>> On Wed, Nov 10, 2010 at 8:37 PM, Brent Meeker <[email protected]> >> wrote: >>> If you are a determinist then all beliefs are causally >>> connected to facts (facts about your brain, perception, the world...). If >>> the facts and the belief are congruent and they are causally connected then >>> they are justified_true_beliefs. >>> >> >> If the facts and the beliefs are congruent, then the beliefs are true. I >> agree. >> >> However, just because Belief X is causally connected to Fact Y doesn't >> meant that Belief X is justified. >> >> The question of justification is how do you *know* that Belief X is >> causally connected to Fact Y? >> >> It may be a fact (Fact Z) that Belief X is causally connected to Fact >> Y, but how do you justify your belief in Fact Z? >> >> And then, how do you justify your belief in your belief that Belief X >> is causally connected to Fact Y? And then, how do you justify your >> belief in your belief in your belief that Belief X is causally >> connected to Fact Y? And so on. >> >> The problem is that the only facts that we have direct access to are >> facts about our current beliefs. It is a fact that I believe this. >> BUT, I can't say for sure that it's *true* that we only have direct >> access to facts about our current beliefs. >> >> It's just what I believe at this moment. Though, I can't even say for >> certain that I believed it an hour ago. I believe I did, but I can't >> justify that belief. >> >> From our current beliefs we infer the existence of other facts, but >> why should we believe that our current beliefs are true or that our >> process of inference is correct? >> >> Skepticism doesn't say that there are no true beliefs. It just says >> that we can never justify them. >> > > Depends on what you consider justification. We use common sense and other > theories of the world all the time.
But what is the ultimate significance of our use of common sense and other theories? Why do we care about usefulness? Evolution? Then why did we evolve this way instead of some other way? Physical laws and initial conditions? Then why do we have the physical laws and initial conditions we have instead of some others? And so on. Subjectively you feel that there’s some significance. But ultimately it’s just the way things are, and there is no reason why they are this way instead of some other way. > They are justified by the fact that > they usually successful in making predictions. Not always, but mostly. This brings us full circle back to Meillassoux's essay. Why do you believe that success in making predictions justifies your theories? Some form of probabilistic reasoning, right? But how do you know that your application of such reasoning is legitmate in this case? Let me just quote Meillassoux’s essay here and try to present the core of his argument, without requiring you to read the whole thing: "The problem of induction as formulated by Hume consists fundamentally in asking how we can justify that the future should resemble the past. Goodman, following Hume, fully affirms that we simply cannot do so: this justification is impossible by rational means. [...] The problem of induction, as soon as it is formulated as the problem of the effective necessity of laws, issues in an avowal of the defeat of reason, because nothing contradictory can be detected in the contrary hypothesis of a changing of constants. For reason does not seem to be capable of prohibiting a priori that which goes against the purely logical necessity of noncontradiction. But in that case, a world governed by the imperatives of reason, would be governed only by such logical imperatives. Now, this would mean that anything non-contradictory could (but not must) come to pass implying precisely the refusal of all causal necessity: for causality, on the contrary, asserts that amongst different, equally conceivable events certain of them must come to pass rather than others. This being so, we would indeed have to agree that in a rational world everything would be devoid of any reason to be as it is. A world which was entirely governed by logic, would in fact be governed only by logic, and consequently would be a world where nothing has a reason to be as it is rather than otherwise, since nothing contradictory can be perceived in the possibility of such a being-otherwise. [...] Hume's discovery, according to our account, is thus that an entirely rational world would be by that very token entirely chaotic: such a world is one from which the irrational belief in the necessity of laws has been extirpated, since the latter is opposed in its very content to what constitutes the essence of rationality. [...] I would affirm that, indeed, there is no reason for phenomenal constants to be constant. I maintain, then, that these laws could change. One thereby circumvents what, in induction, usually gives rise to the problem: the proof, on the basis of past experience, of the future constancy of laws. But one encounters another difficulty, which appears at least as redoubtable: if laws have no reason to be constant, why do they not change at each and every instant? If a law is what it is purely contingently, it could change at any moment. The persistence of the laws of the universe seems consequently to break all laws of probability: for if the laws are effectively contingent, it seems that they must frequently manifest such contingency If the duration of laws does not rest upon any necessity, it must be a function of successive 'dice rolls', falling each time in favour of their continuation or their abolition. From this point of view, their manifest perenniality becomes a probabilistic aberration - and it is precisely because we never observe such modifications that such an hypothesis has seemed, to those who tackled the problem of induction, too absurd to be seriously envisaged. [...] Beginning to resolve the problem of induction comes down to delegitimating the probabilistic reasoning at the origin of the refusal of the contingency of laws. More precisely, it is a matter of showing what is fallacious in the inference from the contingency of laws to the frequency (and thus the observability) of their changing. This amounts to refusing the application of probability to the contingency of laws, thereby producing a valuable conceptual distinction between contingency understood in this radical sense and the usual concept of contingency conceived as chance subject to the laws of probability. Given such a distinction, it is no longer legitimate to maintain that the phenomenal stability of laws compels us to suppose their necessity. This permits us to demonstrate that, without serious consequence, real necessity can be left behind, and with it the various supposedly insoluble enigmas it occasioned. In short, Hume's problem becomes the problem of the difference between chance and contingency. [...] Now, if this [probabilistic] reasoning cannot be justified, it is because there does not truly exist any means to construct a set of possible universes within which the notion of probability could still be employed. The only two means for determining a universe of cases are recourse to experience, or recourse to a mathematical construction capable of justifying unaided the cardinality (the 'size') of the set of possible worlds. Now, both of these paths are equally blocked here. As for the empirical approach, obviously no-one — unless perhaps Leibniz's God — has ever been at leisure to survey the entire set of possible worlds. But the theoretical approach is equally impossible: for what would be attempted here would be to affirm that there is an infinity of possible worlds, that is Vernes'y of logically thinkable worlds, which could only reinforce the conviction that the constancy of just one of them is extraordinarily improbable. But it is precisely on this point that the unacceptable postulate of our 'probabilist sophism' hinges,for I ask then: of which infinity are we speaking here? [...] [T]here is no reason, whether empirical or theoretical, to choose one infinity rather than another, and since we can no longer rely on reason to constitute an absolute totality of all possible cases, and since we cannot give any particular reason upon which to ground the existence of such a universe of cases, we cannot legitimately construct any set within which the foregoing probabilistic reasoning could make sense. This then means that it is indeed incorrect to infer from the contingency of laws the necessary frequency of their changing. So it is not absurd to suppose that the current constants might remain the same whilst being devoid of necessity, since the notion of possible change - and even chaotic change, change devoid of all reason - can be separated from that of frequent change: laws which are contingent, but stable beyond all probability, thereby become conceivable. [...] Now, we can see in what way the critique of the probabilist sophism permits us to challenge such a topos in a new way. For such reasoning is only legitimate if we suppose the existence of a determinate set (whether finite or infinite) of possible universes, obtained through the antecedent variation of the givens and constants of the observable universe. Now, it appears that there are no legitimate means of constituting the universe of possibles within which such reasoning could make sense, since this means, once more, could be neither experimental nor simply theoretical: as soon as one frees oneself from the imperatives of experience, in the name of what principle can one limit, as the Anthropic Principle implicitly does, the set of possible worlds to those obtained solely by the linear variation of constants and variables found in the currently observable universe, and in whose name do we limit such a set of worlds to a determinate infinity? In truth, once the possible is envisaged in its generality, every totality becomes unthinkable, and with it the aleatory construction within which our astonishment finds its source. The rational attitude is not, in actual fact, to seek an explanation capable of responding to our astonishment, but to trace the inferential genealogy of the latter so as to show it to be the consequence of an application of probabilities outside the sole legitimate field of their application." > If I left my watch on the dresser last night I can usually find it there in > the > morning. To imagine that it would be a better justification of this to have > some complete, deterministic theory of everything is the fallacy of the > misplaced concrete. First, I’m not arguing that it would be a better justification. So I’m not sure how this connects to my post. And second, what is it that would be incorrectly reified by such a belief? The deterministic laws? Believing that such laws were in some sense “real” just because of their completeness and predictive success would be to succumb to the fallacy of the misplaced concrete? It seems to me that Meillassoux is arguing against that exact fallacy. That there is no "concrete" necessity behind the orderliness of our observations. > On 11/11/2010 10:43 AM, Rex Allen wrote: >> Bryan Caplin: >> “Put succinctly, if we have knowledge we must accept beliefs only >> because we understand them to be true; but if determinism is correct, >> then we automatically accept whatever beliefs that our constituent >> micro-particles impose on us.“ > > If determinism is true...nothing whatsoever follows. It's like saying "God > did it." Unless you can specify the initial conditions and the causal laws > of evolution, it's nothing but a form of words. If determinism is true, there are no specific predictions about the physical world that can be made as a result. But there are facts about our universe that can be logically inferred from the definition of "determinism". And Caplan’s point is one of those facts. So even without knowing the specific initial conditions and causal laws, one can still draw general conclusions that would hold *if* the universe is deterministic (and if your starting assumptions and processes of inference are valid). -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.
