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Showing posts with label Dialetheism. Show all posts
Showing posts with label Dialetheism. Show all posts

Monday, April 7, 2014

Analytic Philosophy: Ontological Contradictions

Not my usual style, but, like the last paper, I wrote this for a logic/metaphysics seminar...

Ontological Contradictions & Dialetheist Correspondence
I. Introduction
Quite apart from the viability of a given system of paraconsistent logic, there is the question as to the metaphysical import of true contradictions. Whatever this import turns out to be, there is no doubt that it is intimately related to the theory of truth one adopts. While deflationism's relation to ontological contradictions is anything but clear, it is apparent that a correspondence theory of truth must have a viable theory thereof. In the interest of ontological contradictions, I aim to show in this paper that the connection between them and correspondence is not so hard to swallow as one might suppose. To this end, I am up against the viewpoint of Armour-Garb and Beall, which restricts true contradictions to ungrounded, semantically pathological sentences. A correspondence account (both Priest's and my own) seeks to defend the view that there may be ontological contradictions, and not just those occurring in the course of semantic pathology. In this paper I seek to challenge the statement of Armour-Garb and Beall, that, “After all, the key (and, by our lights, the only) candidates for true contradictions are semantically paradoxical sentences—each of which is ungrounded, or otherwise irreducibly semantic”. While this insistence on purely semantic contradiction might not be a necessity of deflationist dialetheism, that is perhaps a question for another time; what I need to show in this regard is that dialetheism admits, perhaps more easily than previously thought, of a correspondence theory of truth.
In the second section, I will discuss the general compatibility of dialetheism with correspondence theory, here taken as a good example of a robust theory of truth which thus implies the possibility of ontological contradiction. In the third section, I will follow Priest in suggesting several candidates for ontological contradiction and provide a broad commentary on what those suggestions might imply if correct. In the fourth, I will address the view, put forward by Kroon, that utter triviality (or trivialism) is the outcome of ontological contradiction, or at least that such an outcome is not in itself disbarred thereby. This will be placed within the larger context of metaphysical versus conceptual views of contradiction.
II. Dialetheism & Correspondence
The relationship of dialetheism to deflationism has been documented (see Armour-Garb & Beall). However, that of dialetheism to correspondence theory has not, to my knowledge, been quite as deeply explored. In the first place, in “Truth and Contradiction”, Graham Priest has argued (and in this he is backed up by the aforementioned pair) that there is nothing inherent in correspondence theory that is not accommodating to dialetheism of some kind. While I will not rehearse the argument in full, I will draw attention to several important points.
Priest writes, “One should note, for a start, that if one supposes reality to be constituted solely by (non-propositional) objects, like tables and chairs, it makes no sense to suppose that reality is inconsistent or consistent. This is simply a category mistake” (Truth and Contradiction). Our theory, then, must allow for states of affairs and not just objects. Further, and this is perhaps the explicitly dialetheist component, these states of affairs must also be described by a polarity relation, that is, every state of affairs is related to the value 1 or 0. Intuitively, 1 stands for such a state obtaining and 0 for such a state failing to obtain. This part of the theory rests on the assumption that something failing to obtain still has ontological status, in other words that a “negative” state of affairs (one relating to 0) still is. As long as we do not confuse obtaining with being, this seems to me an uncontroversial move to make. The non-obtaining of a certain state of affairs, in other words, has a determinate effect on observable reality, or better, is constitutive of that reality, to the same degree that obtaining might. Both obtaining and non-obtaining are part of being. For example, my writing of this paper is the way it is because it is not the case that I'm writing it for pleasure, because I am not on fire, &c. We can describe reality both positively and negatively, in what it is and in what it is not, and I don't think we can dispense wholly with either—but that is a question for another time.
So here we have a definition, according to a type of correspondence theory, of ontological contradiction: When a state of affairs both obtains and fails to obtain at a given time, place, etc.; or, if we believe states of affairs to be atomic, it is when a state of affairs obtains and at the same time another state of affairs with exactly the same determinate qualities or relations as the first fails to obtain. For a contradiction to occur, I must have two states of affairs differing in only their polarity-relations, so that the same objects are brought into the same relations with only obtainment differing. Of course, this model only defers the philosophical question of whether such a contradiction could really exist, rather than simply being compatible with the theory. The problem would initially seem to be one of comprehension:
Our hunch is that the difficulty in seeing how a state of affairs could both obtain and fail to do so involves the mistake of trying to imagine observable states of affairs both obtaining and failing to do so—e.g., the journal's being here in front of you and its not being here in front of you. For what it is worth, we cannot imagine such states of affairs both obtaining and failing to obtain, either. (Armour-Garb & Beall)
Clearly, the impossibility of anything observable or familiar being contradictory would be a black mark against the theory. However, it is my contention that this is not the case, and as such I will now explore this possibility.
III. Contradictions in the World: Philosophical Considerations
What would be just such an observable or otherwise familiar contradiction? Following Graham Priest's suggestions in his book In Contradiction, I hold that change, including and even especially movement, is in a broad sense is contradictory. To show this we must focus in on the instant of change—in order to make things simple, I will focus on the case of movement, though the extension to other types of change follows relatively easily.
Say we have a ball moving from point A to point B. By the orthodox (consistent) account of motion, we might say that at each instant the ball is not moving, as if each instant were a snapshot. Somehow, the infinite summation of these non-moving instants yields the movement from A to B. Though it is tempting to take the infinitesimal calculus as a vindication of this view, such an explanation in fact leaves many properly philosophical questions unanswered. In the first place, it implies that movement is a mere correlation of object and position over time, in other words, that there is no state of change—movement itself is in this view extrinsic to the moving object. It is not a way out to say that movement is simply change over time, because
While there is much more that could be said about that, perhaps more important for our argument here is that such a snapshot-view (what Priest calls the “cinematic view”) of motion is highly unintuitive. It is only because the orthodox account of motion seeks to avoid contradictions at all cost that it is forced into such an unintuitive position. In contrast to this, a dialetheist account of motion can help itself to contradiction and can therefore avoid such a fate, perhaps as the following elaboration will show.
First, it would be well to acquaint ourselves with the so-called Leibniz Continuity Condition (henceforth LCC): “Any state of affairs that holds at any continuous set of times holds at any temporal limit of those times”, or, stated more intuitively, “Anything going on arbitrarily close to a certain time is going on at that time too” (Priest, In Contradiction 166). While not universally applicable, I hold with Priest that the LCC can be fruitfully applied to a number of fields or continuums, including space (and therefore motion). Here we return to our previous example of a ball moving from A to B. Splitting up motion into instants once again, we see a rater different picture from the orthodox “cinematic view”. In particular, at each instant there is intrinsic motion in the ball, meaning that even at a single instant, there is an inherent difference between a ball in motion and a ball at rest, though each be something like a snapshot. But what is the nature of this intrinsic motion?
At each instant, the ball is both entering the space, staying in the space, and leaving the space, all along the arc of its motion. Applying the LCC, we get the result that at time = 0, when the ball begins moving, it is both at rest and already leaving its space, already moving. This is because, being a limit, the starting-point is subject to the subsequent state, the state of motion. But, since it is also at rest before it begins moving (by the definition of the problem), we have a contradiction. This analysis can be extended to account for not just the endpoints or limits, but also to all motion whatsoever, so that movement (or change more generally) is a continuous contradiction. A change from p holding to ~p holding admits of at least an instant where p & ~p holds. Therefore, a change from one position to the next yields the result that at each instant there is a truth of the form p & ~p, where p is the sentence or proposition that the object is in a certain state (or place, &c.). This truth, that of the position and movement of the object, is not properly semantic—it might be either conceptual or metaphysical; I believe that there are reasons to assume the latter, though it is not absolutely clear-cut.
One of these reasons for the metaphysical interpretation, and perhaps the major one, is the Spread Hypothesis (henceforth SH), a formulation more particular to motion itself:
We suppose that over small neighbourhoods of time it is impossible to pin down states of affairs. The impossibility is not merely epistemological, but ontological: nature itself is such that it is unable to localise precisely its doings. Each instant is so intimately connected with those around it that their contents cannot but encroach. (Priest, In Contradiction 213)
This “localisation” has a clear analogue in the attempt to envision a “snapshot” that would be consistent. Suffice it to say that the SH is, even if philosophically controversial, at least scientifically valid or possible, at least for the time being. I simply draw attention to it in order to indicate that the argument presented here is not inherently opposed to scientific understanding, as might be supposed. In particular, the objection that contradiction makes us unable to understand or otherwise comprehend the world can be disposed of. Finally, this argument for change as contradiction would seem to be a vindication of the Hegelian view whereby determination in a broad sense is the outcome of a process of self-differentiation, in other words of contradiction. In particular, there is not a radical separation between what an object is now before a change and what it is after that change. It is simply an object in a state of change, something which is internal to what it is. The context or processes in which an object exists (or which exist in it!) serve to determine that object. This is but one modality of the Hegelian rejection of atomism.
We would now do well to consider another major objection to the theory outlined above, namely the belief that in fact there are no instants of time, but only intervals. If we define motion simply as distance covered over time, it is clear that there would then be no such instant. This is of no great consequence, however, because the “instant” we refer to could just as well be some interval, although usually a very very short one (even planck time!). In fact, if we apply the LCC to time itself (the legitimacy of which is dicussed in Priest's book), we get the result that each instant is actually that instant and all the instants around it. Thus the dialetheist here has a way to capture even the insight on time as an interval or as a flow; while I can't delve too deeply into this question here, I hope I have shown the objection is at least not devastating. Again, an “instant” in the context of the LCC is only meant to imply a liminal state, and not necessarily a metaphysical “point” of time.
IV. Conclusion: Metaphysical & Conceptual Contradiction
Earlier we asked the question as to whether our account would be amenable to a conceptual rather than metaphysical interpretation. To bring this into focus we turn to Priest: However, it might be suggested, to say that the world is consistent is to say that any true purely descriptive sentence about the world is consistent” (In Contradiction 159). This is likewise the case for inconsistency. It might be argued that, though our best explanation of the world at any given time might be contradictory, the world itself is not contradictory, such that God's explanation would be totally consistent. It is to this end that Kroon writes, ...the paradoxes indicate that some of our concepts are deeply defective at certain points: in particular, the rules that govern them produce inconsistent results when applied at certain limit points” (253).
Indeed, this question was not a problem for Hegel, whose philosophy was a working-out of the identity (in difference) between thinking and being. For us, however, of a more skeptical bent, the question is more difficult. In his paper, Kroon argues that once we have contradictions in the world there is no regulating principle, no reason to prefer that there be fewer contradictions rather than more. Thus there is no regulative principle which would keep us from accepting as plausible the view that, metaphysically speaking, everything is in contradiction: ...what precisely is wrong with allowing a tolerant account of entailment on which everything is both true and false since something is both true and false” (Kroon 252).
Taking this possibility alone as reason to reject ontological contradiction, Kroon writes, As I said earlier, however, the thought that the truth of trivialism is a genuine open possibility in this sense ought to strike us as bizarre and intolerable. Unlike other incredible doctrines, it deserves not an incredulous stare, but no stare at all” (252-253). In the first place, we might say that, just as in Priest's more general presentation of dialetheism, there is no reason to suppose that such a state of universal contradiction is or even could materially be the case (Kroon seems to acknowledge this). This aside, there is absolutely no a priori reason for disbelieving metaphysical triviality—if we are rationally led to the conclusion, so be it, although I don't see this ever occurring. To rule it out a priori, as Kroon does, and then to use this “bizarre and intolerable” position to rail against ontological contradiction as such, is on the whole quite irresponsible.
Thus, I hope I have shown that a dialetheist correspondence theory of truth is not ruled out by potentially unsavory results relating to ontological contradiction. A plan for further research in the area might include a more in-depth look at how the LCC can be applied to the flow of time, as well as a fuller discussion of the conceptual-metaphysical divide (and Hegel's position thereon).






Works Cited
Armour-Garb, Bradley and JC Beall. “Further Remarks on Truth and Contradiction.” The Philosophical Quarterly Vol 52. No 207 (2002): pp. 217-225. Electronic.
Kroon, Frederick. “Realism and Dialetheism.” The Law of Non-Contradiction. Eds. Graham Priest, JC Beall and Bradley Armour-Garb. New York: Oxford University Press, 2004. pp. 245-264. Print.
Priest, Graham. In Contradiction: A Study of the Transconsistent. Dordrecht; Boston: Distributors for the U.S. and Canada, Kluwer Academic, 1987. Print.
---. “Truth and Contradiction.” The Philosophical Quarterly Vol 50. No 200 (2000): pp. 305-319. Electronic.

Saturday, March 29, 2014

The Radical Implications of Dialetheism

A paper I wrote for a philosophy of logic seminar.
The Radical Implications of Dialetheism

I. Introduction

Those logics are called paraconsistent which allow for true contradictions while attempting to prevent collapsing the system into triviality, that is, without making every statement true. The development and appeal of paraconsistent logics (henceforth PL) can be traced to perhaps three major factors: technical considerations, such as what paraconsistent logic can do as against classical logic; its handling of paradoxes, particularly the Liar; and philosophical considerations relating to the possibility of contradiction.
II. Technical Aspects of Paraconsistent Logic
In PL, sentences are not simply assigned a truth-value, but rather are related to sets of values. That is, a sentence, φ, may be related to values (t, f, p), where t is true, f is false, and p is both truth and false. It is important that the value p be thought of as both true and false, not an in-between and certainly not as an undefined gap. In Priest's version of PL, there are no truth-value gaps. This means that Priest accepts the Law of Excluded Middle (LEM). That is, for any sentence A, it is true that A v ~A. Every sentence is mapped onto one of the three aforementioned value-sets by the evaluation function, v, such that v: P → {t,p,f}, where P is the set of sentences of our propositional language. In section III the question of sentences related to multiple value-sets will be raised, but for now the singly-related scheme is sufficient.
PL, since inconsistent, is semantically closed, containing its own predicates for truth, falsity, &c. Indeed, one of the primary motivations of PL is its relationship to natural language, its lack or even denial of the legitimacy of constructed metalanguages. It skirts Gödel's proof of incompleteness because that proof relies on the language's consistency. Hence, the age-old decision for consistency as against semantic completeness is here turned on its head.
In allowing for sentences to be simultaneously both true and false, questions of how to deal with such sentences immediately arises. Classical logic makes use of what is commonly called the Explosion Principle, which means that everything follows from a contradiction: A & ~A B, for any A and any B. Clearly explosion must be denied if contradictions are to be true, and if the logic is not to be trivial.
However, PL also comes with a number of losses that may at first seem quite significant. In the first place, it is easy to check that Modus Ponens (MP), Reductio ad Absurdum (RaA), and the Disjunctive Syllogism (DS) fail when paradoxical sentences are present. We will examine each of these in turn.
One of either MP or Absorption must be rejected in order to avoid Curry's Paradox. This paradox states that semantically closed theories that have both the Absorption Principle and MP lead to explosion. In particular, where T(x) is 'x is true':
      1. T(1) → A
      2. T(1) ↔ (T(1) → A)          by the T-scheme
      3. T(1) → A                          by absorption
      4. T(1)                                   MP
      5. A                                       MP
Thus, since any sentence A is provable given MP and absorption, we must dispense of one of the two. Priest decides that Absorption is relatively innocent, and therefore gets rid of MP. While this is not necessary, it is at least a reasonable decision.
Perhaps the most fundamental loss, however, is that of DS. By this I mean that the problems with MP would seem to be reducible to those with DS: p → q may be written as ~p v q, but then given p we cannot conclude q, because we may also get ~p. Furthermore, and perhaps worse, DS and contradiction together lead to explosion:
      1. A & ~A                Assumption
      2. A 1 S
      3. A v B                    2 Add
      4. ~A                         1 S
      5. B                           3, 4 DS
Finally, RaA is lost for obvious reasons.
It would seem at this point that PL loses too much to be of logical use, particularly in its loss of MP. Indeed, it would not be too great a stretch to consider the conditional of prime logical interest. It is difficult to imagine a conditional without MP, as it is difficult to imagine deductive reasoning without a properly intuitive conditional. There are, however, reasons for taking a different conditional than that commonly used in classical logic. In other words, perhaps the equation of p → q with ~p v q is what is causing the problem. Priest suggests that there may be extensions of PL that can deal with these problems, but for now we will consider the concept of quasi-validity as a solution. In particular, let us assume that MP, RaA, DS, etc. are not valid but quasi-valid, meaning they are valid in cases where the sentences in question are not dialetheias (that is, true contradictions). It can easily be checked that the problems with the aforementioned inference rules are all related to dialetheias. Hence, if we have no reason to believe there is a dialetheia involved in our reasoning, we may help ourselves to quasi-valid rules. When we discover that a dialetheia was indeed present that we did not previously realize, we must simply correct our previous arguments to dispense with the quasi-valid rules. Hence, quasi-valid rules are truth- and validity-preserving in most cases (we assume that paradoxical sentences are a relatively small part of all true sentences).
III. The Liar Paradox
One of the main attractions of PL is its ability to deal with paradoxes, the Liar chief among them. In this section, I will first present the pure Liar and show how PL might deal with it. Then, I will examine attempted constructions of a revenge Liar, and show how they raise difficult but not insoluble problems.
The pure Liar may be given as follows:
(L) (L) is false
Thus, if we evaluate (L) as true, that means it must be false and thus we have a contradiction. Alternatively, evaluating (L) as false leads to its being true, because it said of itself that it was false. Furthermore, it does not help if we admit of truth-value gaps, because then a revenge Liar can be constructed:
(L*) (L*) is not true
This version, if taken as gappy, would seem to imply that it was true, because it says of itself that it is gappy. So then it's true and therefore not gappy, and yet again we have a contradiction.
PL attempts to skirt the structural problems that give rise to the paradox by taking (L) to be simultaneously true and false. Here it will help to translate values into value-sets, a more explicit conception of truth-values in PL. A value-set is here and for the moment defined as the set of all truth-values that a sentence relates to. Thus, t can be written as {1}, f as {0}, and p as {0,1}. That is, since (L) is a dialetheia, it relates to {0,1}. So in this case there is no problem with the contradictory nature of (L), in the sense that the paradox can be contained by denial of both explosion and the LNC. Furthermore, this conclusion would seem quite intuitive, since we can say that (L) is false or that (L*) is not true without the nasty consequences associated with doing so in classical logic, or within an otherwise classical theory allowing for truth-value gaps. In fact, when confronted with (L), we are immediately tempted either to say it is both true and false or that it is neither true nor false—the second option landing us in the aforementioned problem of (L*).
But perhaps a revenge liar can still be constructed—in fact, I believe it can, given a broad enough conception of revenge. Consider the following:
(X) (X) is false only
Of course, the paraconsistent theorist may reply that (X) is false only... and also true. Philosophically, this is a view of evaluation that relies not simply on simultaneity, not on a “once and for all”, but on the ever-present possibility of extending the evaluation without necessarily rewriting what has gone before. Thus, (X) may be both false only and yet also true, where the “true” determination is added information, a revision that does not take back that which is revised. We might question whether the intuitive meaning of “only” has here been captured, but I believe there are philosophical reasons for why this is not a problem (see section IV). However, we get into a more troublesome situation if we translate (X) into the language of value-sets:
(X*) (X*) is related to value-set {0}
If (X*) is evaluated with value-set {1}, which we translate as “true”, that would mean it has value-set {0}, and therefore it has both {0} and {1}, but since each sentence can be related only to one value-set, we have the unfortunate result that 0=1. If (X*) is evaluated as {0}, that means it's false, and therefore what it was saying is true, which means it has {1}. Again, we have that 0=1. It seems likely that a paraconsistent theorist might evaluate (X*) as having value-set {0,1}, in which case it's true, in which case it's value-set is {0}, and therefore again we have the same problem. So, structurally, we may say that the problem arises when the Liar is made to explicitly define it's own evaluation, and it appears that PL does not wholly avoid the problem, ending up not just with contradiction but with wholesale triviality.
However, perhaps there is another, more radical way out of the problem, namely the possibility of a sentence relating to multiple value-sets. There are several ways to denote this, but I shall use the following method: when a sentence relates to sets {0} and {0,1} I shall say it relates to {{0},{0,1}}. In other words, the value-sets related to by a sentence I will put into another set. The implications of this, while not wholly worked out, might be as follows. First, why not just let the {0} in the above example be absorbed into the set {0,1}, so the sentence only relates to that one latter set as defined by Priest? It would appear to me that we cannot do this, because to accurately capture the difference between “false only” and “false (and true)” there ought to be a difference between the two sets. Thus, a sentence relating to {0,1} has a different truth-profile (or some such construction) than a sentence relating to {{0},{1}}. This implies a different conception of sets than the traditional set defined purely by its members. While working this out would be an absolutely enormous undertaking, I think that's the direction in which PL must go. Intuitively, a contradictory theory ought to go with some kind of contradictory or otherwise non-standard set theory.
IV. Philosophical Considerations
In the previous section I alluded to the problem of capturing the word “only”, as in the case “This sentence is false only”. With the above considerations, we have that a sentence may be false only and also true at one and the same time. The obvious question to ask is whether the “also” in fact undermines the meaning of the previous “only”. The dialetheist might say that it does not, because the subsequent “also” simply adds more information rather than somehow canceling out previous information. Put this way, the problem is structurally analogous to the status of contradictions—when we posit something that seems to directly contradict a previous statement, do we not in fact overwrite the older statement in favor of the new one? Can we (rationally or not) accept or even hold in our mind A & ~A, or in this case hold that something is only false and also that it is true as well, which would seem to be explicitly contradictory?
First, it is an evidential claim that people can or cannot hold a contradiction. While I believe it is clear and obvious that people believe many self-contradictory things, a better question would be whether that behavior is rational or not. Following Priest, I am inclined to say that non-contradiction may be one criterion for rationality among many others, and that in some cases it is rational to believe a contradiction, for example where other rational criteria are better fulfilled than by an alternative, non-contradictory belief. However, this is certainly not necessary for a dialetheist to put forward, and in fact Hegel himself believed in the contradiction of everything, propositional or otherwise. In fact, I think Hegel is a good example of a non-trivial dialetheism wherein everything is contradictory (these words have here changed from their previous technical meanings, while still, I hope, capturing the intuitions), though this is far outside the confines of the philosophy of logic.
Second, we may return to the “only” problem and see if we can make any progress. We would not say that dialetheism does not take contradiction seriously because of the “added information” argument, and structurally there is nothing different about the “only” problem, and indeed it is simply a specific linguistic example of a contradiction. What should therefore be said, rather than that dialetheism cannot understand “only”, is that non-dialetheist theories do not treat contradiction seriously, in that it is only dialetheism that takes contradiction as an existing fact not to be rejected. In most cases, “false only” means what the non-dialetheist means by it, but there are also dialetheias, such as the above Liar sentence (X), which must be taken in a contradictory way.
Alternatively, we might say, perhaps even against PL as a whole, that true and false might not in fact be defined purely negatively, that is, against each other such that true is simply not-false and false is simply not-true. Rather, a sentence relating to {0} might in fact have different effects or conceptual implications associated with that 0 than a sentence related to {0,1}. This would make sense epistemologically, because surely the effects or implications (these concepts unfortunately cannot be fully worked out here) are not, at least in some cases, the exact same. While this certainly takes us away from PL as a system, it is a necessary consideration since it does not take us away from contradiction, and attempts to deal with the same problems as does PL, only from a different angle, from a different translation of what would seem to be very similar insights. In any case, this raises many more problems the research of which might be fruitful.
V. Conclusion
PL is certainly not taking an easy way out of the problem of paradoxes. It is certainly not a cure-all for the diseases of traditional approaches to paradox, and providing a set theory appropriate for it is a massive undertaking. However, PL does exemplify the attempt to be comfortable with the universal inability to make everything consistent. In this sense, dialetheism opens the way towards reasoning with what are in the last analysis simply facts of life. In good dialetheist fashion, the rest might follow as so much more “added information”.
Works Consulted

Priest, Graham. In Contradiction: A Study of the Transconsistent. Dordrecht; Boston: Distributors for the U.S. and Canada, Kluwer Academic, 1987. Print.

---. “The Logic of Paradox.” The Journal of Philosophy. Vol 8. No 1 (1979): 219-241. Web. 16 Feb 2014.

---. “What Is so Bad About Contradictions?” The Journal of Philosophy. Vol 95. No 8 (1998): 410-426. Web. 16 Feb 2014.