I meant to say that taking intuition of space and time as a process of my perception raises the question of how "objective" it is. That ties into Kant's beef with Berkeley who treats space as an experienced phenomenon. Kant argues that it is, rather, an a priori condition for sensibility: — Paine

Space and time are big issues in philosophy, and I'm not an expert. But I do agree that we do not experience space as a phenomenon. I wouldn't say that it is a condition for sensibility, but rather a principle of interpretation of the phenomena.
I'm afraid, though, that I simply have no grasp of what he means by saying that it is an intuition. Is it something like a brute fact?
My other problem is how we can conceive of space without objects in it, when we cannot conceive of what I call objects without their spatial dimensions and position in relation to each other. The mathematical representation of space - as a graph with three axes and an origin seems to separate space from what it contains, but I think that is an illusion. The graph has no meaning except as a way of locating objects.
I realize that a priori means before experience, but what does the metaphor mean here? (I realize that it is a deeply embedded metaphor that has become a regular way of speaking. But I detect an ambiguity here, whether before means a stage in a process or a position in a structure, supporting or enabling experience. My metaphor for understanding the a priori is framework vs content, setting up the rules of a game vs playing the game. I think that that Kant thinks that the a priori tells us something about how the world is - about possible worlds.

The principle that throughout dominates and determines my Idealism, is on the contrary: "All cognition of things merely from pure understanding or pure reason is nothing but sheer illusion, and only in experience is there truth." — Prolegomena to Any Future Metaphysics, page 374, or page 69 in the linked document

My word. That is a surprise. He sounds like a radical 20th century analytic philosopher.

Space and time, together with all that they contain, are not things nor qualities in themselves, but belong merely to the appearances of the latter: up to this point I am one in confession with the above idealists. But these, and amongst them more particularly Berkeley, regarded space as a mere empirical presentation that, like the phenomenon it contains, is only known to us by means of experience or perception, together with its determinations. I, on the contrary, prove in the first place, that space (and also time, which Berkeley did not consider) and all its determinations a priori, can be known by us, because, no less than time, it inheres in our sensibility as a pure form before all perception or experience and makes all intuition of the same, and therefore all its phenomena, possible. It follows from this, that as truth rests on universal and necessary laws as its criteria, experience, according to Berkeley, can have no criteria of truth, because its phenomena (according to him) have nothing a priori at their foundation; whence it follows, that they are nothing but sheer illusion; whereas with us, space and time (in conjunction with the pure conceptions of the understanding) prescribe their law to all possible experience a priori, and at the same time afford the certain criterion for distinguishing truth from illusion therein. — Prolegomena to Any Future Metaphysics, page 374, or page 69 in the linked document

This just defeats me. Perhaps you can paraphrase it for me?
".... space ..... can be known by us, because .... ... and makes all intuition of the same (i.e. all perception and experience) ....possible."
Well, yes, with reservations.
Does "space .... and all its determinations a priori," mean Geometry?
What does "(sc. space)inheres in our sensibility as a pure form before all perception" mean?
"... experience, according to Berkeley, can have no criteria of truth, because its phenomena (according to him) have nothing a priori at their foundation"
"...space and time .... prescribe their law to all possible experience a priori, and at the same time afford the certain criterion for distinguishing truth from illusion therein."
That's roughly the definition of the a priori, using a metaphor, which I think clouds his meaning. The kind of law that is a prescription defines the possibility of breaking it. But if the a priori defines possibility, there is no possibility of breaking it.
I would need some argument to accept that space and time are the criterion for distinguishing truth and illusion. I would have thought that non-contradiction and identity would be essential - or is that what he means by the "pure conceptions of the understanding."?

I, too, am learning from this discussion. — Paine

That's all right, then.

I will try to respond to some other of your comments but need to get back to painting a specific appearance. — Paine

I see from later comments that you are painting a door. That's a hard task, because a vertical surface promotes drips. I was, however, rather surprised. I always thought that the only way you could paint an appearance was by painting a picture.

It's true that by existing, we effect things, and perception influences our surroundings. The observer effects what it observes.

Quite right about the 'a' being a footnote and not an indefinite pronoun. One of the hazards of copying and pasting text here. I try to clean those up as a rule. With Kant, it is like herding cats.

Your points about how the use of appearance became more strictly expressed through later works is well taken. Thank you for connecting the A379 language to that of B157. The corresponding pages of the Editors Notes are 739 and 727. For others following the linked edition. It is from those notes that I remembered the passage from Prolegomena above.

I have been reading what is said in A379 through the lens of the Refutation of Idealism given in the B edition. I was thinking that the specificity is still focused upon the difference between what is given through inner and outer intuitions when the Theorem states:

The mere, but empirically determined, consciousness of my own existence proves the existence of objects in space outside me — B275

That also, as you said:

tacitly supports Descartes’ sum while not being quite so supportive of the “problematic” idealism explicit in the cogito ergo… part — Mww

I will have to mull over whether the Theorem is "not so supportive" or a thumb in the eye to the other part. I have been leaning toward the latter.

One element in both the A and B editions that is fairly consistent is the term 'transcendental object.' It is used 28 times in the text (according to my find-in- page function). The meaning as the "unknown ground" for both the inner and outer seems to be preserved at each passage.

I will continue to think about the role of the "I am" that you illuminate.

Space and time are big issues in philosophy, and I'm not an expert. But I do agree that we do not experience space as a phenomenon. I wouldn't say that it is a condition for sensibility, but rather a principle of interpretation of the phenomena.
I'm afraid, though, that I simply have no grasp of what he means by saying that it is an intuition. Is it something like a brute fact? — Ludwig V

Before trying to respond to that, it would help to know which thinkers you are well versed in. Kant was using the language of his contemporaries. I know some things about them and their differences but studied Ancient Greek philosophy before and more rigorously than turning to Kant's time. I am still a stranger in a strange land.

All the thinkers Kant responded to had different ways of framing what is intuition, phenomena, ideas, logic, and categories. They were arguing within a set of parameters. The problems we have looking in from outside is that we cannot share that set without problems of translation.

With that said, where are you coming from?

I'm fairly typical of people educated in the 20th century English-speaking philosophical tradition. But with an emphasis on ordinary language philosophy and Wittgenstein (especially the later Wittgenstein) and Locke, Berkeley and Hume, so very sceptical of analytic philosophy. Some Ancient Greek Philosophy, but mostly early to middle period Plato and Aristotle's ethics. Some continental philosophy, especially existentialism. I was not active philosophically from 2000 to 2020 so considerably out of date.

All the thinkers Kant responded to had different ways of framing what is intuition, phenomena, ideas, logic, and categories. They were arguing within a set of parameters. The problems we have looking in from outside is that we cannot share that set without problems of translation. — Paine

I'm not surprised. There's always a delicate balance to be struck there.

Thank you for the report. I will work on painting a picture.

Here's a question I would like to put to you.

I found the following in SEP - Kant

The two-aspects reading attempts to interpret Kant’s transcendental idealism in a way that enables it to be defended against at least some of these objections. On this view, transcendental idealism does not distinguish between two classes of objects but rather between two different aspects of one and the same class of objects. For this reason it is also called the one-world interpretation, since it holds that there is only one world in Kant’s ontology, and that at least some objects in that world have two different aspects: one aspect that appears to us, and another aspect that does not appear to us. That is, appearances are aspects of the same objects that also exist in themselves. So, on this reading, appearances are not mental representations, and transcendental idealism is not a form of phenomenalism.

That makes a lot of sense to me, and would resolve many of the objections that I've been raising. What, if anything, do you think of it?

The writer of the article is assuming that things-in-themselves are present whether we experience them or not. That is not what Kant says in the quote given in the preceding section:

What may be the case with objects in themselves and abstracted from all this receptivity of our sensibility remains entirely unknown to us. — A42/B59–60

When the writer says in section 3,

In some sense, human beings experience only appearances, not things in themselves. — ibid

experience is taken to be a matter of contact with either one or the other kind of object. The narrowness of that reading is what I argued against in my comment to you here. There is a ground where the inner and outer are thought to be in one world, but it is not presented as only things outside of us. The writer is unknowingly presenting a two-object interpretation: Objects in the world and our representations of them.

The writer continues the misunderstanding in 3.1. What is being called a "two object interpretation" by the "so-called Göttingen review by Christian Garve" is what Kant vehemently denounced in the Prolegomena passage I quoted previously

“….if the critique has not erred in teaching that the object should be taken in a twofold meaning,
namely as appearance or as thing in itself…”
(Bxxvii)

In other words, the Critique does teach the twofold aspect, but not of the object. It is the two-fold aspect of the human intellectual system as laid out in transcendental philosophy. It is by means of that system that an object is treated as an appearance in accordance with sensibility on the one hand, or, an object is treated as a ding an sich on the other, in accordance with pure speculative reason.

All that is perceived must exist, but it does not follow that only the perceived exists. Because it is absurd to claim only the perceived exists, insofar as subsequent discoveries become impossible, we are entitled to ask….for that thing eventually perceived, in what state was that thing before it was perceived?

Why? To defeat Berkeley’s “esse est percipi”, as prescribed by that “dogmatic” idealism predicated on subjective conditions alone.

I believe the briefest explanation provided by Kant on the role of intuition as a possibility for experience is where he distinguishes intuition from thinking. In the section titled: On the original-synthetic unity of
apperception (at B132). The terms used there are related to one another and thus given definition.

At B137, the term object is introduced:

Understanding is, generally speaking, the faculty of cognitions. These consist in the determinate relation of given representations to an object." An object, however, is that in the concept of which the manifold of a given intuition is united. Now, however, all unification of representations requires unity of consciousness in the synthesis of them. Consequently the unity of consciousness is that which alone constitutes the relation of representations to an object, thus their objective validity, and consequently is that which makes them into cognitions and on which even the possibility of the understanding rests. — CPR B137

It is in the context of this unity where the dual aspect referred to by comes in to play. The passage continues to show how space is not just a concept:

The first pure cognition of the understanding, therefore, on which the whole of the rest of its use is grounded, and that is at the same time also entirely independent from all conditions of sensible intuition, is the principle of the original synthetic unity of apperception. Thus the mere form of outer sensible intuition, space, is not yet cognition at all; it only gives the manifold of intuition a priori for a possible cognition. But in order to cognize something in space, e.g., a line, I must draw it, and thus synthetically bring about a determinate combination of the given manifold, so that the unity of this action is at the same time the unity of consciousness (in the concept of a line) and thereby is an object (a determinate space) first cognized. The synthetic unity of consciousness is therefore an objective condition of all cognition, not merely something I myself need in order to cognize an object but rather something under which every intuition must stand in order to become an object for me, since in any other way, and without this synthesis, the manifold would not be united in one consciousness. — ibid. B138 underlined emphasis mine

All that is perceived must exist, but it does not follow that only the perceived exists. Because it is absurd to claim only the perceived exists, insofar as subsequent discoveries become impossible, we are entitled to ask….for that thing eventually perceived, in what state was that thing before it was perceived? — Mww

Yes, we know, or can discover, what manner of existence things have for us. We can also ask what manner of existence they could have for other percipients or absent any percipients at all—but about that question we can only assess what seems most plausible given our understanding of our own experience.

Can’t argue with any of that. Except that absent any percipients thing; you seem alright with it, so I’ll leave it be. I know what you mean.

On other words, the Critique does teach the twofold aspect, but not of the object. It is the two-fold aspect of the human intellectual system as laid out in transcendental philosophy. It is by means of that system that an object is treated as an appearance in accordance with sensibility on the one hand, or, an object is treated as a ding an sich on the other, in accordance with pure speculative reason. — Mww

That points to the structure of the Critique establishing limits as starting places before building upon them to introduce new thinking. For instance, the conditions described at B132 to B138 are observed but qualified by B165 or the Result of this deduction of the concepts of the understanding:

We cannot think any object except through categories; we cannot cognize any object that is thought except through intuitions that correspond to those concepts. Now all our intuitions are sensible, and this cognition, so far as its object is given, is empirical. Empirical cognition,
however, is experience. Consequently no a priori cognition is possible for us except solely of objects of possible experience.* But this cognition, which is limited merely to objects of experience, is not on that account all borrowed from experience; rather, with regard to the pure intuitions as well as the pure concepts of the understanding, there are elements of cognition that are to be encountered in us a priori. Now there are only two ways in which a necessary agreement of experience with the concepts of its objects can be thought: either the experience makes these concepts possible or these concepts make the experience possible. The first is not the case with the categories (nor with pure sensible intuition; for they are a priori concepts, hence independent of experience (the assertion of an empirical origin would be a sort of generatio aequivoca [spontaneously generated]. Consequently only the second way remains (as it were a system of the epigenesis48 of pure reason): namely that the categories contain the grounds of the possibility of all experience in general from the side of the understanding. But more about how they make experience possible, and which principles of its possibility they yield in their application to appearances, will be taught in the following chapter on the transcendental use of the power of judgment.

From the footnote at the asterisk:

* So that one may not prematurely take issue with the worrisome and disadvantageous consequences of this proposition, I will only mention that the categories are not restricted in thinking by the conditions of our sensible intuition, but have an unbounded field, and only the cognition of objects that we think, the determination of the object, requires intuition; in the absence of the latter, the thought of the object can still have its true and useful consequences for the use of the subject's reason, which, however, cannot be expounded here, for it is not always directed to the determination of the object, thus to cognition, but rather also to that of the subject and its willing. — CPR B165 to B167 underlined emphasis mine

The reference to epigenesis separates this view from Descartes and Berkeley who only offered versions of the real as reductions to a single ground for experience.

I'm sorry I've taken so long to reply. Off-line life, which we choose to call real, intervened. I need to take more time to work through what you have posted. So, for the moment, a thought about something else.

Hence let us once try whether we do not get farther with the problems of metaphysics by assuming that the objects must conform to our cognition, which would agree better with the requested possibility of an a priori cognition of them, which is to establish something about objects before they are given to us. — CPR, Bxvi

My puzzlement about what "conform" means continues. It occurred to me that taking into account what Kant may have been reacting to might be illuminated by looking again at Aristotle. (It is possible that he actually had Aristotle in mind, but I'm not historian enough even to suggest that.)

His (sc. Aristotle's) primary investigation of mind occurs in two chapters of De Anima, both of which are richly suggestive, but neither of which admits of easy or uncontroversial exposition. In De Anima iii 4 and 5, Aristotle approaches the nature of thinking by once again deploying a hylomorphic analysis, given in terms of form reception. Just as perception involves the reception of a sensible form by a suitably qualified sensory faculty, so thinking involves the reception of an intelligible form by a suitably qualified intellectual faculty (De Anima iii 4, 429a13–18). According to this model, thinking consists in a mind’s becoming enformed by some object of thought, so that actual thinking occurs whenever some suitably prepared mind is “made like” its object by being affected by it.

SEP - Aristotle's Theory of Mind
If I remember right, Aristotle thinks that our minds cannot have any inherent form, because that would prevent it being able to grasp any external object that had the same or similar form. So Kant's Copernican move makes sense. Possibly. But I think the comparison helps.

In other words, the Critique does teach the twofold aspect, but not of the object. It is the two-fold aspect of the human intellectual system as laid out in transcendental philosophy. It is by means of that system that an object is treated as an appearance in accordance with sensibility on the one hand, or, an object is treated as a ding an sich on the other, in accordance with pure speculative reason. — Mww

This seems very plausible to me. But since it is a question of how the object is treated, I wonder what ground there is for talking of two different kinds of object. Put the question this way, what determines whether a given object is treated in accordance with sensibility or in accordance with pure speculative reason. Or is it like the difference between smells and sounds, where the difference is guaranteed by the nature of the "intuition"?

We can also ask what manner of existence they could have for other percipients or absent any percipients at all — Janus

I'm not at all sure that the latter alternative will stand up to Berkeley's "master argument". (He concludes too much in his conclusion that the tree doesn't fall unless someone perceives it. The tree falls and if some one had been there, they would have perceived it.)

All good, except….

….the conditions described at B132 to B138 are observed…. — Paine

….I think “observed” is out-of-place here. The listed pagination concerns the analytic of logical functions, not the aesthetic of empirical givens.

I have the feeling you appreciate the precision in recounting the text, with the same precision with which it was written, and meant to be understood.

But, as with , I know what you mean.
————-

….what determines whether a given object is treated in accordance with sensibility or in accordance with pure speculative reason. — Ludwig V

A given object is always treated in accordance with both sensibility and reason. What determines that such should be the case, is nothing but this particular version of speculative metaphysics.

An object in general, or a merely possible object, without regard to any particular one, constructed by the understanding hence that object not given to the senses but still related to possible experience, is called an empirical conception and is treated a priori by pure theoretical reason. For example, justice, beauty, geometric figures, deities, and the like.

That object without any empirical content whatsoever, and no possibility of it hence entirely unrelated to possible experience, both constructed and treated by pure speculative reason, and is called a transcendental object or idea. For example, the categories, mathematical principles, inferential syllogisms, and the like.

These are not proper objects, of course, not existent things, but merely indicate a position in a synthesis of representations in which they are contained. Rather than being objects as such, they are objects of that to which they stand in relation. Object of Nature is an appearance, object of intuition is a phenomenon; object of understanding is a conception; object of reason is an idea. Explanatory parsimony, if you will.

That’s what I get out of it, anyway. Loosely speaking.

Correction noted. Explanatory parsimony rules the day. I may use that tight wad in other shops.

That’s what I get out of it, anyway. Loosely speaking. — Mww

It may be a loose way of speaking, but it make sense to me. Thanks. Very helpful.

I will pursue my Buddha nature by not commenting on the SEP article.

The receptivity of perception in Aristotle can be seen as a parallel to that of the intuition of sensibility. But where Kant directly rebukes Aristotle is over his use of logic at A268/B324. The disparaging remark occurs in the section titled: On the amphiboly of the concepts of reflection through the confusion of the empirical use of the understanding with the transcendental at A 260/B316. This topic concerns your question:

Put the question this way, what determines whether a given object is treated in accordance with sensibility or in accordance with pure speculative reason — Ludwig V

Kant demonstrates how the categories and grounds are different for the two. The sources for the difference has already been established by previous deduction. The "conformity to objects" of Bxvi is the issue at the quote provided previously:

Now there are only two ways in which a necessary agreement of experience with the concepts of its objects can be thought: either the experience makes these concepts possible or these concepts make the experience possible. — CPR B165 to B167 underlined emphasis mine

The confusion Kant works to undo in the amphiboly is achieved by defeating Leibniz and Locke with one sweeping roundhouse kick:

The conditions of sensible intuition, which bring with them their own distinctions, he [Leibniz] did not regard as original; for sensibility was only a confused kind of representation for him, and not a special source of representations; for him appearance was the representation of the thing in itself, although distinguished from cognition through the understanding in its logical form, since with its customary lack of analysis the former draws a certain mixture of subsidiary representations into the concept of the thing, from which the understanding knows how to abstract. In a word, intellectualized the appearances, just as Locke totally sensitivized the concepts of understanding in accordance with his system of noogony (if I am permitted this expression), i.e., interpreted them as nothing but empirical or abstracted concepts of reflection. Instead of seeking two entirely different sources of representation in the understanding and the sensibility, which could judge about things with objective validity only in conjunction, each of these great men holds on only to one of them, which in his opinion is immediately related to things in themselves, while the other does nothing but confuse or order the representations of the first. — CPR A270/B326

If you continue reading to B344, the object of the Preface has been put in its transcendental place:

The concept of the noumenon is therefore not the concept of an object, but rather the problem, unavoidably connected with the limitation of our sensibility, of whether there may not be objects entirely exempt from the intuition of our sensibility, a question that can only be given the indeterminate answer that since sensible intuition does not pertain to all things without distinction room remains for more and other objects; they cannot therefore be absolutely denied, but in the absence of a determinate concept (for which no category is serviceable) they also cannot be asserted as objects for our understanding. — ibid B344

*Paine checks his pockets to see if he still has enough left over to buy lunch*