physical action beliefs. Such claims would go like this:

  1. (7) There is no possible world in which a person believes that he is doing nothing at all, and there is something that he is doing.

  2. (8) For at least some token basic physical action description, ‘a-ing’, there is no possible world in which a person believes that he is not a-ing and he is a-ing (namely, there is no possible world in which a person believes that he is not doing any basic action of type A but in fact he is doing a basic action of type A).

Notice that any philosophical doubts, mentioned above, concerning the distinction between the two positive action beliefs, (a) the belief that one is doing something or other and (b) the belief that one is a-ing, will not apply in the case of negative action beliefs. A person can surely (c) believe that he is not acting at all, without (d) there being any specific token basic physical action description ‘a-ing’ whatever such that he believes that he is not a-ing.

What connection if any, is there between positive and negative action beliefs? Belief is not closed under logical implication, and arguably not even under known logical implication. Of course, the person who believes that he is bending his left index finger, and who believes that bending and straightening the same index finger at the same time is conceptually impossible, may indeed also believe that he is not straightening his left index finger. But even if he does not actually believe that he is not straightening his left index finger, surely he at least must be disposed to believe that he is not straightening that index finger.

On the other hand, one can’t infer any positive action belief, or even just a disposition to hold any positive action belief, from a negative action belief, even if the assumption of belief in the conceptual impossibility is added. Suppose a person simply believes that he is not straightening his index finger. There is no positive action belief, or disposition thereto, that he thereby must have, on the basis of that fact alone (plus his belief in the conceptual impossibility of both bending and straightening the same finger at the same time).

Notice that (7) and (8) concern beliefs about what is not the case, which is of course not the same thing as having no beliefs at all. The impossibility in question, claimed by (7) and (8), does not consist in a person’s acting when he fails to believe anything whatever regarding his actions, but only (p.223) when he has a negative action belief, when he actually believes that he is not doing something or anything.6

Suppose that ‘the opening of my hand’ and ‘the closing of my hand’ are, on the occasions under investigation at any rate, token basic physical action descriptions, uttered by Professor Strümpell’s wonderful anaesthetic boy. That is, if they refer to anything at all, they refer to one of his basic physical actions. The boy is not asked whether he has opened and shut his hand, to which he gave the wrong answer, but rather he is asked whether he has not opened and shut his hand.

As we have seen, Professor Strümpell’s wonderful anaesthetic boy can believe that he has opened and closed his hand when he has not, but how could he believe that he has not opened and closed his hand when he has? Perhaps, if he were to believe that he has not opened and shut his hand, he could not fail to be correct. In general, if a person believes that he has not a-ed, where ‘a’ is a token basic physical action description in the sense I explained, then isn’t it true that he has not a-ed (as (8) asserts)?

Are (7) and (8) true? Let me defend the thesis from an unsuccessful line of attack, before I consider an objection which will force us to reconsider and reword the thesis. The following case, quoted by Hugh McCann, when duly altered, might make one wrongly doubt (8) (not that McCann himself uses it for any such purpose):

‘Watch what I’m doing: I’m touching each of my fingertips against my thumb…Let me see how well you can do that with your left hand.’

I could scarcely do it at all. When I ordered the index finger down, the middle finger, perhaps, wavered towards my thumb. Successive attempts made it apparent that my left-hand fingers and my wishes for them were at odds.7

Let me slightly amend the example, to produce examples of negative, rather than positive, action belief. It seems plain that McCann’s case could (p.224) be amended so that the person was blindfolded and anaesthetized in such a way that he could not observe or feel what had happened. He might then falsely believe that he had bent his index finger, when in fact his middle finger had wavered (‘the middle finger…wavered’).

Suppose the person believes, consciously and explicitly, that bending one finger while waving another on the same hand at the same time is physically impossible for him. Believing the impossibility, he might then have or acquire the desire and intention not to wave his middle finger, since he wants to bend his index finger.

If bending an index finger and waving a middle finger are or could be basic actions for him on this occasion, then, so it might be held, the person in McCann’s case might believe that he had not waved his middle finger (because he believed that all that he had done was to bend his index finger and believed that that is incompatible with him waving his middle finger), when in fact he had waved his middle finger. So (8), it will be claimed, is false. Again, he believes that he has not waved his middle finger, because he believes that he has bent his index finger, and believes the incompatibility of index finger bending and middle finger waving, but because of the wish–finger mismatch, he does wave his middle finger after all. Doesn’t this show that (8) is false? He holds, does he not, a negative basic physical action belief (‘I have not waved my middle finger’) that is false?

In fact, the amended case does not constitute a counter-example to (8), and the language with which McCann describes the case explains why. We can bring this out by asking this question: did the person really wave his middle finger or not? True, the person believes that he is not waving his middle finger. The case is a counter-example, though, only if it is true that he did wave his middle finger when he believed that he was not waving it. There is a strong argument for it being the case that he does not wave his middle finger at all.

What then happens, if he does not wave his middle finger? I think that what happens in this example is that a mere event occurs, a wavering of his middle finger, which is intrinsic to no action of his at all, but is only a bodily occurrence involving his finger. As McCann says, ‘the middle finger…wavered’, not that he waved it. If, when I am thinking about something unpleasant, I shudder or twitch, the shuddering or twitching is a mere event, nothing I do in the actional sense (even though it is true that I shudder or that I twitch, these doings are not actions of mine). They are not even unintended actions of mine; they are no actions of mine at all. They are involuntary reactions of my body. So it seems one might think of the finger (p.225) wavering in this way. It is simply an involuntary bodily response to whatever is going on inside the person. As the shuddering or twitching is to the unpleasant thought, so is the middle finger wavering to the wish to bend the index finger.

A steadfast opponent, wishing to treat this case as a counter-example to (8), might argue that this is a case of the agent’s middle finger waving action, in spite of what I have just said. True, the person intends and wishes not to wave his middle finger, but why can’t his action then simply be an unintentional waving of his middle finger? When we thought in terms of the accordion effect, in Chapter 2, the picture that emerged was that a basic physical action, itself intended or at least not unintended in the sense I explained, might have unintended, often increasingly remote, events as effects. Subject to certain not very clearly defined limitations, such events were intrinsic to the agent’s non-basic actions, and were such that he could be said to do these other actions by doing the basic one. Some of these actions could count as the agent’s unintended actions. If we apply the accordion effect to this case, why can’t the middle finger wavering be an event intrinsic to such an unintended action, so that he does wave his middle finger after all? How can I just assume that the middle finger wavering is a mere event, like shuddering or twitching, rather than an event intrinsic to an unintended action, which in this case would be the unintended action of his waving of his middle finger?

The distinction between basic and non-basic action is exhaustive. So, if there were, in this case, such an unintended action as his waving of his middle finger, it would have to be either a basic or a non-basic action. Recall that we have attributed to the agent the desire and intention not to wave his middle finger, since what he wanted to do is to bend the index finger and thought that the two actions, bending and waving, would be incompatible for him. His waving of his middle finger, if there were such an action, would have to be unintended by him in the case as I have described it, and unintended in the strong sense that it is something he intended not to do (and not just in the weaker sense that he might do it without intending to have done it).

Could his middle finger waving be a non-basic action? Non-basic actions can certainly be unintentional in that strong sense; a person might do something unintentionally that he actually intended not to do. But the topic under discussion is certainty about one’s basic physical actions. If the waving were a non-basic action, we would not be addressing the topic we have set ourselves, in so far as we focus on the waving.

(p.226) (But, in any event, the middle finger waving, had there been such an action, could not be an example of a non-basic physical action, since, in the example as McCann described it, there is no other physical action that the person did such that he might have waved his middle finger by doing it. Might the basic action in this case be a mental action, such as his trying or attempting to bend his index finger? Perhaps he unintentionally waved his middle finger by trying to bend his index finger? I won’t, in this appendix, rehearse my arguments about the ubiquity of tryings or willings as mental acts. But more to the point, the purpose of this appendix is to explore the question of the certainty of basic physical action. (8) makes a claim about basic physical actions, not about basic non-physical ones. Invoking tryings as basic actions at this point, which are mental actions if they are anything at all, would defeat that purpose.)

For the purposes of the discussion in this appendix, the possibility of the middle finger waving being a basic physical action is more plausible. Could the finger waving be a basic physical action? If the argument of Chapter 2 is correct, no basic physical action can be unintentional in this strong sense. A person can’t basically physically act in a way in which he desires and intends not to act. If he desires and intends not to do something, say wave his middle finger, and yet his middle finger waves, the case is compelling for the waving, or wavering, to be a mere event. So there is no such action at all, basic or non-basic, in the case described, as his waving of his middle finger. There is only the mere event, the wavering of his finger. The finger just wavers, without that wavering being in any sense under the agent’s control.

What happens when the person begins to understand the systematic mismatch between his wishes or intentions and fingers, as may happen with permanent cross wiring? Indeed, suppose he is fitted with Ginet’s mismatch machine.8 Ginet’s cases are expressed as a mismatch between action and volition. When he has a volition to bend his index finger, the person knows that he will wave his middle finger. What he really wants or intends to do is to wave his middle finger. So he volitions to bend his index finger, knowing that he will wave his middle finger as a result. I am not sure that I really understand this supposition. I shan’t pursue some of the difficulties I have in understanding the mismatch: in what sense can the person really have a bona-fide volition to do a, when what he wants to do, intends to do, wishes to do, is rather to do something else, b? Is he just pretending to have a (p.227) certain volition, in order to get the result he needs from the systematic mismatch machine? But a sham volition is no volition at all.

But let’s accept the Ginet mismatch as a possibility. I agree in that case that the story now has been altered so that the person is now genuinely acting, he waves his middle finger, and that this waving would be a basic physical action (again, discounting volitions as basic actions). A crucial difference in the amended case is that the waving of the middle finger is now intended, deliberate, done on purpose, and so can count as a basic physical action of the agent. Certainly, the waving of his middle finger is no longer something that he intends not to do.

But (8) is still untouched, for, knowing of the systematic mismatch, he will now believe that he has not bent his index finger (not: that he has not waved his middle finger). Given his understanding of the systematic mismatch, what he has done, and what he will believe that he has done, is to wave his middle finger. What he has not done, and what he will believe that he has not done, is to bend his index finger. Not doing something and belief about not doing it stay together. In Ginet’s systematic case, the systematic mismatch is allegedly between volitions and actions; the match remains between beliefs, negative and positive, and actions. Thus far, the certainty of negative basic physical action belief, (8), is untouched.

In The Man who Mistook his Wife for a Hat,9 Oliver Sacks describes a number of cases of patients with neurophysiological injuries resulting in loss of proprioception, ‘that continuous but unconscious sensory flow from the movable parts of our body (muscles, tendons, joints) by which their position and tone and motion is continually monitored and adjusted, but in a way which is hidden from us because it is automatic and unconscious’ (p. 42). Patients who have lost this ‘sense’ are unable to see their own body as ‘their own’. In one case, a man in a hospital bed finds a leg in bed with him. Assuming that it has been put there as a practical joke, he flings it in disgust from the bed, only to find that somehow he follows the leg out of bed, and ends up sitting on the floor, with this alien leg now inexplicably attached to him. In another case, Christina suddenly begins to feel ‘disembodied’, having lost throughout her entire body, from head to toes, the proprioception lost only in the leg by the man in hospital. Christina felt that no part of her body was hers.

As with many of the ‘pathological cases’ of action, it is not clear how we (p.228) are best to describe them, since we are using the vocabulary and structure derived from non-pathological cases. There is no suggestion that Christina or the man in hospital cannot act, and if they act at all, they must basically act in some way or other. So Christina might in fact move her body, say bend a finger. What does she believe? Sacks’s brief account does not tell us. It only tells us that she regards her body as ‘alien’.

It is crucial that it is their bodies that they consider to be alien, and not their actions themselves. That is: they do not consider the actions as not theirs. What might ‘considering one’s actions as alien’ mean, and why would it matter? One thing it might mean is this: then when Christina, for example, in fact acts in some way, she would not believe that it is she who is acting in that way. But that would only be to say that action is not self-warranting, not that it is not certain.

But if she considers her actions as alien, as not her own, might that not mean something else? When she believe that she is not acting in some way, might she be acting in that way all the same? That would count decisively against (8), but nothing in the story suggests, let alone requires, that description. She appears to know when she acts and when she does not, it is just that the acting ‘feels’ strange. The man in hospital believes that he has thrown a leg out of bed and indeed that is precisely what he has done. He simply does not know that it is his leg.

If the body is what is thought of as alien, as the two stories suggest, then what he or she must believe is that that they are acting but that the control they have is exercised over objects that are not any part of their bodies. Christina might feel as we would feel, in the speculation in Chapter 2, if we could directly control physical objects that were no part of our body. If Uri Geller bends a spoon as one of his basic actions, it does not follow that the spoon is connected to him by the sense of proprioception. This reading of the story also presents no challenge to (8). For Sacks’s stories to challenge (8), it is the actions themselves which would have to be considered alien, understood as I have indicated, and not just the objects on which the actions are directed. But nothing in the story as presented requires or even encourages us to take the story in this way.

All the same, in my view, even (7) and (8) cannot be true. Consider finally this case. We convince Professor Strümpell’s wonderful anaesthetic boy that the nerves responsible for opening his hand have been irreparably severed. In fact, this is not true; they are entirely intact. We also tell him that the friendly neighbourhood neurophysiologist will cause the movement (p.229) that is an opening of his hand, but of course a movement for which he will be in no way responsible (no such neurophysiologist is in fact on the scene).

For whatever reason you would like to imagine, we ask him to try and open his hand none the less, perhaps telling him that the attempt is for him to see just how ineffectual he is. He accepts, and sees his hand opening, but falsely believes that he has not opened his hand, and that the hand’s opening is only a result of the neurophysiologist’s activity. Hasn’t he in fact opened his hand, falsely believing that he has not opened his hand? Isn’t (8) false? Doesn’t he believe, even while he is opening his hand, that he is not opening his hand, because he believes that the neurophysiologist is opening his hand instead of him?

One possible line of response is to argue that, if he believes that it is not possible for him to open his hand, then he cannot try or intend to open his hand either, on the grounds that a person cannot try or intend to do what he believes it impossible for him to do.10 This response is controversial, but suppose it were so. And if so, he won’t open his hand after all. But then, his belief will not be false.

We can slightly amend the case to bypass this objection. In order for the amended wonderful anaesthetic boy case to work, what must be true is that the boy believes that he has not opened his hand when he has done so. He need not believe that it is impossible for him to open his hand. He might believe that his nerves are such that they work rather erratically–on any particular occasion, there is only a 1 per cent chance that they will work properly. So he tries to open his hand. Lo and behold, this occasion was the 1 in a 100. He does open his hand.

He does, of course, now see that his hand is open. But, given such a low probability, it is reasonable for him to believe, on the basis of the evidence that he has, that he has not opened his hand and that on this occasion the hand opening is a consequence of the neurophysiologist’s intervention. (Pick any percentage you wish, such that it allows him enough scope to try and open his hand yet is small enough to justify his believing that he did not succeed in opening it on this occasion.) So he will be wrong: he is opening his hand, in spite of his belief that he is not. There is a convincing counterexample to (8).


(1) Stuart Hampshire and H. L. A. Hart, ‘Decision, Intention and Certainty’, Mind, 67, 1958: 1–12.

(2) The contemporary locus classicus for discussion of knowledge of one’s own actions not resting on observational evidence is Professor Anscombe’s Intention, Oxford: Blackwell, 1963: 49 ff.

(3) ibid. I.

(4) For a good discussion and pertinent distinctions, see Roderick Firth, ‘The Anatomy of Certainty’, Philosophical Review, 1967: 3–27.

(5) William James, The Principles of Psychology, ii, London: Macmillan, n.d.: 489–92.

(6) There is a long tradition of taking certain sorts of non-changes as a kind of change, so that in an extended sense refraining from acting counts as a kind of acting. See Myles Brand, ‘The Language of Not Doing’, The American Philosophical Quarterly, 8, 1971: 45–53. A person lying in bed, with no thought about rising, may well be doing nothing with respect to his rising. A person lying in bed, who knows that his non-arising will annoy someone whom he wishes to annoy, may well be refraining from arising. (Most parents of teenagers know of this case all too well) A person who does nothing at all with respect to rising must both (a) not rise and (b) not be refraining from rising.

(7) E. Hodgins, Episode: Report on the Accident inside my Skull, New York: Atheneum Press, 1964: 27, quoted by Hugh McCann, in ‘Trying, Paralysis, and Volition’, Review of Metaphysics, 28, 1974: 423–42.

(8) Carl Ginet, On Action, Cambridge: Cambridge University Press, 1990: 42–4.

(9) Oliver Sacks, The Man who Mistook his Wife for a Hat, London: Pan Books, 1986. Page references in the text are to this volume.

(10) See the extensive literature on this question, e.g. Michael Bratman, Intention, Plans, and Practical Reason, Cambridge, Mass.: Harvard University Press, 1987: 37–41; Myles Brand, Intending and Acting, Cambridge, Mass.: MIT Press, 1984: 148–52; Alfred Mele, Springs of Action, New York: Oxford University Press, 1992, ch. 8.