Comments

  • The Ballot or...

    Now we have Vance taking over as the host of the Kirk podcast while ABC is pulling the Kimmel show for saying the killer has MAGA roots. I don't think these attempts to control the message will succeed but it is about to get ugly.
  • The Mind-Created World
    That importance is undeniable. I only suggest that such a factor is connected to other ways of thinking about our experience. It is not the only map.
  • The Mind-Created World

    Well, Aristotle puts a lot of emphasis on the being in front of you is what actually exists. We have different ideas about how that is possible, but the first thing is the encounter with such beings.

    So, that is germane to the issue at hand.
  • The Mind-Created World

    We have been down this road before regarding the "intrinsic existence" of matter in Aristotle. His speaking of matter as having "to be of a certain kind" has long complicated the discussion.

    Your synopsis excludes that part.
  • The Mind-Created World

    The mind/matter distinction was the keystone of "Neoplatonism", where matter is only to be seen as the extremity of mind informing what matter could be. The interest in opposing that view was not only to say it was the other way around.
  • The Ballot or...

    That report points to the problem of expecting a manifesto to explain actions. It also highlights how unconcerned the suspect was about killing someone as a matter of principle. That is something we do not know.

    The effort to put this in a box is all that can be known for sure so far.
  • The Ballot or...

    I don't have a ready answer for all of this.

    But there are some interesting gaps.
  • The Ballot or...

    John Brown. Malcom X.
  • The Ballot or...

    We do not know what the killer had in mind. The label "fascist" has been pinned to too many donkeys to form a shared idea. We have had experience of the MAGA version of our circumstances. Maybe they have been hoisted by their own petard. Maybe we will find out about that. Maybe not.

    What puzzles me about the MAGA message is to be told there is a war going on but also not a war. The absorption of 1/6 as a valid form of political expression versus preventing a hostile takeover by a particular cartel.

    By contrast, I submit that John and Malcolm had a clear idea about the difference between war and peace.
  • The Ballot or...

    I often wonder how the normalization of violence figures into this sort of messaging. There is a blatant political device in particular instances such as pardoning all of the participants in 1/6. But that does not add up to a possible future. The whole theater is oddly barren.
  • Could we maybe perhaps have a pinned "introduction to philosophy" thread?
    This.. is an interesting concept, at least as my mind is able to process it. Could you go into further detail? What, truly, "defies comparison" as far as something that is not lexicographically or taxonomically similar?Outlander

    For the taxonomically minded, similarities suggest identity. I do that all the time. I have a penchant for it.

    But whenever I dig into different texts, a lot of comparisons turn out to be the basis of a particular theory or the introduction of a meta-category by which all others can be surveyed. I get why both of those things happen. I make both of those kinds of judgements myself.

    Therefore, a strictly philosophical discipline should not make either of those approaches to be self-evident.
  • The Ballot or...

    This is something I was hoping to express in my comment upthread. The thoughts brewing in the young killer in the school shooting scene are not political in the way people organize to bring about a change in their circumstances. It is a different culture.
  • The Ballot or...

    The Malcolm X speech reminds me of the Introduction to John Keegan's A History of Warfare where Keegan criticizes the Clausewitz idea that war is politics by other means. Keegan strives to understand war-making as a culture of different people and not as a natural extension of pursuing political goals. War often interrupts politics.

    A ready example of this is when John Brown tried to start a war at Harper's Ferry. It was not as simple a beginning that he had hoped for, but it was a start he hoped to bring about.

    The case of Booth shooting Lincoln was in hopes of keeping a war alive. The original plot was to kill all of the leaders of Lincoln's administration.

    The civil rights era had intimations of war but also an appeal to avoid it. Otherwise, it would have all been straight up Lenin and vanguard of the proletariat.

    The Hatch decision titrated the Second Amendment into an individual right. That is different from the original idea of avoiding standing armies. Or even armies that rake.

    All the political shootings of late, whoever they target from the menu of partisan targets, are more like personal messages than a call to arms. The Kirk killing is yet another school shooting. Is that a "cultural war?" Is it not a "cultural war?" Keegan readers would like to know.
  • The Mind-Created World
    I just want to know what “object” gives me that object doesn’t. What do the marks give to object that object doesn’t already have?Mww

    What I mean by that is that the properties of space and time that we confer to existing things in an Aristotle or Aquinas set of givens is upset when those are taken to be primarily intuitions that make our experience possible. The reaction by Kant at A36/B53 shows him insisting upon a strong separation from what things are beyond our experience. But it is not an absolute separation expressed in forms of idealism he opposes. But it is a duality of his own making. In that sense, it does not give more than it takes away.
  • The Mind-Created World

    My interpretive arrangement so far has been to try and make sense of what Kant seems to not explain. When I read certain passages to be restrictions upon how to understand representations, for example, I am not claiming insight into the role of objects in Kant's system.

    The "real" involved in this case is not my opinion but a citation of where Kant answered a challenge on the matter by his contemporaries.

    Is your question about "object" such that you remove yourself as a peer capable of reviewing the text?
  • The Mind-Created World

    The passage you quote puts it in a nutshell; All instances of "objectivity" are also moments in consciousness. The emphasis upon objectivity that Wayfarer finds fault with is, by this account, already too "subjective" for some thinkers.

    Kant was wrestling with his contemporaries on the question of what was "real" in this context when discussing the existence of time outside of our experience of it. This is touched upon in my quote upthread:

    I admit the entire argument. Time is certainly something real/
    namely the real form of inner intuition. It therefore has subjective real-
    ity in regard to inner experience, i.e., I really have the representation of
    time and of my determinations in it. It is therefore to be regarded re-
    ally not as object but as the way of representing myself as object But
    if I or another being could intuit myself without this condition of sen-
    sibility, then these very determinations, which we now represent to our-
    selves as alterations, would yield us a cognition in which the represen-
    tation of time and thus also of alteration would not occur at all. Its
    empirical reality therefore remains as a condition of all our experiences.
    CPR A36/B53

    As the rest of the passage demonstrates, there is an aspect to experiencing an object that points beyond the representations of it. Kant is saying that that element is not a representation in its own right.
  • The Mind-Created World

    Many of the objections to Kant, as they played out in his lifetime and afterwards, concern his treatment of the "object" as a product of what we do. So, the effort is different from someone who looks at the attempt of explanation as a product of talking per se. I am not up to speed with Buddhist texts, but Zhuangzi put it as every attempt at division.
    So, I submit that there is an importance difference there.
  • The Mind-Created World

    That point is also made in many other places, including the issue of method put forward in my quote.

    The topic of "rational psychology" is often brought up in the CPR as a fusion of personal experiences with universal conditions. That response opposes, for instance, the presumptions of Neoplatonism and other depictions of what is rational in regard to our existence.
  • The Mind-Created World

    Reflecting upon your responses to that particular text, it prompts me to wonder how Kant's objections to the theories of a "rational psychology" relate to explanations that base themselves on some version of that.
  • Donald Trump (All Trump Conversations Here)

    As in so many matters, the permission granted in those orders is contingent upon whether or not Congress resumes the power granted to it by the Constitution. The illegality of ignoring existing statutes is not enough, although a helpful stumbling block going forward.
  • What Difference Would it Make if You Had Not Existed?

    I want to take a different approach from my previous expression of skepticism regarding measures of personal significance.

    I like 's weighing the benefits against the disappointments possibly caused by presence or absence. Some of those elements are sharply drawn by regret or pleasure. A huge amount is made ambiguous by the paths not taken. Some of that must have been wise to some extent. Some of that must surely have been a loss of benefit for each or all involved. I think it is why Aristotle said luck could not be a cause; But also why he was wrong about that.

    It seems like the speculation and fiction that most vividly describe the isolation of an individual build an enormous world in which to become isolated within.

    Maybe Dostoyevsky is the exemplar for this sort of thing because so many of his "nihilists" are so damn gregarious.
  • What Difference Would it Make if You Had Not Existed?
    I guess that I am just imagining oneself as negative space, which is only fantasised projection in the sense of removing oneself from pathways of causal chains.Jack Cummins

    I am only suggesting we do that all the time. It is an element of what we do. It is easier to imagine that our species did not exist than imagine what you propose.
  • What Difference Would it Make if You Had Not Existed?
    You say that your role doesn't exist outside of one's participation and, in a sense one's nonexistent self is a limbo phantom self. However, if one had not existed that doesn't mean that others would not have existed, so life would have been different for them.Jack Cummins

    I am not saying that. I don't have access to those kinds of facts. The awareness of different outcomes does not let me know what they might be in other cases. I did not go there.

    On one hand, I do know and remember stuff and am well aware that different choices would have meant a different life. I don't get to live that other life while living the one chosen.

    On the other hand, those choices do not give me insight into what might happen to other people absent my participation. The subtraction of my involvement runs into the problem of adding it.
  • What Difference Would it Make if You Had Not Existed?

    It is a dark question in many ways. Our way of memory weaves regret with what if X happened. Nightmares pit fatalism against desire.

    When you speak of eliminating your role in a scene, those circumstances do not exist outside of your participation. The equation grows to an impossible size. The presumed objectivity is a deeper dream.

    Think Kafka. but without all the hopeful messages.
  • The Mind-Created World

    Thank you for the clarification.

    I will take a look at Manifest Reality and see if it pulls me in. I am stingy with my time upon secondary texts and like to keep work on them in balance with engagement with primary texts, even when the secondary ones are very helpful.

    My recent interest in Kant comes from realizing that so many philosophers after him have become 'secondary sources' in their own right in regard to him. I am trying to make a separate space from all that to investigate what is said.
  • The Mind-Created World

    Do you know of a portion of Allais that suggests I have mischaracterized the debate between Allison and Strawson?
    I have been checking out secondary sources as they are appealed to by interlocutors. But I also have been trying to respond to them in the context of specific interpretations of the primary text such as those put forward by AmadeusD and Wayfarer.
  • The Mind-Created World

    I looked through what I could find of Henry Allison's writings, and he promotes a view of 'transcendental idealism' over against the view of 'transcendental realism' that he attributes to P.F. Strawson. I cannot copy and paste from the preview but here a link to Allison's book: Kant's Transcendental Idealism.

    The Preface orients the distinction in the context of the CPR. Chapter 1 introduces sharp critics of transcendental idealism on page 4 and introduces P.F. Strawson as the champion of those views on page 5. The two thinkers are diametrically opposed in this debate concerning 'things-in-themselves.'

    In the Cambridge edition of CPR, Strawson is cited in an editors' footnote for the following text:

    Elucidation.
    Against this theory, which concedes empirical reality to time but dis-
    putes its absolute and transcendental reality, insightful men have so
    unanimously proposed one objection that I conclude that it must natu-
    rally occur to every reader who is not accustomed to these considera-
    tions.20 It goes thus: Alterations are real (this is proved by the change of
    our own representations, even if one would deny all outer appearances
    together with their alterations). Now alterations are possible only in
    time, therefore time is something real. There is no difficulty in answer-
    ing. I admit the entire argument. Time is certainly something real/
    namely the real form of inner intuition. It therefore has subjective real-
    ity in regard to inner experience, i.e., I really have the representation of
    time and of my determinations in it. It is therefore to be regarded re-
    ally not as object but as the way of representing myself as object But
    if I or another being could intuit myself without this condition of sen-
    sibility, then these very determinations, which we now represent to our-
    selves as alterations, would yield us a cognition in which the represen-
    tation of time and thus also of alteration would not occur at all. Its
    empirical reality therefore remains as a condition of all our experiences.
    Only absolute reality cannot be granted to it according to what has been
    adduced above. It is nothing except the form of our inner intuition. * If
    one removes the special condition of our sensibility from it, then the
    concept of time also disappears, and it does not adhere to the objects
    themselves, rather merely to the subject that intuits them.
    The cause, however, on account of which this objection is so unani-
    mously made, and indeed by those who nevertheless know of nothing
    convincing to object against the doctrine of the ideality of space, is
    this. They did not expect to be able to demonstrate the absolute reality
    of space apodictically, since they were confronted by idealism, accord-
    ing to which the reality of outer objects is not capable of any strict proof;
    on the contrary, the reality of the object of our inner sense (of myself
    and my state) is immediately clear through consciousness. The former
    could have been a mere illusion, but the latter, according to their opin-
    ion, is undeniably something real. But they did not consider that both,
    without their reality as representations being disputed, nevertheless be
    long only to appearance, which always has two sides, one where the ob-
    ject is considered in itself (without regard to the way in which it is to be
    intuited, the constitution of which however must for that very reason al
    ways remain problematic), the other where the form of the intuition of
    this object is considered, which must not be sought in the object in it
    self but in the subject to which it appears, but which nevertheless really
    and necessarily pertains to the representation of this object.

    [Kant's footnote at "It is nothing except the form of our inner intuition. * is as follows]

    I can, to be sure, say: my representations succeed one another; but that only
    means that we are conscious of them as in a temporal sequence, i.e., accord
    ing to the form of inner sense. Time is not on that account something in it
    self, nor any determination objectively adhering to things.

    [Kant's note on the manuscript is as follows]

    "Space and time are not merely logical
    forms of our sensibility, i.e., they do not consist in the fact that we represent actual re-
    lations to ourselves confusedly; for then how could we derive from them a priori syn
    thetic and true propositions? We do not intuit space, but in a confused manner; rather
    it is the form of our intuition. Sensibility is not confusion of representations, but the
    subjective condition of consciousness."
    CPR A36/B53

    The editors' footnote #20 says (in part):

    Kant refers here to objections that had been brought against his inaugural
    dissertation by two of the most important philosophers of the period,
    Johann Heinrich Lambert and Moses Mendelssohn, as well as by the then
    well-known aesthetician and member of the Berlin Academy of Sciences,
    Johann Georg Sulzer. Lambert objected that even though Kant was correct
    to maintain that "Time is indisputably a conditio sine qua non of all of our
    representations of objects, it does not follow from this that time is unreal,
    for "If alterations are real then time is also real, whatever it might be" (letter
    61 to Kant, of 18 October 1770, 10:103-11, at 106-7). Mendelssohn also
    wrote that he could not convince himself that time is "something merely
    subjective," for "Succession is at least a necessary condition of the repre-
    sentations of finite spirits. Now finite spirits are not only subjects, but also
    objects of representations, those of both God and their fellow spirits.
    Hence the sequence [of representations] on one another is also to be re-
    garded as something objective" (letter 63 to Kant, of 25 December 1770,
    10:113-16, at 1I5). (The objection that time cannot be denied to be real
    just because it is a necessary property of our representations, since our rep
    resentations themselves are real, has continued to be pressed against Kant;
    see, for instance, P. F. Strawson, The Bounds of Sense [London: Methuen,
    1966], pp. 39 and 54.)
    — CPR page 721

    Strawson appears to hold the criteria of mind-independence as the last word on objectivity. Allison defends Kant's argument that the subjective condition is integral with the real.
  • Currently Reading

    Yes, it is a sprawling mess.
    I view it as one stop shopping. All of his stuff in one location.
  • The Mind-Created World

    I see that Pollock supports my statement that mind-independence is not a critical criterion for objectivity in Kant.
    Pollock quotes the second edition preface:

    Up to now it has been assumed that all our cognition must conform to
    the objects; but all attempts to find out something about them a priori
    through concepts that would extend our cognition have, on this pre
    supposition, come to nothing. Hence let us once try whether we do not
    get farther with the problems of metaphysics by assuming that the ob-
    jects must conform to our cognition, which would agree better with the
    requested possibility of an a priori cognition of them, which is to estab-
    lish something about objects before they are given to us.
    CPR B16

    Pollock's Introduction ends with:

    What Kant inherits from the Cartesian 'way of ideas' is the central role that the concept of consciousness, as the "mere subjective form of all our concepts," plays in metaphysical matters. This entails that objectivity becomes a crucial normative problem for his critical philosophy. But rather than inquiring into the objective reality of ideas, the vital question for Kant is: What are, and how can we arrive at, the fundamental norm of the objective validity of our judgements?Pollock, Theory of Normativity
  • The Mind-Created World

    In pointing out that feature, I am admitting a certain portion of interpretation when I emphasize a particular set of sentences above others. So, I am trying to be fair to alternative readings.
  • The Mind-Created World
    Noumena must be physical objects. That is what the system requires. Kant is just extremely careful not to say something he cannot support - therefore, these objects are beyond our ability to conceive.AmadeusD

    Please assemble a collection of citations that support this interpretation.
  • The Mind-Created World
    That's an interesting passage from Kant―I don't remember encountering it before. It seems to undercut any move towards dualism.Janus

    There is the dualism between the appearances and the objects generated through thinking. But this is nothing like the "hylomorphism" presented by Aristotle and others. The contemporary use of "mind-independence" as a criterion of objectivity is for Kant a misunderstanding of the soul caused by the limits of our experiences of the "I think":

    But without allowing such hypotheses, one can remark generally that
    if by a "soul" I understand a thinking being in itself, then it is already in
    itself an unsuitable question to ask whether or not it is of the same
    species as matter (which is not a thing in itself at all, but only a species
    of representations in us); for it is already self-evident that a thing in it
    self is of another nature than the determinations that merely constitute
    its state. But if we compare the thinking I not with matter but with the intel-
    ligible that grounds the outer appearance we call matter, than because
    we know nothing at all about the latter, we cannot say that the soul is
    inwardly distinguished from it in any way at all.
    CPR A360

    This should be read in the context of it being but one element of the chapter: "The paralogisms of pure reason" beginning at A341/B399.
  • The Mind-Created World

    Here is the whole paragraph of your citation:

    I call a concept problematic that contains no contradiction but that is
    also, as a boundary for given concepts, connected with other cognitions,
    the objective reality of which can in no way be cognized. The concept
    of a noumenon, i.e., of a thing that is not to be thought of as an ob-
    ject of the senses but rather as a thing in itself (solely through a pure un
    derstanding), is not at all contradictory; for one cannot assert of
    sensibility that it is the only possible kind of intuition. Further, this con-
    cept is necessary in order not to extend sensible intuition to things in
    themselves, and thus to limit the objective validity of sensible cognition
    (for the other things, to which sensibility does not reach, are called
    noumena just in order to indicate that those cognitions cannot extend
    their domain to everything that the understanding thinks). In the end,
    however, we have no insight into the possibility of such noumena, and
    the domain outside of the sphere of appearances is empty (for us), i.e.,
    we have an understanding that extends farther than sensibility prob
    lematically
    , but no intuition, indeed not even the concept of a possible
    intuition, through which objects outside of the field of sensibility could
    be given, and about which the understanding could be employed as-
    sertorically
    . The concept of a noumenon is therefore merely a bound-
    ary concept
    , in order to limit the pretension of sensibility, and
    therefore only of negative use. But it is nevertheless not invented arbi-
    trarily, but is rather connected with the limitation of sensibility, yet
    without being able to posit anything positive outside of the domain of
    the latter.
    CPR B310

    The boundary helps us understand what our intuitions do not give us. But Kant puts the kibosh on any attempt to relate the two domains in a wider view. The beginning of the very next paragraph is:

    The division of objects into phaenomena and noumena, and of the
    world into a world of sense and a world of understanding, can therefore
    not be permitted at all, although concepts certainly permit of division
    into sensible and intellectual ones; for one cannot determine any object
    for the latter, and therefore also cannot pass them off as objectively
    valid. If one abandons the senses, how will one make comprehensible
    that our categories (which would be the only remaining concepts for
    noumena) still signify anything at all, since for their relation to any ob-
    ject something more than merely the unity of thinking must be given,
    namely a possible intuition, to which they can be applied?
    — CPR, B311

    I recommend finishing the whole paragraph for yourself as paragraphs are the basic unit in this writing.

    To approach the difference between inner and outer, more attention needs to be spent on earlier paragraphs concerning intuition and experience. I will try to point to what stands out for me in the coming days. I have to get back to my chores.
  • The Mind-Created World

    We have both read much of what the other has not. That is a peculiar feature of this space.

    So, we could all benefit from what troubled you while reading this text.
  • The Mind-Created World

    I appreciate this translation. I cut my teeth with the Norman Kemp Smith translation fifty years ago. It was like being sent to a different planet.
  • The Mind-Created World
    Are you referring to principles, that in which resides always and only absolute certainty?Mww

    I will have to think about it in those terms. I don't want to get too far over my skis.

    In the passages I quoted, the view of Descartes and Berkeley as being childish both involve the personal being taken as a fundamental ground that is not only unproven but misses elements of experience. Kant claims his more mature approach looks for a set of conditions for the experience of the 'I think' that it is not self-evident but requires more understanding. How we visualize the boundaries seems connected to this kind of unknown. I will try to express this better in other posts.

    Your point about Kant having the last word in many places if left unchallenged is well taken.
  • The Mind-Created World

    Your observation regarding the structure of CPR is interesting. I best not put my trowel away.

    What still surprises me about the later sections is where he dismisses the either/or quality that has often been ascribed to him by later thinkers. The attempt to form the last words on an issue is yet not to have the last word. Otherwise, there would only be the silence Cratylus was said to have fallen into.
  • Could we maybe perhaps have a pinned "introduction to philosophy" thread?
    I submit that it is the differences between how philosophers use terms that undermines making a lexicon that underlies all the possible usages.

    So, for instance, I appreciate and admire efforts like the Stanford Encyclopedia of Philosophy to establish a standard of description where different thinking can be compared to each other. Such an approach is not going to illuminate what defies comparison. The latter is the motivation for many a disagreement between thinkers. Maybe there is a limit to description.
  • The Mind-Created World

    I will try to approach the passage by comparing Kant's objections to Hume with Kant's arguments against Descartes and Berkeley:

    Refutation of Idealism

    Idealism (I mean material idealism) is the theory that declares the exis
    tence of objects in space outside us to be either merely doubtful and in
    -demonstrable
    , or else false and impossible; the former is the
    problematic idealism of Descartes, who declares only one empirical as-
    sertion (assertio), namely I am, to be indubitable; the latter is the dog-
    matic idealism of Berkeley, who declares space, together with all the
    things to which it is attached as an inseparable condition, to be some-
    thing that is impossible in itself, and who therefore also declares things
    in space to be merely imaginary. Dogmatic idealism is unavoidable if
    one regards space as a property that is to pertain to the things in them-
    selves; for then it, along with everything for which it serves as a condi-
    tion, is a non-entity. The ground for this idealism, however, has been
    undercut by us in the Transcendental Aesthetic. Problematic idealism,
    which does not assert anything about this, but rather professes only our
    incapacity for proving an existence outside us from our own by means of
    immediate experience, is rational and appropriate for a thorough philo-
    sophical manner of thought, allowing, namely, no decisive judgment
    until a sufficient proof has been found. The proof that is demanded must
    therefore establish that we have experience and not merely imagina-
    tion
    of outer things, which cannot be accomplished unless one can prove
    that even our inner experience, undoubted by Descartes, is possible
    only under the presupposition of outer experience.
    CPR, B274

    Immediately following the above text is the Theorem to support it. It is a set of paragraphs that are not included in the first (or A) edition. I read this addition as an attempt to clarify language used throughout the work. One can see how the terms are carefully developed through their use.

    Kant's beef with Hume is not the skepticism the latter employed regarding the narratives produced by "reason". Kant agrees that much cannot be proved. But the limits are part of a larger understanding of experience. As quoted before:

    Thus skepticism is a resting
    place for human reason, which can reflect upon its dogmatic peregri-
    nation and make a survey of the region in which it finds itself in order
    to be able to choose its path in the future with greater certainty, but it
    is not a dwelling-place for permanent residence; for the latter can only
    be found in a complete certainty, whether it be one of the cognition of
    the objects themselves or of the boundaries within which all of our cog-
    nition of objects is enclosed.
    CPR, A758 B786
  • The Mind-Created World
    A double whammy, not only can’t we say anything about noumena, but we are confined within a world of appearances, so can’t say anything about anything else (apart from appearances), either.Punshhh

    Kant disagrees about there being nothing to say about either. He distinguishes our ignorance from a skepticism that would presume more than it can display. Here is Kant's argument with Hume on the matter:


    On the impossibility of a skeptical satisfaction of pure reason that is divided against itself.

    The consciousness of my ignorance (if this is not at the same time
    known to be necessary) should not end my inquiries, but is rather the
    proper cause to arouse them. All ignorance is either that of things or of
    the determination and boundaries of my cognition. Now if the ignor
    ance is contingent, then in the first case it must drive me to investigate
    the things (objects) dogmatically, in the second case to investigate
    the boundaries of my possible cognition critically. But that my ignorance
    is absolutely necessary and hence absolves me from all further investi
    gation can never be made out empirically, from observation, but only
    critically, by getting to the bottom of the primary sources of our cog
    nition. Thus the determination of the boundaries of our reason can
    only take place in accordance with a priori grounds; its limitation, how
    ever, which is a merely indeterminate cognition of an ignorance that is
    never completely to be lifted, can also be cognized a posteriori, through
    that which always remains to be known even with all of our knowledge.
    The former cognition of ignorance, which is possible only by means of
    the critique of reason itself, is thus science, the latter is nothing but
    perception, about which one cannot say how far the inference from it
    might reach. If I represent the surface of the earth (in accordance with
    sensible appearance as a plate, I cannot know how far it extends. But
    experience teaches me this: that wherever I go, I always see a space
    around me in which I could proceed farther; thus I cognize the limits of
    my actual knowledge of the earth at any time, but not the boundaries
    of all possible description of the earth. But if I have gotten as far as
    knowing that the earth is a sphere and its surface the surface of a sphere,
    then from a small part of the latter, e.g., from the magnitude of one de-
    gree, I can cognize its diameter and, by means of this, the complete
    boundary, i.e., surface of the earth, determinately and in accordance
    with a priori principles;' and although I am ignorant in regard to the ob-
    jects that this surface might contain, I am not ignorant in regard to the
    magnitude and limits of the domain that contains them.

    The sum total of all possible objects for our cognition seems to us to
    be a flat surface, which has its apparent horizon, namely that which
    comprehends its entire domain and which is called by us the rational
    concept of unconditioned totality. It is impossible to attain this empir
    ically, and all attempts to determine it a priori in accordance with a cer-
    tain principle have been in vain. Yet all questions of our pure reason
    pertain to that which might lie outside this horizon or in any case at
    least on its borderline.

    The famous David Hume was one of these geographers of human
    reason, who took himself to have satisfactorily disposed of these ques
    tions by having expelled them outside the horizon of human reason,
    which however he could not determine. He dwelt primarily on the prin
    ciple of causality, and quite rightly remarked about that that one could
    not base its truth (indeed not even the objective validity of the concept
    of an efficient cause in general) on any insight at all, i.e., a priori cogni
    tion, and thus that the authority of this law is not constituted in the least
    by its necessity, but only by its merely general usefulness in the course
    of experience and a subjective necessity arising therefrom, which he
    called custom. Now from the incapacity of our reason to make a use
    of this principle that goes beyond all experience, he inferred the nullity
    of all pretensions of reason in general to go beyond the empirical.

    One can call a procedure of this sort, subjecting the facta of reason to
    examination and when necessary to blame, the censorship of reason. It
    is beyond doubt that this censorship inevitably leads to doubt about all
    transcendent use of principles. But this is only the second step, which is
    far from completing the work. The first step in matters of pure reason,
    which characterizes its childhood, is dogmatic. The just mentioned
    second step is skeptical, and gives evidence of the caution of the power
    of judgment sharpened by experience. Now, however, a third step is still
    necessary, which pertains only to the mature and adult power of judg
    ment, which has at its basis firm maxims of proven universality, that,
    namely, which subjects to evaluation not the facta of reason but reason
    itself, as concerns its entire capacity and suitability for pure a priori
    cognitions; this is not the censorship but the critique of pure reason,
    whereby not merely limits but rather the determinate boundaries of
    it - not merely ignorance in one part or another but ignorance in
    regard to all possible questions of a certain sort - are not merely sus
    pected but are proved from principles. Thus skepticism is a resting
    place for human reason, which can reflect upon its dogmatic peregri
    nation and make a survey of the region in which it finds itself in order
    to be able to choose its path in the future with greater certainty, but it
    is not a dwelling-place for permanent residence; for the latter can only
    be found in a complete certainty, whether it be one of the cognition of
    the objects themselves or of the boundaries within which all of our cog-
    nition of objects is enclosed.

    Our reason is not like an indeterminably extended plane, the limits of
    which one can cognize only in general, but must rather be compared
    with a sphere, the radius of which can be found out from the curvature
    of an arc on its surface (from the nature of synthetic a priori proposi
    tions), from which its content and its boundary can also be ascertained
    with certainty. Outside this sphere (field of experience) nothing is an
    object" for it; indeed even questions about such supposed objects con
    cern only subjective principles of a thoroughgoing determination of
    the relations that can obtain among the concepts of understanding in
    side of this sphere.
    CPR, A758 B786

    The above quote also supports 's observations concerning the role of boundaries in rational activities.