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Constraints, Concept , Kant & Space

  1. Jun 20, 2012 #1
    In a recent thread, language was described as an activity where: a set of rules is used to define constrains on the world. For instance the word car limits they type of objects in the world which are likely to be denoted by the word car because one might not normally expect one to call a house (RVs aside) a car. Math and music were also given as examples of languages. Some psychologists say that our language both influences what we think and our ability to think.

    In the critique of Pure reason, Kant, questioned the idea that all concepts could be represented in terms of constraints because if we did not have some concept a prior how would we express those constraints. From the critique of pure reason:

    ”4. Space is represented as an infinite given quantity. Now it is quite true that every concept is to be thought as a representation, which is contained in an infinite number of different possible representations (as their common characteristic), and therefore comprehends them: but no concept, as such, can be thought , as if it contained itself an infinite number of representations. Nevertheless, space is so thought, (for all parts of space exist simultaneously ad infinitum). Consequently, the original representation of space is an intuition a priori, and not a concept”

    However, Kant’s argument does not convince me. Why can’t I infer space from my senses.

    P.S. As I mentioned before. The section I quoted from Kant does not match the project Gutenberg version.

    My Sources: Basic Writings of Kant, Allen W. Wood, ISBN 0-37575733-3
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  3. Jun 20, 2012 #2
    I think Kant would argue that our concepts or knowledge outstrips the information that sense experience can possibly provide. Since the content of some concepts seems to outstrip anything we could have gained from experience, I think he would argue (and I find his arguments convincing) that those concepts must be innate or a priori. This is the so-called “poverty of stimulus” argument (i.e. “torrential output” from “meagre” input), which claims, on empirical grounds, that:
    The implication here (a sound one, in my opinion), is that our biologically-determined properties of the mind/brain play a crucial role in determining what and how we perceive the “external” world, since the perceptual knowledge we attain vastly transcends any environmental input. Some argue, however, that he may jumped the gun a bit with our concept of 3-D space. We can go beyond that type of space using math but I'm guessing he would argue that is innate also. A prominent modern follower of Kantian-type view is Chomsky, I think. He argues that:
  4. Jun 21, 2012 #3


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    It is Kant's strong dichotomisation of objective cognitions into concepts and intuitions - what I would call general ideas and particular ideas - which is the questionable step to me.

    If an idea is a constraint imposed on our impressions so as to sharpen them, then there is no problem in having ideas that vary from the highly general (cats) to the highly restrictive (my black cat Kiki). But this just means there is a quantitative difference, not a qualitative difference between a Kantian concept and intuition.

    Kant wanted to distinguish between objective rational truths that would be necessarily true in all possible worlds (ie: concepts) and truths like intuitions that might only be true of some actual worlds (yet not then false, just a value-less proposition, in perhaps other worlds). So he had a larger motivation for the distinction.

    But again, for me, that is an over-complication because possibility and necessity seem quite enough to produce worlds. And if there also happened to be a variety of worlds - unlikely I would say - then we would just invoke some kind of chance factors to explain that. Like multiverse cosmology does these days.

    So Kant starts off with some sensible epistemic basics, like we are only modelling reality, and that our concepts constrain our sensations. But it quickly all gets confusing as he over-complicates.

    From a modern point of view, we would say that brains simply inherit their primitive notions of space (and time). So there is an inference, an empirical forming of a useful idea, that has happened as a matter of evolutionary learning. It is innate, but still ultimately learnt. And being innate - apparently rational - gives us a head start in life because we don't have to create a useful idea from scratch when we are born.

    And then also rather undermining any claims Kant made about the rational basis of our intuitions about space is the fact that our modern notions of space(time) have become so different from the Cartesian/Newtonian concepts that Kant was talking about. Space can be considered substantial, multiple, bounded, etc, contra to Kant's intuitions.

    [edit: connecting to the language issue, you can see also that there is a genetic level encoding of space as a concept and then a sociocultural level one. So two levels of "language" involved there - one that evolves its concepts slowly, the other which can change its concepts within a matter of generations.]
    Last edited: Jun 21, 2012
  5. Jun 22, 2012 #4
    I'm not sure that the distinctions of concepts/intuitions (Kant) or reasons/'grows in the mind' (Chomsky) are clear enough here. It seems to me that our impulses for actions (which is the crux of this) arise from:

    1) Instinct: our genetic a priori - that is, evolved characteristics
    2) Intuition: learned behaviours, manifest from the subconscious
    3) Rationality: conscious reasoning from the evidence i) of our senses
    ................................................................ii) of our physical wellbeing (homeostasis)
    ................................................................iii) of our feelings

    The Kant/Chomsky reasoning is too narrow and confused for my liking!
  6. Jun 22, 2012 #5


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    In order to analyze anything you need to describe it. Description means language and quantization of form. That form can correspond indirectly to something of the uncountable, but the form is discrete in terms of its representation. In other other words, in language descriptions: everything is somehow mapped to the finite.

    If you can't constrain you can't analyze which means you can't do any kind of analysis or synthesis which ends up translating into not being able to do pretty much anything.

    What the actual forms correspond to in terms of our senses and ultimately our entire perception whether from our five senses or otherwise is another question, but in line with the above, it is required for analysis - a discretization scheme is required to be able to perform analysis.

    You can not analyze what you can not describe and you can not describe something that has no linguistic representation.
  7. Jun 22, 2012 #6
    1) In Kant’s time I don’t know if they knew about evolution. The Greeks knew about it but it may have been forgotten (as the church was dominant in that time). It is interesting that (as far as I know) Bertrand Russell did no talk much (or perhaps at all) about an "evolution a prior". I presume since Russell was arguing against the idealist he was rejecting any notion that any part of our knowledge came from our mind (aside from introspection) as this could put in doubt an independent existence of the phsyical world.

    2) Kant did mention evolution. To understand his view on this, the following quote from the critique of pure reason (same version as above) may be helpful:

    --Chapter: Transcedental Doctrine of Elements, Section: First Part. Transcedental Aesthetic

    3) Before I comment on this part I’ll give you an chance to expand on it to better clarify what you mean.

    I agree that Kant is difficult. As to what degree his work is worth the struggle of learning: I have not read enough of it, nor have I had enough time to digest it to know. I do think though that that his ethics had more of an impact then his stuff about mental things such as he discussed in, “The Critique of Pure Reason”.
  8. Jun 26, 2012 #7
    It's an interesting quote, particularly the way in which he seems to talk about 'sensibility' as learning through exposure to things (which I read as inductive experience through the senses) rather than deductive, objective rationale. I would liken this to early learning, which is a very subjective, trial-and-error type of experience when compared to academic learning through texts.

    I agree with him that this type of 'sensibility' learning corresponds with 'intuitions' as a basis for future actions, and seems to me to be a fundamental part of everyday human life experience: we are not as much the objective analytical creatures as we make ourselves out to be!!

    I disagree, however, with 'all thought therefore must...go back to intuitions': this seems to me to be an illogical step/non-sequitur since the intuitions explanation does not preclude the possibility of there being other origins of thought, such as those I mentioned before (genetic or rational). As you say, though, he was a man of his time and the theory of evolution as beautifully rendered us by Darwin was not available in his time!!
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