1. I don't believe we have souls.

2. You are conflating the adjective 'human' insofar as it relates to something being a part of a human with the noun 'human' insofar as it relates to something being a human. E.g., my human skill cell (which is a redundant way to put it btw) is not a human.

No, we don't know what it is. We don't know if its an object, if its physical, if it many things, or something beyond our imagination or comprehension. All we know is there is some 'thing', and 'thing' in only the loosest and most abstract sense. All of those words you used to describe it are words formed from physical sensations, or interpretations.

Agreed, to some extent. By physical, I do not mean material: I mean mind-independent.

Even if we could not even know that it is mind-independently existing; the thing as it is in-itself is not purely logical (in that case): we are talking about some ‘thing’ which exists—we are talking in concreto.

No, our brain does not have to know how to intuit and cognize objects in space independently of any experience it has. It has the capacity to do so.
Just like our minds have the capacity to take light and concentrate on aspects of them. We have the ability to discretely experience, but that ability is not knowledge.

Correct me here @Mww. I would say that my example was bad insofar as the intuition aspect of representation in space is non-cognitive (so there is no knowledge in that regard), but that our faculty of judgment, understanding, and cognition must formulate justified, true, beliefs in relation to the a priori principles and conceptions in order to actually represent the objects in space, according to spatial-mathematical relations.

Think of it like this. A newborn has the capacity to be able to walk one day. Does it know how to do so apart from experience? No

A newborn does not have the capacity to walk: the biological structures required are not there (e.g., muscle, bone density, etc.). Now, once it has that capacity, of course, I agree it still has to learn how to walk; but this is disanalogous.

When you speak of knowledge without experience, you must speak of a newborn

Everything described in the transcendental analytic applies to newborns. E.g., newborns know how to cognize objects in space and time, to cognize in accordance with logic, to cognize in according with math, etc.

Obviously, the newborn doesn’t have the self-reflective knowledge about it (that would be needed to solve a math problem at school).

This is the part I disagree with. A child does not know how to construct things in space. I

This is an equivocation. We are talking about the child qua its representative faculties; not its self-reflective reason.

Skimming over a couple of the other replies here, I think its the term 'thing' that's throwing people. We can rephrase a 'thing in itself' to 'the unknowable reality' Its not a 'thing' like an 'object'. Its just a logical conception that we always interpret reality, and we cannot know reality as it is uninterpreted. That's all.

Edit: I just realized there's other simple ways to explain it. The brain in the vat. An evil demon. The matrix. All of these are 'things in themselves' that we could never know. Its just the same type of argument.

True.

I didn't say that the living human being was a person during the entirety of gestation; and I've already noted that I ground rights in the nature of a being such that if their nature sets them out as a person, then they deserve rights even if they aren't currently a person.

A sperm and egg are alive: no one disputes that. The fact is, also, that a human being begins to exist upon conception of those two. A sperm is alive, but is not a human; an egg is alive but is not a human, but a fertilized egg is a human.

I am getting closer to understanding what you are saying, but I am still not quite there.

Here’s the core of our issue:

By definition the real is that which is contained in reality, and by definition reality is that of which the susceptibility to sensation is given.

I understand better now why you deny the existence of things-in-themselves: you are operating under a false understanding of what reality is. Reality is not itself the totality of that which is, at least in principle, capable of being sensed—that’s what’s called our limits of sensing reality.

Do you really believe that all objects in reality are possible objects of sense for humans? I find that obviously and patently false. There’s absolutely nothing about reality that entails that there isn’t an object which we are incapable of sensing.

If you take that reality is the totality of existence, on the contrary, then you find that things-in-themselves, as properly understood, are the things which comprise that totality.

but it's based on the assumption that a mind is not a continuous entity but a series of unrelated instances

I am not a bundle theorist; and nothing I said entails that. The mind persists as long as its underlying physical constitution is preserved through processes and storage; but this is not the same as claiming that a malfunctioning brain, which may still be a means of preserving a mind, is currently producing a person.

Personhood, as I take it, is a property that a thing has when it currently has a rational will; and this is not found in unconscious humans.

Uh, what is absurd about that? Why would dead human beings have rights?

Imagine there’s a person who just died and all their family members or loved ones are dead. A stranger wants to have sex with their corpse: if that dead person has no rights, being dead, then there is nothing, per se, immoral about having sex with their corpse. Are you willing to bite that bullet?

A response one could give is that some actions are immoral and yet don’t violate a right of someone else—e.g., torturing a pig. They would then point out that, similarly, the dead person has no rights but it would still be immoral to have sex with their corpse.

To that, I respond that it is disanalogous; for the actions which are immoral but don’t directly violate a right (of a person) can be morally permissible per accidens (e.g., having to torture a pig if it were to prevent a major societal catastrophe), whereas it is always wrong to have sex with a dead person's corpse (no differently than it is always wrong to kill an innocent person). Persons, given their nature qua rationality, marks them out as absolute objects of respect.

This is fine if we're talking about subjects where there's no disconnect between what the teleology says it's natural and what individuals usually want

That, and everything you commented, is completely anti-thetical to everything I said. When a person says that their arm is not working properly, they usually are saying it in the Aristotelian sense and not this post-humean sense that you described. Viz., they are saying something is actually wrong with their arm, and not that it is wrong hypothetically relative to their subjective tastes.

On the subject of abortion, that brings us back to the familiar question: does a fetus have a presumed interest to become a person?

Your problem is that you are thinking about this like a Humean. This question makes no sense for an Aristotelian.

But what do the biologists mean when they say life?

They mean that a new member of the human species has been created and is alive.

(2) For all series, having no 1st term implies having no nth term.

This premise is patently false, and is the denial, implicitly, that the concept of infinity is coherent. Viz., you are getting this argument to work by denying that infinity, in principle, is internally coherent.

Let's take set theory as an example: an infinite set has no first member but has a infinite amount of members such that wherever we start enumerating, n, there is a n+1, n+2, etc. and n-1, n-2, etc.

The fact that an infinite set has no last nor first element, does not mean that it does not have an nth member. There's nothing internally incoherent with the idea of an infinite series of causal events (for example).

By denying "an nth term", you are denying that an infinite set has any members.

"Life begins at conception" is an imprecise short-hand for "a human life begins at conception". Stop picking the low hanging fruits: obviously a sperm is alive and so is my skin cells---we are talking about when a human being is alive.

Yes fair enough, but I would still argue that even an unconscious mind is a mind. The neuron firings of an unconscious person don't turn into a random jumble and then spontaneously reassemble into a mind when that person wakes up. There is continuity.

What you are describing is a capacity to deploy a mind, and not having a mind. Therefore, you must agree that a knocked out human being technically isn’t a person when they are knocked out; and re-gain personhood when they re-gain consciousness.

This is not a minor point: your whole argument relied on personhood grounding rights, not the capacity to acquire personhood (because they have a fully developed brain). You are starting to morph into my view: the nature of that being sets them out as a person, because they can and will, if everything goes according to the proper biological development, develop personhood.

Also, if you go the capacity route; then you end up with the absurdity that dead human beings have no rights...just food for thought.

Ok, then what part of that biology are you calling nature

I am talking about how a healthy member of a species is supposed to develop and become. People think of “teleoglogy” as a dirty word these days, or a vacuous concept, but we use it implicitly all the time in the medical industry.

When you go into the doctor’s office and complain about your hand not acting properly, or when a child is born without an arm and you take pity on them, you are talking necessarily in teleological terms: your hand, e.g., was supposed to, according to what a healthy human hand normally does, behave such-and-such instead of so-and-so.

You have a nature which is set out by your biology which is set out by the species which you are a member of. Zebras are supposed to have stripes: a zebra which doesn’t have stripes is an abnormality—a defect.

That's interpretation, not fact.

There’s a huge consensus in biology that life begins at conception; so it’s, quite frankly, not worth my time to argue about it. Here’s a good article on it: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3211703 .

Experience is not sensations. Sensations are the raw data which is intuited, judged, and cognized into a representation which, as a result, is your experience. E.g., a ball excites your senses by "impact" of whatever it is in-itself exciting your sensibility, and then sensations of that excitation are passed to your brain to interpret...there's nothing contradictory going on here.

The thing in itself is the thing considered by reason alone. As the referenced quote says.

I guess I didn’t follow it: can you elaborate more on this?

I am thinking that we use reason to determine that there must be a thing-in-itself which is the ground for our experience of some thing; and that this is a claim in concreto about the thing as opposed to in abstracta. I think, now, you may be saying vice-versa.

Yes, and no. Limits, but not as relates to rationalism vs empiricism.

That was the whole underlying context of the CPR. Kant was addressing philosophers like Descartes, Wolf, etc. and Locke, Hume, etc. with respect to their long standing disputes about knowledge.

The limitation is proof for the impossibility of an intelligence of our kind ever cognizing the unconditioned.

So, the thing-in-itself to you is not real? The thing as it is unconditioned isn’t real?

There is a living human being that is created upon conception; so that is where it begins as a living being. After birth is not at all when it becomes a human being: that makes no sense.

This is helpful: I am also wondering if this is what @Mww is talking about. I am viewing the thing-in-itself as the thing as it really is. What is your interpretation, then, of the ding an sich?

No they are not. That's not how biology works: they are separate living beings of which one is dependent on the other.

The thing as a whole excites such that we perceive, but it isn’t the whole thing we intuit from that perception. The thing as a whole is not the same a a thing in itself.

I am still not understanding what you are claiming the thing-in-itself is: I am saying it is the thing which excites our senses. Can you put in simple terms what you think it is?

What do you think the thing-in-itself actually is, what concept is being represented by those words?

It represents an object in reality as it is in-itself—i.e., qua itself—i.e., independent of any experience of it—…

As far as that goes, what do you think the Big Picture is for CPR?

Kant is outlining the limits of reason; especially as it relates to rationalism vs. (british) empiricism.

And why, exactly, is it that the thing-in-itself ends up as one of the necessary limitations proved for this particular, albeit theoretical, method of human cognition and empirical knowledge?

Because something representational requires something which was not representational which grounds it.

And make no mistake: by his own admission, but in modern venencular, Prolegomena is “CPR For Dummies”, so if one wishes to critique the one, he must set aside the other.

Haha. I also read the CPR: I’ll try and pull some quotes sometime this week for you.

Yes, because I am a person.

That’s not how it works...at all. A ball doesn’t know what a ball is.

And? I didn't claim any brain makes a person. Some brains do though.

My point was that just because neurons are firing in a brain, that does not necessitate there is a person.

Personhood is mindhood: it is having a mind, not having a brain that could produce a mind or “house” a mind.

You are conflating a capacity for personhood with personhood.

I did not claim evolution is arbitrary. The concept of "nature" is arbitrary.

Nature is defined by evolutionary biology.

It's a scientific fact that, at conception, two cells fuse to become one, combining their genetic material.

Thereby creating a new life, which thereby begins its continual-development process until death.

??? . I can't tell if you are joking.

This seems silly. An unconscious person isn't brain-dead.

Do you know what personhood is? Just because a brain is firing neurons doesn’t mean that that being, which has that brain, is a person. E.g., a dog is not a person (traditionally).

must instead rely on arbitrary "nature".

Evolution is not arbitrary: that is a myth invented by some evangelical religious people.

Obviously "life" does not begin at conception, since all the cells involved are already alive before they fuse.

It is an undisputed scientific fact that life begins at conception: it is the clear beginning mark of the ever-continual development cycle of an individual human being (until death).

Notice in the text it’s “objects which affect our senses”, not thing-in-themselves. Which is to say things-in-themselves are not that which affects our senses.

But it clearly said it in the Prolegomena! Quite frankly, I am pretty sure it also says it outright in the CRP; but I don’t have time right now to skim through and try to find it—so take that part with a grain of salt.

Then I’d love to know, for you to inform me, what sensation I would receive from a thing-in-itself.

You would receive sensations from your senses of what it sensed of the thing as it were in-itself. I don’t understand how this is controversial. Viz., the ball hits your arm, your neurons fire, intuiting & judging & cognizing & … happen, and then you experience the feeling of getting hit.

You are talking about a thing-in-itself as if it never excites our senses—what then, is the point? That seems like a noumena in that stricter sense of an object which is not a possibly sensed or/and represented by our faculties.

If I receive a sensation in conjunction with the sensory device being impacted, then I should be able to smell, hear, taste, etc., a thing-in-itself. How, then, do I distinguish it from a thing?

Why would that be the case? If the ball hits your arm, you end up experiencing the sensations of the ball that were interpreted by your brain into some sort of perception: the ball as it is in-itself doesn’t get perceived—it gets sensed.

I am not following what you are arguing: are you saying that the thing as it is in-itself does NOT excite our senses such that we perceive something?

Its because it is an abstract. There is nothing to observe.

Hmmm, I disagree with this inference here: an object which is not a possible object of experience is not thereby no object at all. We are not talking about some abstract thing, like a Platonic form, that exists in a supersensible realm nor are we merely talking about a concept in our brains nor minds—we are talking about a real object, a physical object, which simply is not cognizable by us. See what I mean?

The point that I disagree with in apriori is that we can have knowledge without experience.
…
“You cognition must have more than a mere belief to know how to do what it does. E.g., your cognition has a priori knowledge on how to construct objects in space because it clearly does it correctly (insofar as they are represented with extension). The necessary precondition for the possibility of experiencing objects with extension is that your brain knows how to do that.”

Correct, and this aspect of apriori I agree with

I am not following. If you agree that your brain has to know how to intuit and cognize objects in space independently of any possible experience that it has, then you cannot disagree with the idea that some knowledge our brains have are without experience.

Whatever "rational" grounds you might have for believing in naive realism, it is incompatible with physics, biology, neuroscience, and psychology.

I don’t think direct realism is per se incompatible with science: it depends on the view. Personally, I’ve never heard a good argument for direct realism, but I see no inherent incoherence with it conjoined with science.

Also, Leontiskos is absolutely correct to note:

Besides, the belief that science can adjudicate the Kantian question just belies a misunderstanding of the Kantian question, not to mention the science.

Scientific investigations of how we perceive already, to some extent, presuppose the a priori modes by which we intuit and cognize objects, being that we must study the intuited and cognized version of our own representative faculties, and so the Kantian question is still very much alive and puzzling.

All else being equal, we would expect the doctors to do everything they can to rehabilitate them and keep them alive. Circumstances matter, though, as, e.g., the doctors may have to prioritize one sick patient over another; but this is a reflection of limited resources and not a disrespect for human life.

Come on, Bob. Yes, a foetus is not a cyst. A blastocyst is a cyst.

Banno, I know you are a very intelligent person. You cannot possibly think that a blastocyst is a cyst—is the word ‘cyst’ in blastocyst throwing you off?

A zygote is never a cyst: that implies it is a liquid sac that developed abnormally and should be removed. A blastocyst is, even according to your own link, a “hallow ball of cells...[which] implants in the wall of the uterus about 6 days after fertilization”. What you are describing is a stage of the process of development of an alive human being.

A cyst is not a person.

Correct. As I noted in my last response, personhood does not begin at conception; and the best way to ground rights in the nature of the being in question—specifically whether or not its nature sets it out as a person. This is not the same thing as saying that a living being is currently a person.

E.g., a human being that is knocked out on the floor does not have personhood; has the capacity for personhood; and has a nature such that it sets it out as a species which are persons.

Even if we agree that "a human being acquires rights that a person gets because their nature sets them out as being a member of a rational species", the question arrises as to when the cyst becomes a member of that rational species.

The blastocyst is an alive human being: it is a scientific fact that life begins at conception. I am not sure why you would argue the contrary.

A fetus is not a cyst: that is scientifically and blatantly false.

To your point though, and of which I purposefully left out, my view does raise the question of when exactly does a human being acquire rights? If it is personhood, then it clearly doesn't begin [having rights] at conception.

The two basic views is the personhood vs. animalism style arguments, but I think both fail for reasons I will skip over for now. I think that the Aristotelian view works best: a human being acquires rights that a person gets because their nature sets them out as being a member of a rational species. Trying to dissect rights in terms of when a being currently has personhood vs. merely being alive doesn't really work; whereas analyzing the living thing in terms of its substance works great.

Let me give this a crack.

First and foremost, in order for this argument to work, we must agree (at least as a mere stipulation) that the end(s) does (do) not justify the means—viz., I cannot do a bad action for the sake of a good end (e.g., I cannot kill and harvest the organs of an innocent, healthy person to save a sick person’s life).

A person (i.e., a living being with a proper will—i.e., with a mind capable of rational deliberation—or, more generally, a part of a rational species) has certain basic rights; and they have rights, which are not mere privileges, because each person must respect, equally, each other person because they are a person. Two of these rights are the right to bodily autonomy and the right to life.

It is important to note that the right to life is NOT the right to anything required to live, and the right to bodily autonomy is the NOT the right to do anything required to preserve or enforce one’s own will about their own body (i.e., autonomy); exactly because the end does not justify the means. I cannot violate your right to bodily autonomy EVEN IF it would result in the upholding of my own (e.g., forcing you to be my slave and work on a plantation to produce goods that help me maintain my health) because I would be performing a bad action for the sake of something good—which is always wrong.

So here’s why I am pro-life: killing an innocent person is to violate their right to life, and so any action which incorporates killing an innocent person as a means towards a good end, such as upholding the bodily autonomy of a pregnant female, is always wrong. I cannot do something bad to do something good: I must find another way that is permissible, or abstain from interjecting (i.e., let something bad happen).

Does that help?

Sure thing. I don't have time right now to skim back over the whole thing to pull a quote, but the introduction seems to obviously allude to it:

That all our knowledge begins with experience there can be no doubt. For how is it possible that the faculty of cognition should be awakened into exercise otherwise than by means of objects which affect our senses, and partly of themselves produce representations, partly rouse our powers of understanding into activity, to compare to connect, or to separate these, and so to convert the raw material of our sensuous impressions into a knowledge of objects, which is called experience?

--- CPR, p.1

In the Prolegomena, section 32, he also clearly explicates this as well:

In fact, when we (rightly) regard the objects of the senses as mere appearances, we thereby admit that they have a thing in itself as their ground—·namely, the thing of which they are appearances·. We don’t know what this thing is like in itself; all we know is its appearance, i.e. how this unknown something affects our senses. I

If you think about it, it makes no sense to say that the thing-in-itself is not the object which impacted our senses: that's the whole point of the idea of having a representational system based off of sensations.

something has to exist for me to question it. You must demonstrate why that something must be an 'I' which is me---a valid critique from Nietzsche.

I didn't follow that: there's no such thing as a "noumenal a priori concept".

Have you read the CPR? In modern times, the idea that we cannot know anything about the things-in-themselves has been largely left behind; and the vast majority of people are naive realists. Even the indirect realists do not tend to be as strong in their position as Kant was: they tend to still think that how we perceive reality is predominantly a reflection of reality in-itself.

The problem is that you are not making any real objection to the idea that we cannot know the things-in-themselves: you are just sidestepping it by noting the uncontroversial fact that we can infer things from other things.

You have to remember, Kant divides the world into the phenomena and noumena (roughly speaking): propositions acquired through empirical observation are only valid as universally true for human experience. The inferences you are talking about are things Kant would place squarely in the phenomenal---not noumenal---world.

I am going to condense our conversation into one, to keep track of it better.

t’s affect is called sensation and its representation is called phenomenon, but the particular object itself, hasn’t yet been exposed to that part of the system which assigns conceptions. Which is to say, we don’t know yet what to think of that particular object impacting our senses.

This part is where you lost me. How is “its representation” not the end result of the judgments, concepts, and reason?

So even though the conscious subject to which experience belongs has no need to call the particular object that appears to the senses anything, insofar as he isn’t even conscious of the synthesis producing phenomena anyway, and to which Kant gives the term “…the undetermined object of empirical intuition…”, the system itself does need to call it something, in order for that which follows from it, to be a valid logical inference. As far as the system itself is concerned, then, to which being conscious or not has no meaning, that thing is called a transcendental object.

From my reading of CPR, the thing-in-itself is what impacts the senses.

Try thinking of phenomena as the signal traveling along nerves, say, output of the eye to the input to the brain. There is a signal, we have no awareness of it, but it is something, which we call intuition, and the information the signal carries represents whatever it was that impacted the sensory device to which the nerves connect, and that is called phenomenon.

This doesn’t seem coherent with Kant’s schema: Kant refers to what we end up seeing, hearing, etc. as phenomena. This is why I am trying to get you to answer what you call the end result which is a part of one’s experience; and I still have yet to hear an answer.

The whole idea of having, the only reason to have, a concept, is to represent that thing perceived, by a name. The name apple merely indicates how the thing perceived is to be known, which is called experience.

This is peculiar to me, as, then, the brain does not know the concept of quality; nor any of the twelve categories of the understanding—nor does the “understanding” if you want to avoid using the term “brain”.

I may be misunderstanding, but assuming I do, no, I would not agree. Faculties are function-specific members of a system described in a metaphysical theory. There’s no possible method by which those faculties can be found in a brain, they being merely logical constructs, and by the same token, there’s nothing empirically provable, hence nothing falsifiable, in a metaphysical theory. All that can be said, insofar as empirical verifications for non-empirical theories are out of the question, is the brain has nothing to do with abstract conceptions authorized by such theory.

Wouldn’t you agree, though, that the brain is the representation of the thing which has those faculties? It’s two sides of the same coin.

Why do I have to presuppose that objects effect my senses, when my sensations apodeitically prove my senses have been affected? If I can see a mosquito bite me, if I can smell the bacon I hear frying, why do I have to presuppose either one of those objects?

Because none of that is about things-in-themselves. If you agree that seeing a mosquito bite you indicates there is a mosquito, whatever it may be exactly, in reality in itself which impacted your senses; then you don’t believe we cannot know anything about things-in-themselves...for you just admitted that a mosquito is an animal which exists in reality in-itself.

And on the other hand, why subject myself to the absurdity of supposing what just bit me, or that stuff I’m about to consume, wasn’t an object at all?

Because the material world you experience is material because of the a priori way that you cognize it—re: space and time.

A thing in itself is not 'an object'. Its a logical concept.

A thing-in-itself is the concept of an object which we cannot know anything about: so it necessarily is an object. You make it sound like it is purely abstract: it is no more abstract than the concept of an object, which refers to a real object.

It seems like you agreed with me, so I am not following why you do not believe in a priori knowledge. If your representative faculties must already know how to do certain things and already has certain concepts at its disposal, then it must have a priori knowledge. Perhaps it has to do with:

Belief is a requirement for cognition. Knowledge is a potential result of cognition.

To keep things simple, let’s assume the traditional interpretation of knowledge: a justified, true belief.

You cognition must have more than a mere belief to know how to do what it does. E.g., your cognition has a priori knowledge on how to construct objects in space because it clearly does it correctly (insofar as they are represented with extension). The necessary precondition for the possibility of experiencing objects with extension is that your brain knows how to do that.

Or referring back to my original example, your reasoning would entail that it is irrational to believe that there is something moving under my bed covers.

No it would not. I was trying to entertain your analogy to help further the discussion, but it is technically a bad analogy: it is already littered with phenomenal knowledge and requires no knowledge of the things-in-themselves. You would have to give an example which posits inferred knowledge of a thing-in-itself from phenomena to demonstrate your point: it is uncontroversially true that we can infer about phenomena, or possible phenomena, from given phenomena (such as a ball being under the bed without seeing it).

The epistemic dualism that inevitably arises in indirect realism is exactly because the very idea of a bed, covers, and something being underneath them is phenomenal; and once you strip away the a priori means of cognizing them, there is no intelligible “bed” nor “covers” left.

What you are trying to do, mistakenly, is claim that you can infer the things-in-themselves like how you can infer something phenomenally from other phenomena: these are not the same at all.

I have no problem with saying that I can infer about things as it relates to phenomena; but inferring about things-in-themselves from phenomena is a contradicto in adjecto.

Your reasoning as it stands applies to believing in anything that one cannot directly perceive, and so would call into question almost all of science (especially particle physics).

In the CPR, an object which our sensibility is incapable of sensing, or which our understanding is incapable of cognizing, are noumena: they are sub-species of things-in-themselves. Noumena are equally unknowable as any other things-in-itself: your sensibility, intuition, and cognition are only capable of knowing things as it is a priori structured to.

Now, if by science you are smuggling in scientific realism, then, yes, I think a transcendental idealist would have to be a scientific anti-realist of sorts; but this does not mean that science isn’t applicable to phenomena. In fact, that’s exactly what Kant argued—viz., science is grounded in a priori principles and of which are only universally true for human experience. That’s kind of the whole point Kant is trying to argue for: the synthesis of rationalism with British empiricism.

Even the direct realist (if also a scientific realist)

You are equivocating: one can be a direct realist without being a scientific realist. Every direct realist must be an empirical realist—albeit it rare, they could reject the scientific process of study. EDIT: Ignore this part: I read it wrong.

How can you know that you exist at all? That you exist itself also requires inherent trust of one's experience: we experience in a way where there seems to be an 'I' vs. 'other'.

Let's go down this path which you are describing: I think that will be beneficial. What about your perceptions do you think gives you accurate enough information to make an inference about reality as it is in-itself?

Sorry for the belated response!

I do not believe 1+1=2 is apriori for example.

The metaphysical underpinnings for “1 + 1 = 2” is that our brains construct our conscious experience according to math insofar as the plotting of objects in space is inherently mathematical.

Of course, the other alternative would be just say that math is a way that our over-arching faculty of reason nominally parses our conscious experience—which is the strongest version of mathematical anti-realism.

IE, that people are capable of doing logic is innate, but the practice of classical logic specifically must be learned.

That logic is a priori does not entail that we can perform, intellectually, logic properly since birth. These are separate considerations: the former is about how inherently logical our conscious experience is, the latter is about how logically sound our over-arching reason is at argumentation and reasoning.

Close, but not quite. A dog can experience a thing as well, but it cannot come up with the idea of "a thing in itself". That requires language, thinking, debate, etc. It is not an innate conclusion, but one of applied reason.

The point is that a thing-in-itself is the thing as it is in-itself: of course, it is a separate note that one may not have any self-reflective knowledge of it. Knowledge is, though, a requirement for cognition: your brain has to know how to do things and how to apply concepts and what not in order to construct the conscious experience you are currently having.

Since we can only observe representations, how do we know there's something under those representations? We only know because sometimes, the world contradicts our interpretations. Therefore the only logical thing we can conclude is that there must be something beyond our perceptions and interpretations that exists. Its not a proof of "I see the thing in itself" its a proof of, "Its the only logical conclusion which works."

Nothing about what we think is going to happen, self-reflectively, nor its contradiction entails that there is an object which impacted our senses (and of which we are experiencing). You seem to be conflating the faculties which produce our experience with our self-reflective knowledge of that experience. Viz., I may be wrong that this object next to be is red, but that my experience contradicts me is not the same as reality contradicting me.

To me, I would agree that the best explanation, given experience, is that there are objects impacting our senses: but that is derived from empirical data from (ultimately) our experience itself. E.g., I experience getting knocked out by a ball, I experience an optical illusion, I study biology, etc. This is not inherently a process of reality contradicting me: it is me confirming hypotheses through empirical study.

Its not necessarily about trust, its about experience. You and I have both had instances in our lives where our perceptions and beliefs about the world were contradicted in unexpected ways. Thus we conclude that there is something that exists apart from our understanding and perceptions.

Wouldn’t you agree that you have to trust your experiences, to some degree, to even posit that reality sometimes contradicts your perceptions?

Good discussion as usual Bob! I always like how you drill in. I'm heading out on vacation this week to Yellowstone park with some friends, so I won't be available to reply for a while. I'll read your reply when I get back for sure. Until then, stay great and I hope the discussion is interesting!

No worries at all!

The problem is that you have hidden the paradox, but it is there in your example. Either you trust the evidence you are using to infer whether or not there is such a thing under your bed, and what it is, or you do not. If you do, then you are trusting that evidence to give you accurate information about the "under the bed as it is in-itself": if you deny that have any such trustworthy evidence, then you have not reason to believe you can infer, other than blindly and absurdly, what is under there.

There is no doubt in my mind that this visual experience has been caused by something external to the visual experience itself
…
It seems part of the a priori structure of the brain to expect that everything that happens has a cause. This cause may be called the thing-in-itself.

Assuming by thing-in-itself we mean the object qua itself (independently of our experience of it), it sounds like you are denying that you cannot have any knowledge of the things-in-themselves; which cannot be true if there is an a priori structure by which your brain intuits and cognizes objects (which you equally affirmed).

This doesn’t seem coherent to me.

In other words, the conception alone is not knowledge.

Hmmm, I don’t buy it. The concept of an apple is knowledge of what an apple is—that’s part of the whole idea of having a concept of an apple.

If I see a ball, I don’t call it either of those you mentioned. I call it a ball iff I already know it as such, or, if you inform me that’s what that thing I see, is.

That’s fair. Again, as I noted in your DM: that’s besides the point.

And I didn’t say whatever our brain says it is; I said whatever our understanding says it is, insofar as the faculty of understanding, in its full procedural operation, thinks, judges and cognizes….all those systemic artifices which are grounded in logic as opposed to being grounded in external reality and externally affected physiology, and internal reproductive imagination, re: intuition, the sum of which is called sensibility.

I get why you went that route, but wouldn’t you agree the brain is the representational knowledge of those faculties?

but does presuppose nonetheless, that the human individual is of such a nature as to have representational faculties imbued in a system by which any knowledge at all is possible.

But, then, you have to concede that you have to trust your conscious experience to derive that that experience is representational—no?

Otherwise, you are just blindly presupposing that objects effect our senses—there’s nothing, without the aid of experience, that can be used transcendentally to determine that.

I do not see all these claims as being about the world as it is in itself.

I can see that to some extent—e.g., the faculty of understanding is not a comment on what such exists as in reality as it is in-itself.

Could it be that the biggest problem for indirect realists, is being called indirect realists?

What would you call it, then?

Kant doesn't speak of brains, neuroscience, genetics, etc. when making his case.
…
Kant's arguments are based on "what must be necessary for thought to exist as such."

That’s fair, I use those terms to explain it because it is easier to convey to other people. Most people have never heard of transcendental approaches to truth.

this is why the "paradox" shows up—it's the result of mixing Kant's conclusions with empiricist arguments about the way perception is shaped by biology, physics, etc.

Could you elaborate on this part? I still think there’s a paradox even if you speak in purely Kant’s terms. We only know that objects are a necessary precondition for our experience IF we trust our experience to some extent—which he then turns around and denies is possible. I think this might be, although I am not familiar with Hegel’s critique, what you are referring to with Hegel:

Now, the other thing you get at is that Kant does seem to dogmatically assume that perceptions are of objects. That's Hegel's big charge, worked out in the Logic. Hegel agrees that perceptions are of objects, but he thinks that starting out by presupposing this is how Kant ends up with the noumenal and his dualism problem.

This sounds like Hegel identified the paradox as “dualism problem”. How does Hegel resolve this issue then? That might help resolve it here.

I apologize for the belated response! My schedule got hectic.

The way in which we know our own being, and the way we know the existence of other objects, is
different.

Correct. But:

I think that Kant agrees with Descartes that knowledge of our own being is apodictic i.e. it cannot plausibly be denied, as it is a condition of us knowing anything whatever (cogito ergo sum)

Kant clearly denies the cogito ergo sum argument, and argues in the CPR that we cannot know anything about the self as it is in-itself because our self-consciousness, albeit it different, is still representational. It is important to remember that Descartes was arguing for the self as a simple substance; and Kant was arguing for the self as the unity of apperception, which has transcendental validity insofar as it is necessary for constructing our conscious experience:

The proposition, “I think,” is, in the present case, understood in a problematical sense, not in so far as it contains a perception of an existence (like the Cartesian “Cogito, ergo sum”), ["I think, therefore I am."] but in regard to its mere possibility – for the purpose of discovering what properties may be inferred from so simple a proposition and predicated of the subject of it.
…
That the I or Ego of apperception, and consequently in all thought, is singular or simple, and cannot be resolved into a plurality of subjects, and therefore indicates a logically simple subject – this is self-evident from the very conception of an Ego, and is consequently an analytical proposition. But this is not tantamount to declaring that the thinking Ego is a simple substance – for this would be a synthetical proposition. The conception of substance always relates to intuitions, which with me cannot be other than sensuous, and which consequently lie completely out of the sphere of the understanding and its thought: but to this sphere belongs the affirmation that the Ego is simple in thought. It would indeed be surprising, if the conception of “substance,” which in other cases requires so much labour to distinguish from the other elements presented by intuition – so much trouble, too, to discover whether it can be simple (as in the case of the parts of matter) – should be presented immediately to me, as if by revelation, in the poorest mental representation of all.

– CPR: https://www.marxists.org/reference/subject/ethics/kant/reason/critique-of-pure-reason.htm#:~:text=That%20the%20I%20or,mental%20representation%20of%20all.

If all you are noting is that Kant believed that there must be something which exists which is producing the conscious experience which I have, then that is true; but this is not the same as the cogito argument (in its original argumentation).

This is critical because nothing I said that you quoted denies the ‘I’ as the unity of apperception; and Kant is denying any knowledge of the self as it is in-itself. So, the paradox again arises such that I cannot trust even my own internal sense to give me information about what I am in in-itself and yet I can trust it enough to know that I am at all—seems problematic, no?

An object with no definite properties is not an object at all. To be an object is to have properties.

My point was that that we could say there is an object, but nothing about what it is—nothing about its properties. I just worded that confusingly.

Again, the key difference about knowledge of objects, and knowledge of your own faculties

Hopefully the above helps clarify why this does not resolve the paradox. Viz., if you can trust your internal sense enough to give you accurate enough information to know you exist [with representative faculties], then you necessarily can know some information about how the world really is.