Of course. There should be as many interpretations as there are folks that bother with it. What he wanted the interpretation to be, should be singular, no matter how many folks bother. Which was the whole point of grounding the theory in logic, insofar as if these premises are the case, then that conclusion follows necessarily. One can, then, grant the conclusions given those premises on the one hand, yet refute the logic by denying those premises ever were the case on the other. In which case, Kant hasn’t been refuted, he’s been replaced. — Mww

I read the scientists conducting the remote experiments on time and space in different locations on the earth based on TI of CPR. It wouldn't be imaginable if one insisted to stay in 1781 and inside the fence of CPR word by word for interpreting and understanding Kant.

As with most sources, whether Fox or CNN, whether the BBC or Talk TV, one has to make a personal judgement as to whether the source makes a logical and reasoned case. — RussellA

Any popular media based information will be flatly rejected as propaganda in all philosophical discussions unless proved and verified otherwise. :)

From the Wikipedia article on Transcendental arguments, which presumably uses transcendental logic, Kant used transcendental arguments to show that sensory experiences would not be possible if we did not impose their spatial and temporal forms on them — RussellA

When you say, we impose space and temporal forms on the sensory experiences, it does imply we can also choose not to impose as well. So what happens if we choose not to impose? How do we decide to impose or not to impose?
I am going to tackle your points one by one taking time (no rush) in order to avoid any confusions.

experiments on time and space — Corvus

An experiment on time. I’ll bet it’s actually an experiment on something relative to time.

An experiment on time. I’ll bet it’s actually an experiment on something relative to time. — Mww

Space as well. It is called "Spatio-Temporal Transcendental Deduction".

Reference? Link?

Reference? Link? — Mww

Sorry cannot locate the link or ref. for now. Will look for it and update when time allows. :)

An example of a Transcendental argument is used by Kant in his refutation of idealism. Idealists believe that things have no existence independently of the mind. — RussellA

Wasn't Kant refuting the rationalists rather than idealism? If it were idealists, who were they?

His Transcendental argument does not prove that things exist independently of the mind, only that the concept that things exist independently of the mind is legitimate. — RussellA

What is the proof of the legitimacy of the concept that things exist independently of the mind?

Kant argues that:
1) since idealists acknowledge that we have an inner mental life, and
2) an inner life of self-awareness is bound up with the concepts of objects which are not inner, and which interact causally,
3) then we must have legitimate experience of outer objects which interact causally. — RussellA

Any relevant quotes for this argument from CPR?

Any popular media based information will be flatly rejected as propaganda in all philosophical discussions unless proved and verified otherwise — Corvus

Yes, every source is open to doubt, even the SEP, which is the premier reference work in philosophy.

We know it is the premier work in philosophy because the Stanford Department of Philosophy says so. They write: The Stanford Encyclopedia of Philosophy (SEP) is the premier reference work in philosophy, and covers an enormous range of philosophical topics through in-depth entries.
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When you say, we impose space and temporal forms on the sensory experiences, it does imply we can also choose not to impose as well. — Corvus

No, because this imposition is a priori, and as priori is beyond choice. In the same way that when I see the wavelength of 700nm I have no choice as to what colour I perceive .
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Wasn't Kant refuting the rationalists rather than idealism? If it were idealists, who were they? — Corvus

As the Wikipedia article on Transcendental arguments concludes: He has not established that outer objects exist, but only that the concept of them is legitimate, contrary to idealism

From the Britannica article on Rationalism: Rationalism, in Western philosophy, the view that regards reason as the chief source and test of knowledge.

From Routledge Encyclopedia of Philosophy:Idealism is now usually understood in philosophy as the view that mind is the most basic reality and that the physical world exists only as an appearance to or expression of mind, or as somehow mental in its inner essence.

In B275, Kant mentions Berkeley as an example of a Dogmatic Idealist, someone who declares the existence of objects outside us to be either false or impossible

Kant is refuting Idealism as a belief rather than Rationalism as a method .
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What is the proof of the legitimacy of the concept that things exist independently of the mind? — Corvus

Speaking as an Indirect Realist, none. I believe that things exist independently of the mind, and can come up with reasons to justify my belief, but cannot prove it. Such is the nature of Indirect Realism.

This is a question for the Direct Realist, who does believe that they directly perceive things that exist independently of the mind.
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Any relevant quotes for this argument from CPR? — Corvus

In B275 is the section on The Refutation of Idealism

He includes the Theorem: The mere, but empirically determined, consciousness of my own existence proves the existence of objects in space outside me.

In B276 is the section Proof

I am conscious of my existence as determined in time. All time-determination presupposes something persistent in perception. This persistent thing, however, cannot be something in me, since my own existence in time can first be determined only through this persistent thing. Thus the perception of this persistent thing is possible only through a thing outside me and not through the mere representation of a thing outside me. Consequently, the determination of my existence in time is possible only by means of the existence of actual things that I perceive outside myself. Now consciousness in time is necessarily combined with the consciousness of the possibility of this time-determination: Therefore it is also necessarily combined with the existence of the things outside me, as the condition of time-determination; i.e., the consciousness of my own existence is at the same time an immediate consciousness of the existence of other things outside me.

In other words:

1) I am conscious of my existence in time
2) Therefore I am conscious of something persisting in time
3) But this something that persists in time cannot be inside me, as this something cannot be conscious of itself
4) Therefore as this something that persists cannot be a representation inside me, this something that persists must be outside me.
5) Concluding that there must be something outside me, refuting Idealism which believes there is nothing outside me.

No, because this imposition is a priori, and as priori is beyond choice. In the same way that when I see the wavelength of 700nm I have no choice as to what colour I perceive . — RussellA

A priori means that it is universally true under all circumstances. If you say that you see the WL700nm, and you perceive the colour red. You claim that you have no choice but perceive the colour under A priori condition.

But if that is the case, how do you explain that some other people perceive the colour differently, or no colour at all (in the case of colour blind people)? Surely that proves the point that colour perception is not A priori?

Speaking as an Indirect Realist, none. I believe that things exist independently of the mind, and can come up with reasons to justify my belief, but cannot prove it. Such is the nature of Indirect Realism. — RussellA

How / Why do you justify your belief in something that you cannot prove it exists?

No, because this imposition is a priori, and as priori is beyond choice. In the same way that when I see the wavelength of 700nm I have no choice as to what colour I perceive . — RussellA

This sounds a bit vague and needing some more discussion. OK, you perceive the colour by seeing the WL700nm, you claim. If that is the case, what is the relation between the colour you perceive (red), and the WL700nm? Are they same in nature, substance and composition? The WL700nm itself is not the colour you perceive itself, is it?

After seeing the red colour, you close your eyes, and you can visualise the colour you have just seen in your mind. It appears in your mind as red colour. Then what is that red colour? Is it the WL700nm? or something else?

In other words:

1) I am conscious of my existence in time
2) Therefore I am conscious of something persisting in time — RussellA

How does he know for certain what he is conscious of is not an illusion?

3) But this something that persists in time cannot be inside me, as this something cannot be conscious of itself — RussellA

Does this mean, if something was conscious of itself, then it could be inside him? :chin:

A priori means that it is universally true under all circumstances. — Corvus

The IEP article on A Priori and A Posteriori writes: An a priori concept is one that can be acquired independently of experience, which may – but need not – involve its being innate, while the acquisition of an a posteriori concept requires experience.

A Priori does not mean universally true for all people at all times. A priori means in a sense innate within a particular person. My private subjective experience of colour when seeing a wavelength of 700nm is innate to me.

How can you know that when you are look at a wavelength of 700nm, your private subjective experience of colour is the same as mine?
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How / Why do you justify your belief in something that you cannot prove it exists? — Corvus

I cannot prove that electrons exist, yet I believe they exist. I justify my belief from the numerous scientific articles that I have read that say that electrons do exist.

Do you believe that the Andromeda Galaxy exists? Can you prove that it exists?
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what is the relation between the colour you perceive (red), and the WL700nm? — Corvus

Totally mysterious. What do you think the relationship is?
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How does he know for certain what he is conscious of is not an illusion? — Corvus

Isn't this the argument against Direct Realism, in that if Direct Realism was true, the external world would be exactly as we perceive it. However, in the case of illusions, there is an obvious difference between our perception and reality. For example, when a pencil is placed in a glass of water, it can look crooked. But it isn't really crooked.

Kant was definitely not a Direct Realist.

How does the Direct Realist know when looking at something in the world, such as a tree, that what they think they are looking at is just an illusion?
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Does this mean, if something was conscious of itself, then it could be inside him? — Corvus

Not everyone agrees with Kant's Transcendental Argument.

If I am conscious of the passing of time, then I must be conscious of two different moments in time. But how is this possible if I only exist at one moment in time?

The IEP article on A Priori and A Posteriori writes: An a priori concept is one that can be acquired independently of experience, which may – but need not – involve its being innate, while the acquisition of an a posteriori concept requires experience.

A Priori does not mean universally true for all people at all times. A priori means in a sense innate within a particular person. My private subjective experience of colour when seeing a wavelength of 700nm is innate to me. — RussellA

Not sure what the IEP article was about, but it doesn't sound right. If A priori is just innate to you, and all different from person to person, then what is the point of A priori? Would it not better just as well call it as Relative concept rather than A priori? There must be some universality and necessity in truth on A priori, and that was what Kant was after in CPR.

How can you know that when you are look at a wavelength of 700nm, your private subjective experience of colour is the same as mine? — RussellA

I can't know what your perception of WL700nm would be like, and that was the point. Your claim on "A priori imposition of colour Red for the perceived WL700nm" doesn't sound valid, does it? If it were A priori imposition as claimed, then we must all have the same colour of Red in the visual perception. But we don't. Therefore, it cannot be A priori imposition.

How / Why do you justify your belief in something that you cannot prove it exists?
— Corvus

I cannot prove that electrons exist, yet I believe they exist. I justify my belief from the numerous scientific articles that I have read that say that electrons do exist.

Do you believe that the Andromeda Galaxy exists? Can you prove that it exists? — RussellA

Those are the blind beliefs on the existence that have not been justified. For any beliefs if they were to be qualified as knowledge, then they need empirical or logical justifications with evidences.
Your beliefs on the things that cannot be verified or justified are groundless beliefs.

I know the Andromeda Galaxy exists, but I don't believe it exists. If I believed in its existence without justification or verification, then I would have a groundless belief on it too, and I don't want that.

I have knowledge of its existence which is from heard through the grapevine in nature, which is not a solid justified ground.

More to follow ...

How does he know for certain what he is conscious of is not an illusion?
— Corvus

Isn't this the argument against Direct Realism, in that if Direct Realism was true, the external world would be exactly as we perceive it. However, in the case of illusions, there is an obvious difference between our perception and reality. For example, when a pencil is placed in a glass of water, it can look crooked. But it isn't really crooked. — RussellA

Yes, but my question was how do you know it is real or illusion? How can you be sure?
What is the obvious difference between our perception and reality and also illusion?
I should have asked these questions to Kant, but he is not around unfortunately, hence you have been asked, because you decided to quote him.

Kant was definitely not a Direct Realist. — RussellA

Definitely not.

How does the Direct Realist know when looking at something in the world, such as a tree, that what they think they are looking at is just an illusion? — RussellA

Not sure. I am not a DRist either. Maybe they perceive illusions as real too? Yes, real illusions? :)

I haven't been following this thread, but the CPR is a great read and I would highly recommend reading it. Kant's mode of analysis is brutally frigid and to-the-point, which I appreciate; and most of the work, if not all of it, is very thoroughly thought out.

Schopenhauer, who builds his own metaphysics from Kant's, is also a great read. On top of reading CPR, I would suggest reading Schopenhauer's critiques of it found in the appendix of the WWR: S's critiques can also help one understand what K is getting at.

For me, I can say that I owe to Kant a couple things:

1. He awoke me from my direct realist dogmatic slumber;
2. He introduced me to a priori knowledge;
3. He made me think way to deeply about what reasons I really have for thinking I have any sort of knowledge of the world as it is in-itself, lol; and
4. His metaphysics on time and space I largely endorse.

A Priori does not mean universally true for all people at all times. — RussellA

I don't think your depiction of a priori as subjective is correct. A priori facts don't need to be validated against experience, they are known to be so by dint of logic alone.

If A priori is just innate to you, and all different from person to person, then what is the point of A priori? — Corvus

:up:

I cannot prove that electrons exist, yet I believe they exist. I justify my belief from the numerous scientific articles that I have read that say that electrons do exist. — RussellA

The problem with that view is that the manner in which electrons can be said to exist is not at all straightforward. As is well-known, electrons and other sub-atomic particles are said to manifest as waves in some contexts and as particles in others, depending on the nature of the experiment (although this is not the thread for that, there's some discussion of it in this thread.)

We have to get our head around the role of the mind-brain in constructing/creating what we perceive as reality. Kant and Schopenhauer both understood that, but it's rather a difficult thing to grasp. It requires something like a gestalt shift in perspective, more than just discursive reasoning.

Schopenhauer, who builds his own metaphysics from Kant's, is also a great read. — Bob Ross

Indeed. Of all the great philosophers, he is the most clearly-spoken and incisive.

Indeed. Of all the great philosophers, he is the most clearly-spoken and incisive. — Wayfarer

Plato, Aristotle, Hume, Kant, Hegel and Schopenhauer are my favourite philosophers. But I see Kant as the most important philosopher of all time. Any topic we pick up this day, it is very likely that it had been already discussed and investigated by those philosophers already.

A quick note about ‘illusion’.

If everything perceived is an ‘illusion’ then the term has no meaning. Either there are perceptions that are illusions and perceptions that are not illusions or there are no perceptions.

Language is useful if adhered to.

If A priori is just innate to you, and all different from person to person, then what is the point of A priori? Would it not better just as well call it as Relative concept rather than A priori? There must be some universality and necessity in truth on A priori, and that was what Kant was after in CPR.........................I can't know what your perception of WL700nm would be like, and that was the point. — Corvus

The point of the a priori is that it distinguishes two very different approaches to the relationship between the mind and the world.

It distinguishes between Innatism, the philosophical belief that one is born with certain ideas and knowledge, and Locke's idea that the mind at birth is a blank sheet, a tabula rasa, devoid of all ideas or knowledge, where all our ideas and knowledge arrive from experience.

For Kant, the mind has a role in constructing what we perceive as reality:
A239 - We can only cognize objects that we can, in principle, intuit. Consequently, we can only cognize objects in space and time, appearances. We cannot cognize things in themselves.

I agree that there is the question as to the universality and necessity of such a priori ideas and knowledge :
Introduction - Kant also sought to defend against empiricists its underlying claim of the possibility of universal and necessary knowledge - what Kant called a priori knowledge, knowledge originating independently of experience, because no knowledge derived from any particular experience, or a posteriori knowledge, could justify a claim to universal and necessary validity.

As Hume showed, no a posteriori knowledge can justify a universal and necessary validity, in that a scientist can draw a conclusion from 1,000 measurements, yet that conclusion may be negated by the 1,001st measurement.

It is true that for me, my a priori ideas and knowledge, because they are a priori, ensure a universality and necessity to what I cognize. However, humans do not exist as a hive mind but as separate individuals.

My a priori ideas and knowledge ensure a universality and necessity to what I cognize, and your a priori ideas and knowledge ensure a universality and necessity to what you cognize. The question is, is there any reason to believe that your a priori ideas and knowledge are the same as my a priori ideas and knowledge. If not, even though there is a universality and necessity to our individual ideas and knowledge, our separate ideas and knowledge don't necessarily share a common universality and necessity.
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I know the Andromeda Galaxy exists, but I don't believe it exists. — Corvus

I think that this should be the other way round: "I believe the Andromeda Galaxy exists, but I don't know it exists"

The SEP article on The Analysis of Knowledge discusses knowledge as justified true belief. First one has a belief, and then one tries to justify this belief, and if one's belief is true, then one has knowledge

IE, belief comes before knowledge.
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Yes, but my question was how do you know it is real or illusion? — Corvus

The Merriam Webster Dictionary includes the meaning of "illusion" as
1a1 - a misleading image presented to the vision
1a2 - something that deceives or misleads intellectually
1b1 - perception of something objectively existing in such a way as to cause misinterpretation of its actual nature

If I perceive a tree, how do I know there is a real tree in the world or the tree only exists in my mind.

The Direct Realist would say that they perceive a tree, and the Indirect Realist would say that they perceive a representation of a tree.

For the Indirect Realist, if "illusion" means 1a2 or 1b1, then the tree is an illusion as the viewer is being misled in thinking that what they perceive of necessity actually exists in the world. If "illusion" means 1a1, then the tree is not an illusion, as the viewer is not being misled in thinking that their perception doesn't exist.

I don't think your depiction of a priori as subjective is correct — Wayfarer

I agree that my innate ability to see the colour red when looking at a wavelength of 700nm is not a subjective ability, although my seeing the colour red is a subjective experience .
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The problem with that view is that the manner in which electrons can be said to exist is not at all straightforward.........................We have to get our head around the role of the mind-brain in constructing/creating what we perceive as reality. — Wayfarer

Do electrons really exist?

It depends what you mean by "exist". The Merriam Webster Dictionary includes "exist" as "to have real being whether material or spiritual".

It depends what you mean by "real". The Merriam Webster Dictionary includes "real" as "having objective independent existence".

From my belief in Neutral Monism, I could ask the same question about apples: "Do apples really exist?"

My answer would be that yes, "apples" and "electrons" do exist, and they exist as concepts in the mind.

My answer would also be that "apples" and "electrons" are real in that they have an objective independent existence within language.

The very point of a priori mental machinations never was the mind, re: human intellectual system, in relation to the world, but the relation of the human intellectual system to itself. Such system does not come pre-equipped with principles but with the faculty of reason, experience the condition of the development of them by means of that faculty. How else to escape constant conjunction, then to cognize the very possibility of exceptions to it?

“…. The question now is as to a criterion, by which we may securely distinguish a pure from an empirical cognition. Experience no doubt teaches us that this or that object is constituted in such and such a manner, but not that it could not possibly exist otherwise. Now, in the first place, if we have a proposition which contains the idea of necessity in its very conception, it is priori. If, moreover, it is not derived from any other proposition, unless from one equally involving the idea of necessity, it is absolutely priori. Secondly, an empirical judgement never exhibits strict and absolute, but only assumed and comparative universality (by induction); therefore, the most we can say is—so far as we have hitherto observed, there is no exception to this or that rule. If, on the other hand, a judgement carries with it strict and absolute universality, that is, admits of no possible exception, it is not derived from experience, but is valid absolutely à priori. Empirical universality is, therefore, only an arbitrary extension of validity, from that which may be predicated of a proposition valid in most cases, to that which is asserted of a proposition which holds good in all (…). When, on the contrary, strict universality characterizes a judgement, it necessarily indicates another peculiar source of knowledge, namely, a faculty of cognition à priori. Necessity and strict universality, therefore, are infallible tests for distinguishing pure from empirical knowledge, and are inseparably connected with each other.

“…. Besides, without seeking for such examples of principles existing à priori in cognition, we might easily show that such principles are the indispensable basis of the possibility of experience itself, and consequently prove their existence à priori. For whence could our experience itself acquire certainty, if all the rules on which it depends were themselves empirical, and consequently fortuitous? No one, therefore, can admit the validity of the use of such rules as first principles. But, for the present, we may content ourselves with having established the fact, that we do possess and exercise a faculty of pure à priori cognition; and, secondly, with having pointed out the proper tests of such cognition, namely, universality and necessity.…”

“…. Of far more importance than all that has been above said, is the consideration that certain of our cognitions rise completely above the sphere of all possible experience, and by means of conceptions, to which there exists in the whole extent of experience no corresponding object, seem to extend the range of our judgements beyond its bounds. And just in this transcendental or supersensible sphere, where experience affords us neither instruction nor guidance, lie the investigations of reason, which, on account of their importance, we consider far preferable to, and as having a far more elevated aim than, all that the understanding can achieve within the sphere of sensuous phenomena.….”

My answer would be that yes, "apples" and "electrons" do exist, and they exist as concepts in the mind.

My answer would also be that "apples" and "electrons" are real in that they have an objective independent existence within language. — RussellA

But that is an oxymoron (although I am totally sympathetic to your struggles in these deep and difficult matters).

It is a matter of contention whether the paradoxical attributes of the objects of quantum physics can be said to obtain to the objects of sensory perception. Werner Heisenberg, who aside from being one of the architects of quantum theory, also wrote on its philosophical implications, said that electrons 'do not exist in the same way that flowers or stones do' (in 'The Debate between Plato and Democritus').

Some physicists would prefer to come back to the idea of an objective real world whose smallest parts exist objectively in the same sense as stones or trees exist independently of whether we observe them. That, however, is impossible. —WERNER HEISENBERG — Kripal, Jeffrey J.. The Flip: Who You Really Are and Why It Matters (p. 89). Penguin Books Ltd. Kindle Edition.

Second, with respect to the reality of the proverbial apple, I too am an empirical realist - there really are apples - but I also recognise the sense in which they exist for a subject. Another kind of being might not see them at all, or might see them in a completely different way. It doesn't mean that they don't exist, but that they don't have inherent existence - they are absent what Buddhist philosophy describes as 'own-being'.

But that is an oxymoron — Wayfarer

If the concept of "apple" didn't exist, how could we be talking about the concept of "apple"?
If the word "apple" wasn't real, how could we be writing about the word "apple"?
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Werner Heisenberg, who aside from being one of the architects of quantum theory, also wrote on its philosophical implications, said that electrons 'do not exist in the same way that flowers or stones do' — Wayfarer

Consider the mind and a mind-independent world.

As regards a mind-independent world, as flowers and stones are sets of elementary particles, flowers and stones must exist in the same way that elementary particles exist.

As regards the mind, as flowers, stones and elementary particles are concepts in the mind, elementary particles exist in the same way that flowers and stones do .

It is true that elementary particles, flowers and stones exist differently in the mind to how they exist in a mind-independent world.

As regards a mind-independent world, Plato's Forms are aspatial and atemporal, which is not the case for elementary particles.
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I too am an empirical realist - there really are apples - but I also recognise the sense in which they exist for a subject. Another kind of being might not see them at all, or might see them in a completely different way. It doesn't mean that they don't exist, but that they don't have inherent existence — Wayfarer

Yes, for the Empirical Realist, the apple that is perceived is a mere representation, not something that is mind-independent.

When you say the apple exists, but doesn't have inherent existence, what do you mean?

“…. In truth, it is not images of objects, but schemata, which lie at the foundation of our pure sensuous conceptions. No image could ever be adequate to our conception of a triangle in general. For the generalness of the conception it never could attain to, as this includes under itself all triangles, whether right-angled, acute-angled, etc., whilst the image would always be limited to a single part of this sphere. The schema of the triangle can exist nowhere else than in thought, and it indicates a rule of the synthesis of the imagination in regard to pure figures in space. Still less is an object of experience, or an image of the object, ever to the empirical conception. On the contrary, the conception always relates immediately to the schema of the imagination, as a rule for the determination of our intuition, in conformity with a certain general conception. The conception of a dog indicates a rule, according to which my imagination can delineate the figure of a four-footed animal in general, without being limited to any particular individual form which experience presents to me, or indeed to any possible image that I can represent to myself in concreto.

This schematism of our understanding in regard to phenomena and their mere form, is an art, hidden in the depths of the human soul, whose true modes of action we shall only with difficulty discover and unveil. Thus much only can we say: “The image is a product of the empirical faculty of the productive imagination—the schema of sensuous conceptions (of figures in space, for example) is a product, and, as it were, a monogram of the pure imagination à priori, whereby and according to which images first become possible, which, however, can be connected with the conception only mediately by means of the schema which they indicate, and are in themselves never fully adequate to it.” On the other hand, the schema of a pure conception of the understanding is something that cannot be reduced into any image—it is nothing else than the pure synthesis expressed by the category, conformably, to a rule of unity according to conceptions. It is a transcendental product of the imagination, a product which concerns the determination of the internal sense, according to conditions of its form (time) in respect to all representations, in so far as these representations must be conjoined à priori in one conception, conformably to the unity of apperception.

Without entering upon a dry and tedious analysis of the essential requisites of transcendental schemata of the pure conceptions of the understanding, we shall rather proceed at once to give an explanation of them according to the order of the categories, and in connection therewith. For the external sense the pure image of all quantities (quantorum) is space; the pure image of all objects of sense in general, is time. But the pure schema of quantity, a conception of the understanding, is number, a representation which comprehends the successive addition of one to one (homogeneous quantities). Thus, number is nothing else than the unity of the synthesis of the manifold in a homogeneous intuition, by means of my generating time itself in my apprehension of the intuition….”
———-

Number does not exist in the mind as appearance or phenomena, unless it is created as such in a non-fallacious post hoc ergo propter hoc cognition following from a transcendental synthetic unity.

Every human, or every species with this particular intellectual method, including mathematicians and logicians, busboys and cab drivers, is a transcendental idealist and an empirical realist, or, more precisely, a dualist. A dualist fundamentally understood as that which has the ability to comprehend Nature under conditions which are not contained in it.

The point of the a priori is that it distinguishes two very different approaches to the relationship between the mind and the world.

It distinguishes between Innatism, the philosophical belief that one is born with certain ideas and knowledge, and Locke's idea that the mind at birth is a blank sheet, a tabula rasa, devoid of all ideas or knowledge, where all our ideas and knowledge arrive from experience. — RussellA

When you say "Innatism", it denotes psychological or biological nature rather than epistemic, conceptual nature, and it has nothing to do what Kant was meaning for A priori. A priori knowledge is for universally and necessarily true knowledge, and there is no room for difference in the truth value.

For example 2+2=4 is A priori knowledge, which is universally and necessarily true in the whole universe. There is no way, that it is 4.5 for you, and 4.1 for me, and 3.9 for a bloke in some other remote place on the earth.

Therefore you read about A priori knowledge or concept, but never A priori sensation or perception (absurd expression).

I know the Andromeda Galaxy exists, but I don't believe it exists.
— Corvus

I think that this should be the other way round: "I believe the Andromeda Galaxy exists, but I don't know it exists"

The SEP article on The Analysis of Knowledge discusses knowledge as justified true belief. First one has a belief, and then one tries to justify this belief, and if one's belief is true, then one has knowledge

IE, belief comes before knowledge. — RussellA

Justified true belief has stronger ground than a knowledge via heard through the grapevine. I really don't believe the electrons, atoms and Andromeda galaxies exist, because I have never seen them, or been there. Without me personally justifying and verifying the facts, there is no ground for me in believing in them.

But I know they exist, because I read about them. Just because I know something doesn't mean that I must believe in it too.

Even if the contents were from SEP, if it sounds irrational and not making sense, you should think, reflect on it, and reject them, and be able to tell the difference between truth and false. That is what philosophy is all about. Thinking with your own reasoning is what matters most, rather than just reading the information from the well known institutions, and blindly accepting them.

More later~

When you say "Innatism", it denotes psychological or biological nature rather than epistemic, conceptual nature, and it has nothing to do what Kant was meaning for A priori. — Corvus

For Kant there is a priori pure intuition of space and time and the a priori pure concepts of the understanding (the Categories)

These are necessary for the possibility of experience, and are priori to experience. They don't come from the mind but are part of the mind.

My question is, where did these pure intuitions and pure concepts come from?

From a perspective of today, I can explain them using the concept of Innatism, in that we were born with them as part of the structure of the brain as a consequence of 3.5 billion years of evolution.

If not from Innatism, where do you think our pure intuitions and pure concepts came from?
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For example 2+2=4 is A priori knowledge, which is universally and necessarily true in the whole universe. — Corvus

For Kant there is a priori pure intuition of space and time and the a priori pure concepts of the understanding (the Categories).

For example, the Categories include quantity, quality, relation and modality, and quantity includes such things as all, both, most and some.

This allows us when looking at a set of objects to make judgements such as "all the objects green", "both objects are blue", "most of the objects are orange" and "some of the objects are purple".

Then, given ten objects of which six are orange, some of these statements will be true and some will be false. For example, the statement "most of the objects are orange" will be true.

As no situation can be imagined whereby given ten objects of which six are orange, the statement "most of the objects are orange" will not be true, meaning that it is universally and necessarily true.

However, the Categories don't apply to unknown Things-in-Themselves, but only to known Appearances.

As this is the case, then what does universal and necessary refer to. They cannot refer to the world of Things-in-Themselves, as these are unknowable, but can only refer to the world of Appearance, as only this is knowable, and the world of Appearance only exists in the mind of the perceiver.

Therefore, it is true that a priori knowledge is universally and necessarily true in the whole universe, but this universe only exists in the mind of the perceiver, not in any world that exists outside the mind of the perceiver.
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Justified true belief has stronger ground than a knowledge via heard through the grapevine. I really don't believe the electrons, atoms and Andromeda galaxies exist, because I have never seen them, or been there. But I know they exist, because I read about them. — Corvus

Knowledge is justified true belief, so knowledge has a stronger ground than belief.

If from the grapevine one hears the belief that atoms exist, and the grapevine justifies the claim, and in fact atoms do exist, then, and only then, is this knowledge.

If not from Innatism, where do you think our pure intuitions and pure concepts came from? — RussellA

Kant was saying that pure intuitions and concepts are the the properties of our minds which work with pure reason in CPR. He is not interested in where they came from as if, they have walked into a pub, or inherited down into your mind by your ancestors. No no. :)

but this universe only exists in the mind of the perceiver, not in any world that exists outside the mind of the perceiver. — RussellA

That sounds like extreme idealism. We are talking about the universally and necessarily true knowledge, and it exists. Again it is nothing to do with the physical universe. Knowledge exists in our understanding. Universally doesn't mean the physical universe. It means "under all conditions".

They cannot refer to the world of Things-in-Themselves, as these are unknowable, — RussellA

You just committed a self-contradiction here. You shouldn't even be able to write about it, if above were true.

Knowledge is justified true belief, so knowledge has a stronger ground than belief.

If from the grapevine one hears the belief that atoms exist, and the grapevine justifies the claim, and in fact atoms do exist, then, and only then, is this knowledge. — RussellA

I have demonstrated how even the most [t]rusted and accepted official definitions could be false, but you have gone back to the false official definition ignoring the real life demonstration and evidence.

Kant was saying that pure intuitions and concepts are the the properties of our minds which work with pure reason in CPR. He is not interested in where they came from — Corvus

Possibly, but his philosophy isn't complete without asking where these a priori pure intuitions and a priori Categories came from.
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For example 2+2=4 is A priori knowledge, which is universally and necessarily true in the whole universe.----------------That sounds like extreme idealism. We are talking about the universally and necessarily true knowledge, and it exists. Again it is nothing to do with the physical universe. Knowledge exists in our understanding. Universally doesn't mean the physical universe. It means "under all conditions". — Corvus

When you refer to "universe" do you mean a universe within the mind or a universe external to the mind?
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You just committed a self-contradiction here. You shouldn't even be able to write about it, if above were true. — Corvus

From the Principle of Sufficient Reason, an appearance must have a cause, which may well be unknown. This unknown cause can be called "x", or even "Thing-in-Itself".
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But I know they exist, because I read about them. Just because I know something doesn't mean that I must believe in it too.-----------------I have demonstrated how the official definitions could be false, but you have gone back to the false official definition ignoring the real life demonstration and evidence. — Corvus

How can you know atoms exist, yet not believe in their existence?