2

Considering many scientists who believe that humans are nothing special, how do we trust our logic that much that makes it 'The' Logic?

For me, it's being very contradictory, how a non-special being just trust himself so much? To what extent a non-special being has to trust his reasoning? How trusting his own logic(Which indicates he isn't special) isn't considered special enough?

Doesn't make this thesis a logically incoherent thought?

I want to know why this thesis is already too common despite its clear inconsistency.

Not_Here
  • 2,831
  • 1
  • 19
  • 40
Ismaeil Ghouneim
  • 133
  • 2
  • 2
    Hi, welcome to Philosophy SE. Please visit our [Help Center](https://philosophy.stackexchange.com/help) to see what questions we answer and how to ask. It is unclear how you arrived at the premise of the question. We do not have "the logic" but multiple logics, and there is a history of controversies surrounding them, see [What are the differences between philosophies presupposing one Logic versus many logics?](https://philosophy.stackexchange.com/q/37276/9148) – Conifold Feb 23 '18 at 20:34
  • From all that we know we're the most special beings that are around, that's assuming contact with aliens hasn't been made yet ;-) – jjack Feb 24 '18 at 17:16
  • Do you see the irony in saying "'viewing logic as definitive' is inconsistent and incoherent"? The reasoning you give behind the question is really superficial, yes a biologist will probably say that a human is a mammal, not different in many respects from any other mammal, but there are quite a few where we are different. Do you think that a biologist would believe that a population of raccoons would be able to build a space shuttle and launch it into orbit? That makes us special or unique. Humans have rational minds that allow us to reason about things, we call those abilities logic. – Not_Here Feb 24 '18 at 17:29

3 Answers3

1

It's possible for a flawed ("non-special") agent to arrive at objective ("special") facts/truths. For example, Newton held all kinds of occult beliefs (of which at least some are probably false!), but this did not prevent him from discovering objective facts about the observable universe, e.g. Newton's laws of motion.

So, IMO, there's no contradiction between the claim that our reasoning ability may be in some sense flawed (e.g. limited), and the claim that our reasoning ability can (still) help us discover some important facts.

Alex Sotka
  • 147
  • 6
  • OK, but mere possibility should not convey confidence. So the OP's objection stands. Though he has overstated it. There is no contradiction, just a lack of reason to believe this. –  Feb 27 '18 at 17:44
  • Well, I think we can be confident that our flawed/limited reasoning can yield *some* objective facts (i.e. reliable predictions) -- because we've already discovered many such facts. On the other hand, I would agree that (using our flawed reasoning) we clearly can't be confident of discovering *all* (or even a significant fraction of) the facts. – Alex Sotka Feb 27 '18 at 21:45
  • OK, so what is the connection between 'we can know something' and all logic must agree with ours. I can't interpret 'makes it 'The' logic' as merely meaning that it might produce some truth. To that extent, this is simply not an answer to the question as given. –  Feb 28 '18 at 02:15
  • If you have some Logic-X that helps you discover some facts, and no other known systems of reasoning that can be said (or at least agreed upon) to discover any (or any more) facts, then it's not out of place to refer to Logic-X as "The Logic", IMO. You seem to imply that "The Logic" should be reserved for a method that yields *all* the facts -- but this definition is arbitrary, and indeed becomes vacuous if such a method does not exist. – Alex Sotka Feb 28 '18 at 02:53
  • That is a bizarre premise. Animals somehow discover very useful things how to find food, where the water is, etc. Termites discover things we don't know without logic. So there is more than one method for discovering some facts. But those do not qualify as logic. Only human logic put together as a whole is generally considered to be logic. Our notion of the power of logic is not just that is might get us some facts. We surely act like it is the only proper way to ever handle facts, despite these other obvious phenomena. That clear selective blindness on our part still calls for an explanation –  Feb 28 '18 at 03:11
  • But you have no evidence that they do. Only that they have some method that gets them some facts. *You then assume* I mean that they must have logic, that there is only one way to get facts and they must share it. But this is a baseless assumption. If you don't get my point by now, there is no hope. You are just not answering the question, because it is about this assumption that you have just made, and that we all make automatically. –  Feb 28 '18 at 03:19
  • You seem committed to a specific interpretation of "logic" as "human logic". But there is no reason why we cannot talk about "human logic", "animal logic", etc, as "reasoning systems" -- which to me reflects the usage of the term in the question. In this sense, IMO, we can say that our "reasoning system" is "The reasoning system", because it is the best (known) at helping us find facts (e.g. animals don't fly to the moon), and we also don't know if a better one exists. – Alex Sotka Feb 28 '18 at 04:21
  • All of that is true, and none of it has anything to do with what I was saying. In practice, you automatically assumed that animals must have part *of the logic that we have*, not of their own kind. That assumption is really common, and it is what the question is about. It is not about whether logic works, as your answer imagines, it is about why we assume (falsely as you finally note) that logic is singular. At this point, I am tired of having the point missed, and I am not willing to say this over again yet another way. –  Feb 28 '18 at 19:46
  • Animals have logic that works with limited success. I agree that their logic is not "our" logic (one of my replies was incorrectly worded). We have (different) logic that works with much more success. The success is the reason to trust it -- and the "extent" of this success is the extent to which it can be trusted. I am sorry you are tired, but it's because you pursued an irrelevant tangent that missed the gist of my original point. – Alex Sotka Mar 05 '18 at 01:45
  • "Missing the point" is the insult you started with. – Alex Sotka Mar 30 '18 at 08:59
  • No, an observation is not an insult. Your answer does not in any way address the question as asked. You can insist all you want and that won change. I have tried to direct you toward the question. I am sorry if you see actually getting you to answer the question you claim to answer as an irrelevant tangent. But very few people would agree. I wish there were a way to block comments on this site. –  Mar 30 '18 at 14:34
1

Our logic is the valid logic because it has been abstracted from reality. There is only one exception, namely the quantification over infinite sets. That is invalid logic, as has been recognized by famous mathematicians long ago already. As an example I quote Hermann Weyl:

Brouwer opened our eyes and made us see how far classical mathematics, nourished by a belief in the "absolute" that transcends all human possibilities of realization, goes beyond such statements as can claim real meaning and truth founded on evidence. According to this view and reading of history, classical logic was abstracted from the mathematics of finite sets and their subsets. (The word finite is here to be taken in the precise sense that the members of such set are explicitly exhibited one by one.) Forgetful of this limited origin, one afterwards mistook that logic for something above and prior to all mathematics, and finally applied it, without justification, to the mathematics of infinite sets. This is the Fall and Original sin of set theory even if no paradoxes result from it. Not that contradictions showed up is surprising, but that they showed up at such a late stage of the game! [Hermann Weyl: "Mathematics and logic: A brief survey serving as a preface to a review of the philosophy of Bertrand Russell", American Mathematical Monthly 53 (1946) 2-13]

However this facet of presently used logic is rather inconsequential because all results of research concerning infinite sets are irrelevant for any real application.

Hilbert7
  • 1
  • 1
  • 1
  • 30
  • "All results of research conferning infinite sets are irrelevant for any real application." This is likely false unless you have in mind an extremely narrow notion of 'real application'. (In other words, Harvey Friedman and the reverse mathematicians would like to have a word with you!) – possibleWorld Feb 24 '18 at 19:37
  • There is no application of set theory. The real physical world does not offer any stage for the appearance of finished infinity. The only application of set theory could be in mathematics. Alas mathematics contradicts set theory, for instance in case of limits. See as one of many examples Fraenkel's Tristram Shandy in the simplified version of Scrooge McDuck, p. 250 of https://www.hs-augsburg.de/~mueckenh/Transfinity/Transfinity/pdf. – Hilbert7 Feb 24 '18 at 21:55
  • Trying to understand, when you say "Our logic is the valid logic because it has been abstracted from reality", in what sense do you mean "because"? Is logic valid because it's an abstraction of some objective facts? Or because it's an abstraction that is able to avoid the "messy-ness/unknowable-ness" of reality? Can there be a "valid" reasoning system without abstracting from reality? – Alex Sotka Feb 24 '18 at 23:01
  • @Alex Sotka: SeeWeyl: "classical logic was abstracted from the mathematics of finite sets". Even the symbols of set theory and logic are very closely related (intersection - and, union - or). Finite sets and numbers are abstracted from reality. And I said "because", because reality is "valid"; it is consistent. Our existence is the proof. – Hilbert7 Feb 25 '18 at 08:00
  • I'm not sure how one can apply the term "consistent" in the same way to observed reality as you would to a system of reasoning. But even if you could, how can we be certain that a particular (man-made) abstraction of a consistent reality is itself consistent? – Alex Sotka Feb 25 '18 at 09:33
  • I used "consistent" in the sense that every state of the world generates precisely one other state without ever crashing. Same holds for finitary logic. When extending this logic to infinite sets however, we encounter crashes like the following: The sequence f(n) = |{1, 2, 3, ..., n}|/|{n+1, n+2, n+3, ...}| = 0, 0, 0, ... has limit 0 in mathematics but a limit greater than 1 in set theory (because the set of natural numbers can be exhausted such that the denominator vanishes). – Hilbert7 Feb 25 '18 at 11:20
  • 1
    You might want to get off your hobby horse and ACTUALLY ANSWER A QUESTION in a way that is remotely relevant to the asker.... –  Feb 27 '18 at 16:18
0

From a certain POV, we have to think that because of what logic is.

From a neo-Intuitionistic perspective, a la Steven Kleene, mathematics, and logic in particular, is the full elaboration of the set of 'intuitions' or assumptions about ideas that all humans ultimately share. It is the set of things to which we naturally respond with the calm acceptance of the proven, and for which the only challenge to belief is sheer complexity.

There may be some delving about to make us recognize them, but as Plato noted in the Theatetus, they bubble up from inside, or they fail to. And those for whom they fail to are then deprived of a certain part of human cultural experience.

But that means that whatever does not at some level follow the rules of logic and or mathematics is incomprehensible to humans as a whole. So we don't question logic because generally, when we needed to, we are set to be thwarted. If we admitted logic did not in any way apply to a situation, we would just be sunk anyway.

Humans are often very herd-like beings, and we tend not to care much for what cannot be shared with other humans. So human thoughts that cannot be wedged into accepted logic tend not to matter, unless they pay off in some demonstrable way.

We do make the effort to build up artificial logical approximations to the parts of the world where it pays off to defy our logic. We may find them endlessly fascinating. Many intelligent people in our culture fought with quantum mechanics very hard. Others among us are amazed by our own unconscious behavior or with that of other animals that do not share the logic of our conscious process and yet survive very well.

But we can still only share experiences of those things with one another with great effort and to a limited degree. A large segment of the populace will always consider them a waste of time.