Disputatio, Vol. I, No. 17, November 2004 Book reviews Truth and Truthmakers, by D. M. Armstrong. Cambridge: Cambridge University Press, 2004, xii + 158 pp., £17.99. Given his important contributions to the philosophy of mind and metaphysics, David Armstrong could be content to merely rehearse these views – or even ride off in the philosophical sunset – his status as a major late twentieth century philosopher secure. Instead he remains active and intellectually engaged, continually rethinking and revising his earlier positions in light of the current literature. And, as a result, one way of viewing Truth and Truthmakers is as a snapshot of Armstrong's evolving philosophical picture. But in addition, it is an attempt to systematize this picture by embedding it within Truthmaking theory. Not only do we get an account of his current metaphysical views regarding properties, modality, mathematical entities, causation, and the like, we also get an argument that these views meet the desiderata of Truthmaking theory – yielding appropriate truthmakers for the corresponding truths. The framework within which Armstrong attempts to embed his specific metaphysical views – Truthmaking theory – is both familiar and confounding. It is familiar because the truthmaking relation just is the correspondence relation of the old correspondence theory of truth, and truthmakers are just those features of reality to which the truths correspond – traditionally, 'the facts' (Armstrong 2004, p. 16). It is confounding because Truthmaking theory presupposes both a realist metaphysic and the correspondence theory of truth: the 'powerful concept' (p. xi) of a truthmaker comes into play only after most of the heavy lifting has already been done. Armstrong does suggest that Truthmaking theory does provide an 'interesting' (p. 20) test of specific metaphysical theories and an 'illuminating and useful' (p. 23) regimentation of the broader metaphysical enterprise, but neither suggestion confers a particularly compelling motivation upon it. Book Reviews 75 The relata of the truthmaking relation, as Armstrong formulates things, are respectively true propositions and 'portions of reality.' A particular truth and reality-portion stand in this relation just in case it is in virtue of the latter that the former is true (p. 5). Governing Armstrong's search for truthmakers are two guiding principles: Truthmaker Maximalism – every truth has a truthmaker – and Truthmaker Necessitarianism – truthmakers necessitate their truths (p. 5). There are also a couple of additional principles that play a key role in Armstrong's argument at various points. The first – the Entailment Principle – specifically applies to the truthmaking relation. According to this principle, if a portion of reality T is a truthmaker for a proposition p, and p entails another propositions q, then T will also be a truthmaker for q (p. 10). The second principle – the Eleatic Principle – is motivated by epistemic considerations. It requires of candidate truthmakers that they 'make some sort of contribution to the causal/nomic order of the world' (p. 37) – otherwise, we could have no knowledge of them. For better or worse, Armstrong uses this principle to deny both non-actual possible worlds and uninstantiated universals any role in his metaphysical picture (p. 38). The fit between Armstrong's current metaphysical views and the truthmaking considerations he raises in support of them, however, is less than perfect. Armstrong concedes that, although they do favour realism about properties (p. 42; as far as I can tell, however, it is his Euthyphro argument and not truthmaking considerations that Armstrong deploys in support of this point), such considerations do not suffice to establish his own particular version of property realism – immanent categorical universals instantiated by particulars: when we come to the fine structure of the ontology of properties ... truthmaking theory does not seem of very great help in reaching a decision between the competing theories. (p. 43) Moreover, his Eleatic rejection of both uninstantiated universals and the Lewisian pluriverse yields a self-confessed ambivalence towards the prospects for finding truthmakers for certain truths, contra Truthmaker Maximalism: [in] the past I was at first so daunted by the problem of finding truthmakers for these statements that I suggested that alien properties and relations ... are not in fact metaphysical possibilities at all. (p. 88) Book Reviews 76 And by the time we reach his discussion of causation and dispositions, truthmaking considerations have mostly faded into the background. Not quite square pegs in round holes, but perhaps elliptical pegs. There are, moreover, deeper problems that arise for Armstrong's picture. The first hint of difficulty stems from his more or less offhand identification of truth-conditions with propositions (p. 17). This identification might seem natural as long as propositions are understood to be sets of possible circumstances or properties instantiable by the same. This would allow us to retain the idea that a belief or statement is true just in case its truth-conditions obtain, that is, just in case the set of circumstances in question includes an actual state of affairs, or the property in question is (actually) instantiated. But his adherence to the Eleatic principle prevents Armstrong from considering either account of propositions and, hence, the corresponding accounts of truth-conditions. After all, they invoke, respectively, non-actual states of affairs and uninstantiated properties (at least in the case of false statements). To avoid this worry, Armstrong takes propositions (and, hence, truth-conditions) to be properties of token beliefs and statements: the falsity of a belief or statement does not render its content properties uninstantiated (p. 13). As an account of propositions this may well be okay, but as an account of truth-conditions, it seems askew – truth-conditions intuitively fall on the 'world' side of the 'mind-world' divide. And where there's smoke... Armstrong's account of propositions almost immediately runs afoul of the very same sort of difficulty that arose for the alternative accounts he rejects. The problem is that of unexpressed propositions – propositions that no one ever has or ever will state or believe. The natural suggestion would be to treat them as uninstantiated properties of beliefs and statements, but, as above, Armstrong rejects uninstantiated properties. Instead, he suggests that unexpressed propositions should be identified with '... the mere possibility of the instantiation of such a property' (pp. 15-6). In order to adjudicate this maneuver, we will have to investigate Armstrong's general account of the truthmakers for the truths of mere possibility. The truths of mere possibility are the contingent falsities – propositions of the form <~p & ◊p>. In light of the fact that <~p>, if contingent, entails <◊p>, Armstrong deploys the Entailment principle and concludes that the truthmaker for <◊p> (as well as for <~p & ◊p>) just is the truthmaker for <~p> ( p. 84). Such propositions, however, are negative truths, and so, ultimately, the truthmakers for Book Reviews 77 the truths of mere possibility are the truthmakers for the negative truths. Now, according to Armstrong, the truthmaker for a negative truth of a certain kind consists of the mereological sum of the truthmakers for all the truths of that kind plus the (higher order) fact that these are all of the truthmakers of the relevant kind (p. 58; in fact, this mereological sum of truthmakers is a constituent of the fact (or state of affairs) that these are all the truthmakers). So, for example, the truthmaker for <Alward is not a physician> is the mereological sum of states of affair in which I am involved plus the fact that this collection of states of affairs includes all of the states of affairs in which I am involved. What remains to be done is to apply this account of mere possibility to Armstrong's identification of unexpressed propositions with the mere possibility of the instantiation of content properties. Consider an unexpressed proposition <p>. Let us suppose that F-ness is the (content) property that a belief or statement has in virtue of being a belief or statement that p. Armstrong's suggestion seems to be that the unexpressed proposition <p> just is (in the sense of identity) the truthmaker for <(F-ness is not instantiated) and ◊(F-ness is instantiated)>. And this is just the truthmaker for <(F-ness is not instantiated)> – the mereological sum of all the content properties instantiated by any statement or belief plus the fact that these are all the instantiated content properties. There are, however, a number of reasons to balk here. The first worry is methodological. Armstrong makes explicit appeal to entailment relations between propositions in the reasoning that underpins his account of truthmakers for mere possibilities and, hence, his account of the nature of unexpressed propositions. But insofar as entailment relations between propositions are a function of their nature, any appeal to entailment relations between unexpressed propositions in reasoning aimed at discerning this nature is inapposite. And if a proposition <p> is unexpressed, so to, presumably, is <(Fness is not instantiated)> and <◊(F-ness is instantiated)>, where Fness is the property of being a belief or statement that p. Although this does not render Armstrong's account of the nature of unexpressed propositions circular or otherwise defective, it does bring into question some of the reasoning leading to it. The more serious difficulties stem from the fact that Armstrong's theory individuates unexpressed propositions far too coarsely. At first glance, the theory seems to imply that every unexpressed proposition is identical to the same complex entity – the mereological sum of all Book Reviews 78 the content properties instantiated by any statement or belief plus the fact that these are all the instantiated content properties – and, hence, to one another. Now if propositions <p> and <q> are identical then, not only do they entail one another, but of necessity they share the same truth-value. And since, if <p> is unexpressed, so is <~p>, Armstrong's view seems to imply that not only do unexpressed propositions entail their negations, they also share truth-values with them. This clearly will not do. Now Armstrong might rejoin by invoking the notion of a minimal truthmaker: '[if] T is a minimal truthmaker for p, then you cannot subtract anything from T and the remainder still be [sic.] a truthmaker for p' (pp. 19-20). And he might deploy this notion as follows: although all of the propositions of the form <(F-ness is not instantiated) and ◊(F-ness is instantiated)> at issue share the aforementioned truthmaker, they differ in minimal truthmakers. And it is the more finely grained minimal truthmakers that are identical to the corresponding unexpressed propositions. It is far from clear, however, exactly how promising this suggestion is. It requires finding a way of 'carving up' the mereological sum of all instantiated content properties so that each distinct unexpressed proposition can be identified a distinct 'part' of this mereological whole. Moreover, the assignment of parts to unexpressed propositions needs to be done in a way which respects entailment relations among the latter. This is, at best, rather a tall order. Despite these difficulties, Armstrong's little book is well worth reading. It is clear and engaging, and filled with ideas and arguments. Armstrong's attempt to embed his specific metaphysical views within the broader framework of Truthmaking theory does run into rough seas. But the trouble here is not Truthmaking theory per se; it is instead the more general Eleatic principle on which he relies. Worries about knowability are what drive Armstrong towards the account of propositions he defends, and upon which he runs aground. (Armstrong does not consider a Russellian account of propositions. Arguably one could have knowledge of such entities by means of one's knowledge of their constituents.) Peter Alward Dept. of Philosophy University of Lethbridge 4401 University Drive Lethbridge, Alberta T1K 3M4, Canada peter.alward@uleth.ca