10 I Do Not Exist PETER UNGER It seems utterly obvious that the question 'Do I exist?' may be correctly answered only in the affirmative; of course the answer must be 'Yes.' Descartes, it may be said, made this idea the keystone of his philosophy, he found it so compelling. Hume, however, in his characteristically sceptical style, at least at times questioned the propriety of an affirmative reply. My teacher, Professor Sir Alfred Jules Ayer, to whom this essay is dedicated, customarily expressed himself in a conditional manner, which I find quite con­ genial: The sentence 'I exist', in this usage, may be allowed to express a statement which like other statements is capable of being either true or false. It differs, however, from most other statements in that if it is false it can not actually be made. Consequently, no one who uses these words intelligently and correctly can use them to make a statement which he knows to be false. If he succeeds in making the statement, it must be true. 1 Of course Ayer is right in pointing to the absurdity of a person's trying to deny his own existence. Prepared to pay this price, in this brief essay I mean to deny my own putative existence, a position which I take to be even more radical than Hume's. This is owing not to a desire to be more perverse than any of my predecessors, but, rather, to certain arguments which have occurred to me, and which seem quite far from any of their thoughts. As may be expected of a student of Ayer's, and as I have indicated, I appreciate the utterly paradoxical position into which these arguments lead me. But I venture to suppose that this does not reflect badly on my reasonings in any relevant regard. Rather, it may show their great scope, thus highlighting obscure defects in prevalent conceptions. With this understanding, I mean to present herein the main lines of reasoning against my own existence. I offer my arguments as a challenge to any others that there G. F. Macdonald (ed.), Perception and Identity © Graham Macdonald, Michael Dummett, P. F. Strawson, David Pears, D. M. Armstrong, Charles Taylor, J. L. Mackie, David Wiggins, John Foster, Richard Wollheim, Peter Unger, Bernard Williams, Stephan Körner and A. J. Ayer 1979 236 Perception and Identity may be, so that they may dissuade me from the path of extreme nihilism that reason appears to require. Accordingly, I shall present my ideas as forcefully as possible, not to indicate any enormous confidence on my part, but rather to provoke others to reply most promptly and effectively. For my own part, I can find nothing importantly wrong with the uncomfortable thoughts I shall thus boldly put forth. The more I reflect upon them, the more I become convinced of their essential truth or justice, for any errors I ever find are superficial mistakes, requiring at most only minor changes in formulation. As a consequence, there appears to be growing within me an inclination to expend much effort toward developing the required nihilism in great detail, no matter how painfully labor­ ious the attempt may be. Perhaps this growth had best be stopped, but then only by an appropriate rational argument. To compound my dilemma, I notice that, in general outline, the same view lately has been conjectured by another writer, Samuel Wheeler, or so it appears. In a pioneering paper, 'Reference and Vagueness', Wheeler conjectured that there may not be any people; I should suppose he meant to include himself. 2 While he does not offer a positive argument for the nihilistic surmise, he does disarm prevalent ideas which would point the other way. Appearing to find a similar current in another, but no adequate compelling force in the opposite direction, the situation encourages my thoughts to move, however slowly and painfully, toward their properly destructive denial. Perhaps a response to my challenge may save me from the ultimately fruitless labours I seem required to under­ take. The challenging position is this: I do not exist and neither do you. The scientific perspective, especially as developed over the last few centuries, compels this result. Now, there is nothing espe­ cially unfortunate in this as regards the human condition. For, as regards almost everything which is commonly alleged to exist, it may be argued, in like manner, that it in fact does not. There are, then, no tables or chairs, nor rocks or stones or ordinary stars. Neither are there any plants or animals. No finite persons or conscious beings exist, including myself Peter Unger: I do not exist. So much for this challenging position. To the main arguments for it, rather briefly presented, I now turn. I. THE SORITES OF DECOMPOSITION Tables, as well as chairs, have often been believed to be paradigms of existing things or entities, but I shall argue that they do not exist at all. They are, if you will, only fictions, though nothing Peter Unger 237 whatever depends on my use of such a term of convenience. My argument will be in the form of an indirect proof, wherein I reduce to absurdity the supposition of their existence. According to our modern scientific view, if there are any tables, then each of them is constituted of, or is composed of, or comprises, or consists of, or whatever, many atoms, and still more 'elementary particles', but only a finite number of each. Now, nothing here depends on the expression 'is constituted of, or on any similar expression. Baldly put, the point is this: where and when there are no atoms present, there and then there is no table. This idea is not crucial to the argument; a 'less scientific' analogue will work as well, so far as the purer logical features go. But it is good to have nature appparently so co-operative. Now, at the same time, according to our common-sense view of the matter, which for something like a table is, of course, all but definitive, one atom, or only a few, removed, or added, quite innocuously, will not make a relevant difference. If you have a table at the start, then, after an atom has been gently ticked off the edge somewhere, there will still be a table present. These simple ideas, when brought into combination, leave nothing for reason but to conclude that there really are no tables. It takes no great acumen to see this, as the reasoning is utterly simple, and most just and suitable to the subject before us. For, if there is a table there, then it has only a finite number of atoms - say, a billion billion; it does not matter. The net removal of one, then, leaves us with a supposed table of a billion billion minus one atoms; after two are removed, the supposed table has a billion billion minus two; and so on. After a billion billion atoms have been removed, we have a table consisting of no atoms at all. In this simple fashion, I suggest, we have reduced to an absurdity the supposition that the table in question exists, or ever did exist. As this argument may be most readily generalised, we may conclude that there really are no such things as tables. To advance discussion, it may be helpful if I give the argument just presented something like a formal shape or presentation. We begin with a supposition of existence: (1) There exists at least one table. But, from our scientific perspective, we may add this second premiss: (2) For anything there may be, if it is a table, then it consists of many atoms, but only a finite number. 238 Perception and Identity From these two premisses, we may deduce that there is at least one table which consists of many atoms, but a finite number of them. The crux and bite of my argument, however, may be supposed to come with a third and final premiss: (3) For anything there may be, if it is a table (which consists of many atoms, but a finite number), then the net removal of one atom, or only a few, in a way which is most innocuous and favourable, will not mean the difference as to whether there is a table in the situation. These three premisses, I take it, are inconsistent. The assessment of this inconsistency, I submit, leads one to reject, and to deny, the first premiss, whatever one may subsequently think of the remain­ ing two propositions. Discounting minor matters of formulation, I doubt that many would deny our second premiss. Many more, I imagine, are liable to deny our third and final proposition. It has, I must admit, been stated in a way which leaves matters less than completely clear and evident. Accordingly, I shall try to provide some clarifica­ tory interpretation, to the extent that this seems merited even in a very brief treatment. I have said that an atom is to be removed in a way which is most innocuous and favourable. What do I mean by such a way? First, I mean for the removal to be net, of course, and in the fullest way. The process which removes an atom does not put something else in its place, or in anywhere else; nor does such a thing happen in any other way. And, what is removed is randomly cast aside, so to speak. Secondly, I mean for the net removal to take place with as little disruptive effect as possible on what remains, especially as regards the question, if it really has any substance, as to whether or not any table remains.