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Is the supposition that the future resembles the past falsifiable ?

Is the supposition that the future resembles the past falsifiable ?

I read the question rather differently: can any amount of past and present evidence falsify a claim about the future, insofar as it still remains the future? Of course, past and present evidence can give us ample reason to doubt certain claims that might be made about the future: but could it ever demonstratively disprove such claims? I'm not at all sure that it could. An instance of an F that isn't G can falsify the proposition that all Fs are currently G, but it can't similarly falsify the proposition that all future Fs will be G. Current evidence tells us about what is currently true or false, and to project this onto the future for the purposes of falsification is as problematic -- no more so, but also no less so -- as projecting it onto the future for the purposes of verification. And, as David Hume showed us more than 250 years ago, that there are genuine grounds for concern about the latter. The 'problem of induction' suggests that there is a certain logical circularity in any such attempt at projection, be it positive or negative.

But then, let's not forget how Karl Popper presented his doctrine of falsificationism. It was supposed to be an alternative to inductivism, one that didn't actually need to rely (at least not overtly) on any problematic assumptions concerning the uniformity of nature. So I don't think Popper would be especially concerned about the challenge that you raise. He could acknowledge that such a supposition isn't falsifiable -- and consequently would presumably conclude that it isn't scientific -- but he could then just carry on regardless. I'm not sure that, within the terms of his own programme, this would qualify as a problem at all.

As it stands, the supposition is hopelessly vague. You would need to make it more precise, I would think, to render it falsifiable: what are the relevant respects in which past and future are to be compared? What are the time periods we are talking about? And what counts as resemblance or lack thereof in each of these respects? Without answers to these questions, it's hard to know what would count as evidence pro or con. For example, can the averge price-to-earnings ratio of the S&P500 be relevant to the sought falsification? If so, what's the relevant past period that the future might resemble or not? How far must this ratio stray from the past range for there to be non-resemblance? How long must the deviation last? Are we to look at annual averages or daily fluctuations? Does discontinuation of the index count as non-resemblance? Is non-resemblance of this ratio sufficient to falsify the supposition, or must there be other respects as well in which the future is different? Etc.

Is it true that knowledge is the same as truth

Is it true that knowledge is the same as truth

You are asking whether it is true that T=K (knowledge and truth are the same). From your asking this, I conclude that you don't know whether T=K. If truth and knowledge were the same, then lack of knowledge would be lack of truth. So, assuming T=K is true, we derive the conclusion that T=K is false.

Better then to suppose that knowledge and truth are not the same.

And of course they aren't. Something may be true and yet not be known by many or not be known by anyone at all. For example, take the following two sentences: "with optimal play, white can always win in chess" and "it is not the case that, with optimal play, white can always win in chess". One of these sentences is certainly true; but no one yet knows which one it is. (Or, if anyone does now, they haven't told me, so I don't know which is true.)

You are asking whether it is true that T=K (knowledge and truth are the same). From your asking this, I conclude that you don't know whether T=K. If truth and knowledge were the same, then lack of knowledge would be lack of truth. So, assuming T=K is true, we derive the conclusion that T=K is false. Better then to suppose that knowledge and truth are not the same. And of course they aren't. Something may be true and yet not be known by many or not be known by anyone at all. For example, take the following two sentences: "with optimal play, white can always win in chess" and "it is not the case that, with optimal play, white can always win in chess". One of these sentences is certainly true; but no one yet knows which one it is. (Or, if anyone does now, they haven't told me, so I don't know which is true.)

I have been reading Robert Nozick’s Philosophical Explanations (a difficult text

I have been reading Robert Nozick’s Philosophical Explanations (a difficult text indeed) and have a question about his theory of knowledge; specifically, Nozick concedes to the knowledge skeptic that we cannot know, say, if we are a brain in a vat on Alpha Centauri (our experience of the world would be identical, says the skeptic, to what it is now, so we cannot know); but he then also notes that it does not follow that I cannot know, say, that I am typing on my computer. If I understand correctly, Nozick holds that my belief that I am typing tracks the fact that I am typing; I would not have the belief that I am typing if I were not typing. This, however, seems problematic to me; it seems to beg the question, i.e. assume the “fact” that I am typing is indeed a fact. Isn’t this what we precisely do not know according to the skeptic? What if I see a perceptual distortion, for example, a pencil wobbling like rubber when I place it between my thumb and index finger and quickly move it back and forth? My...

This doesn't seem at all clear. First of all, the argument assumes that, to know whether we know, on Nozick's account, we would have to know whether a certain counterfactual is true. But this isn't obvious. Water is H2O, but it doesn't follow that, to know whether something is water, you have to know whether it is H2O. Similarly, even if knowledge is (say) Nozick-style tracking, it does not follow that, to know whether you know, you have to know whether you track Nozick-style. That might follow if Nozick's account is construed as providing some kind of conceptual analysis, but even then there are issues that tend to go under the heading "The Paradox of Analysis".

Second, even if the foregoing is waived, I don't see why we can't know "whether the subjunctive condition Nozick deems necessary for knowledge is fulfilled". Surely we do have lots of knowledge about possibility, necessity, and counterfactuals. Of course, the epistemology of modal knowledge is a vexed issue, but so is the epistemology of everything else.

Well spotted! Nozick holds that, in order for you to know p, it must be the case that, if p were false, you wouldn't believe p. This condition is not fulfilled when p is "it is not the case that I am a brain in a vat on Alpha Centauri being stimulated to have my present experiences": if p were false (if I were a brain in a vat on Alpha Centuri being stimulated to have my present experiences), then I would nonetheless be believing p. But this condition may well be fulfilled when p is "I am typing." It is fulfilled if, were I not typing, I wouldn't believe that I am. With this move, Nozick takes himself to have shown at least how knowledge is possible: it's possible that I am really typing and that, if I weren't typing, I wouldn't believe that I am. But do I know that I am typing or do I not? Well, according to Nozick, this depends on what I would believe if I weren't typing now. Nozick assumes that there's a definite answer to this question, a fact of the matter. But, even if we grant this,...

Is Kant's "Critique of Pure Reason" still valuable in any philosophical and non

Is Kant's "Critique of Pure Reason" still valuable in any philosophical and non-historical sense to think about knowledge and its conditions of possibility? André C.

As with other great works in the history of philosophy, Kant's Critique of Pure Reason -- the single greatest work of philosophy ever written, in my view -- is valuable more for the questions it poses and the ways it develops for pursuing these questions than for the answers. These questions and methods are understood and reflected in the best work done by philosophers today. Still, much current work in philosophy is not at this level -- mistakes of the kinds Kant exposed are still frequently made, esp. ones that are so "natural" to our ordinary ways of thinking. (For example, it is very natural to believe that you just know the temporal order of the events in your mental life ... until someone presses you to explain how a being with a plurality of mental items in her mind could possibly get from these the notion of time and some specific ordering of her mental items in time.)

Kant explored so much new ground in this book, pioneering the language needed in this exploration as he went along, that his exposition is certainly not as clear and elegant as it could be. Similar points can be made about Einstein and Gödel, say, whose pioneering achievements we now generally read in more elegant later formulations. With Kant, I think, we should stick to the original text (though good secondary literature can be very helpful in reading this text). The reason is that philosophy is so much more "messy" and unframed than physics and mathematics. Here what one is trying to do, and what would count as success, are not given in advance of the inquiry, but constantly in play during the work itself. As a result, there is much more controversy (than in the cases of Einstein and Gödel) about what exactly Kant thought of himself as achieving, and (relatedly) much greater interest in reconstructing the path on which Kant arrived at a specific picture of what he was trying to accomplish. And then there is the further bonus that the Critique of Pure Reason conveys an excitement of discovery, of gaining a wholly new view of the problem of human knowledge, which no later treatment could possibly convey.

one book with you for the rest of your life...?" Well, I would take this book. No contest. Yes, I have read it before, and not just once or twice. But I am sure I will never read it or teach it without new learning and wonder.

As with other great works in the history of philosophy, Kant's Critique of Pure Reason -- the single greatest work of philosophy ever written, in my view -- is valuable more for the questions it poses and the ways it develops for pursuing these questions than for the answers. These questions and methods are understood and reflected in the best work done by philosophers today. Still, much current work in philosophy is not at this level -- mistakes of the kinds Kant exposed are still frequently made, esp. ones that are so "natural" to our ordinary ways of thinking. (For example, it is very natural to believe that you just know the temporal order of the events in your mental life ... until someone presses you to explain how a being with a plurality of mental items in her mind could possibly get from these the notion of time and some specific ordering of her mental items in time.) Kant explored so much new ground in this book, pioneering the language needed in this exploration as he went along...

Can there ever be a meaningful distinction in science between the "unknown" and

Can there ever be a meaningful distinction in science between the "unknown" and the "unknowable"? I see no reason why science should not,in 100,000 years or so, unlock what now seem to be unknowable questions like the nature of a Prime Mover, if he exists, simply by accruing more and more knowledge of the universe. We know pretty much what happened a trillionth of a second after the Big Bang and we acquired this knowledge in about 100 years so why assume everything before that is unknowable? Surely the scientific method would insist that this is "presently unknown". Is it that metaphysics and the persistence of religious belief color our approach? Is "unknowable" even a valid term in philosophy, and, if so, what definitive, unassailable examples are there of it (which would also apply, say, 100,000 years from now)? Thanks in advance.

Let's begin by distinguishing two senses in which something might be said to be unknowable. In some cases something is said to be unknowable because it isn't the kind of thing about which, in principle, knowledge could be had. For example, do you know the minimum number of hairs a man must have on his head to escape being bald? Well, there is no such minimum number to be known or discovered, because the concept of baldness is too vague for this. Do you know what time of day it is now on the sun (Wittgenstein)? Would you be happier dead? Again, there's nothing to be known or discovered in these regards. Philosophers have said about such cases that "there is no fact of the matter." Let us set these cases aside, because they are not the ones that interest you.

In the cases that interest you, there is a fact of the matter. And the claim is then either that it is impossible for us (human beings including all future generations) to know this fact or even, more dramatically, that it is in principle impossible for any beings to know this fact.

I believe that, contrary to what you are suggesting, there can be and there really are unknowables of both these kinds. Let us begin with the first kind of case, with knowledge others might have but we humans can never acquire.

Physicist believe that the universe is expanding and that some parts of it are moving away from us (or we from them, this does not matter) at extremely high speeds. According to their theory, it is physically impossible for us ever to catch up with those objects so as to examine aspects of them that leave no trace in their emissions. Intelligences living in those parts (if there are such) can know those details, but human beings cannot ever possibly find them out.

You may object that perhaps our physicists are wrong. Perhaps future scientists will invent a form of space travel that is much faster than the speed of light and would allow human beings to travel to those parts and examine them closely. This objection is sound, but it misses its mark. It shows that what we now believe to be unknowable may yet turn out to be knowable. The objection does not show that there could not be anything unknowable. After all, present physics might also turn out to be right on this point, in which case human beings can really never possibly know various details about those fast receding parts of the universe.

Now let's proceed to unknowables of the other kind, facts that no one could possibly ever know. Some mathematical and perhaps also some physical facts are so complex that there isn't enough stuff in the universe to represent or to encode them; it is in principle impossible to know the first 10^1000 prime numbers, for example. Some experiences are unattainable for any physically possible conscious life form: No one can know what it is like to be at the center of the sun, because there is simply too much heat and pressure to introduce and maintain there the complex molecules necessary for conscious life. No one can know the last thoughts of beings whose planet was sucked into a black hole (whose gravitational pull, so physicists tell us, no information-bearing emissions can overcome). No one can know what laws of physics held true in the universe a billion years before beings like oneself came into existence (I'm a bit skeptical here about the knowledge you claim about the moment of the Big Bang -- knowledge that relies on extrapolating present natural laws backward in time). No one can know through which of two little holes some minimal particle or photon reached a sensor, because any way of acquiring this information would have interfered with its reaching the sensor.

Again, some of these examples are disputable. Perhaps it will turn out that some of these things can be known after all. But your question, as I understood it, was whether there might be unknowables in the second sense. And to this question the answer is yes. There might well be. And the progress of science may well teach us that things we deemed knowable are in fact unknowable (just as it may indeed also teach us that things we deemed unknowable are knowable).

This leaves us with a thought close to Socrates. A good part of intellectual progress consists in knowing what we can and what we cannot know. Or in the words of modern philosopher Clint Eastwood: "A man's got to know his limitations." (And women, too.)

Let's begin by distinguishing two senses in which something might be said to be unknowable. In some cases something is said to be unknowable because it isn't the kind of thing about which, in principle, knowledge could be had. For example, do you know the minimum number of hairs a man must have on his head to escape being bald? Well, there is no such minimum number to be known or discovered, because the concept of baldness is too vague for this. Do you know what time of day it is now on the sun (Wittgenstein)? Would you be happier dead? Again, there's nothing to be known or discovered in these regards. Philosophers have said about such cases that "there is no fact of the matter." Let us set these cases aside, because they are not the ones that interest you. In the cases that interest you, there is a fact of the matter. And the claim is then either that it is impossible for us (human beings including all future generations) to know this fact or even, more dramatically, that it is in principle...

I don’t know if I’m right about this, but I often have the impression that

I don’t know if I’m right about this, but I often have the impression that philosophers have traditionally regarded the means of knowledge as some kind of obstacle to getting at ‘reality in itself’, as if the aim of scientific inquiry should be to somehow strip away the interferences of our own minds, bodies, perceptual capacities, language, etc., in order to unveil the world ‘in itself’, free of all ‘anthropomorphic colouring’. Whenever in my life I have occasionally found time to give myself over to speculative musings (and I’m not sure if it’s been too often, or not nearly enough!), I have often been tempted by a different idea, only then to drop it again as scientifically suspect, if not straightforwardly mythical or mystical. However, I’ve often wanted to put it to a professional philosopher to see what he or she would make of it. I’m sure it’s not at all original, and perhaps you can tell me which historical philosophers have held a similar view, but I’m mainly interested in whether or not anyone...

Immanuel Kant comes pretty close to articulating the points you make here.

In one of his last writings, Kant tells the story of a man who stands in front of the mirror with his eyes closed (or almost closed). Asked what he is doing there, the man responds that he wants to see what he looks like when he is asleep.

The story is funny because the man is attempting the impossible: When his eyes are really shut (as in sleep), then he will see nothing and, in particular, will not see what he looks like. And when his eyes are just a little bit open, then he will see himself alright, but with his eyes slightly open (not as in sleep).

The morale of this funny story is that the desire to know what the world is like apart from our faculties of knowledge is incoherent: We want to know, hence engage our faculties of knowledge, and yet know without these faculties of knowledge and presumably even without any faculties of knowledge at all.

The story is meant to reconcile us to the fact that, as far as we can conceive, all our knowledge must be conditioned by our mental faculties. We're supposed to understand that the "true" knowledge we sometimes dream of is not merely (like eternal life) beyond our reach, but incoherent (like a round square).

Our science can be objective, distinguish truth from falsity, give us a comprehensive picture of the world. Still, this picture must always be our picture, dependent on, and conditioned by, our mental faculties of inquiry and representation. This insight may feel like a disappointment. Kant sought to take this sense of disappointment away by showing that knowledge could not possibly be anything more than this.

Immanuel Kant comes pretty close to articulating the points you make here. In one of his last writings, Kant tells the story of a man who stands in front of the mirror with his eyes closed (or almost closed). Asked what he is doing there, the man responds that he wants to see what he looks like when he is asleep. The story is funny because the man is attempting the impossible: When his eyes are really shut (as in sleep), then he will see nothing and, in particular, will not see what he looks like. And when his eyes are just a little bit open, then he will see himself alright, but with his eyes slightly open (not as in sleep) . The morale of this funny story is that the desire to know what the world is like apart from our faculties of knowledge is incoherent: We want to know, hence engage our faculties of knowledge, and yet know without these faculties of knowledge and presumably even without any faculties of knowledge at all. The story is meant to reconcile us to the fact...