home | what's new | other sites | contact | about

Word Gems 

self-knowledge, authentic living, full humanity, continual awakening 

Immanuel Kant

Critique of Pure Reason

The Metaphysical Exposition of Space

return to 'Kant' main-page

Commentary by ChatGPT

The Metaphysical Exposition of Space

We have now reached Kant's first sustained argument about space. This is an important moment in the Critique, because Kant is no longer merely telling us what he thinks. He is going to argue for it.

His target is a deceptively simple question:

Is space something we learn from experience, or is it already presupposed by experience?

Kant's answer will be:

Space is a priori, and it is an intuition rather than a concept.

The Metaphysical Exposition consists of four arguments in the A edition (1781), with a fifth formulation appearing in the B edition (1787).

We should take them slowly, because they are cumulative rather than merely repetitive.

1. What Does "Metaphysical Exposition" Mean?

The title itself needs decoding.

We already know that exposition means something like:

laying out or making explicit what is contained in a concept.

Kant is therefore going to examine our representation of space and ask what can be discovered about it simply by analyzing the idea itself.

And metaphysical, in this context, means that he is investigating something prior to particular empirical observations.

He isn't measuring space.

He isn't conducting an experiment.

He is asking what the very possibility of representing space reveals about its status.

So:

Metaphysical Exposition of Space = an analysis of our representation of space intended to discover its fundamental character.

Restatement:

What does Kant mean by "exposition"?

In ordinary language, if someone says:

"Let me expose my idea to you,"

they mean:

"Let me lay it out so that you can see what is contained in it."

That is basically what Kant means by Exposition here.

He starts with something we already possess: our representation of space. He then examines that representation and asks:

What can we discover about the nature of space simply by examining how space is necessarily represented by us?

He is not yet doing physics. He isn't measuring distances or asking what space is made of.

He is doing something more like philosophical dissection.

Take our ordinary experience

Suppose you look around the room.

You don't merely encounter:

desk
chair
lamp
wall

You encounter them as:

desk here
chair there
lamp beside the desk
wall behind everything.

There is a spatial framework within which all these objects are apprehended.

Kant asks us to turn our attention away from the individual objects and toward that spatial framework itself.

That's the "exposition."

He is saying, in effect:

Let's examine what is already contained in our representation of space.

Then what does "fundamental character" mean?

Kant wants to determine what kind of thing space is.

Is it:

1. Something learned from experience?

Or:

2. Something already presupposed by experience?

And:

3. Is space a general concept?

Or:

4. Is space an intuition—a direct mode of presentation?

Those are questions about the fundamental character of space.

So we could replace my earlier sentence with something much clearer:

Metaphysical Exposition of Space = Kant examines the way space is necessarily represented by us and asks what this reveals about the basic nature of our representation of space—whether it is empirical or a priori, and whether it is a concept or an intuition.

That is much better.

But there is an even deeper point

The word "our" is crucial.

Kant isn't saying:

"I have examined the universe and discovered that space is a priori."

He's saying something more like:

"I have examined what is necessarily involved in our representation of space, and from that I can determine something fundamental about space as it is available to human cognition."

This is why the word transcendental matters.

He is investigating:

not space by itself,

but

space as it relates to the possibility and structure of human experience.

And this is why our earlier discussion about the "camera in the head" is so relevant.

Kant is asking us to stop assuming that:

first there is a fully formed spatial world → then the mind photographs it.

Instead, he asks:

What is already built into the very act by which spatial objects can appear to us?

That is the question driving the Metaphysical Exposition.

So I'd now give you this as the clean formulation:

The Metaphysical Exposition of Space

Kant takes our ordinary representation of space and examines it closely. He asks what must be true of that representation itself: Is space learned from experience, or is it already presupposed by experience? Is it a general concept, or an immediate intuition? By answering these questions, Kant seeks to establish the fundamental character of space as it is necessarily represented by the human mind.

That is what I meant by "exposition," and I agree that we should make this explicit before proceeding through Kant's individual arguments.

2. Kant's First Argument: Space Is Not an Empirical Concept

Kant begins:

“Space is not an empirical concept which has been derived from outer experiences.”

— A23/B38

This is his first move.

Why?

Because, he argues, spatial experience already presupposes space.

We encounter:

one object beside another
one object outside another
one object above another.

But in order to experience these relationships as spatial relationships, we must already have some representation of space.

So Kant's argument is essentially:

Experience teaches us about particular things in space, but experience cannot be the original source of the framework of space itself, because spatial experience already presupposes that framework.

Plain English

You cannot learn space itself simply by collecting spatial experiences if the ability to have those spatial experiences already requires a representation of space.

3. An Example

Imagine that someone says:

"I learned what space is by looking at objects."

Ask:

How did you recognize those objects as being beside, above, below, inside, or outside one another?

The answer seems to require some prior spatial framework.

You didn't first experience:

objects

and then discover:

"Ah! There is something called spatial arrangement."

The spatial arrangement was already part of the experience.

This is Kant's first major insight.

4. Kant's Second Argument: We Cannot Represent the Absence of Space

Kant next says:

“Space is a necessary a priori representation, which underlies all outer intuitions.”

— A24/B38

Then comes the crucial thought:

“We can never represent that there is no space, although we can very well think that there are no objects to be found in it.”

— A24/B38

This is a remarkably powerful distinction.

We can imagine:

an empty room.

There are no objects.

No table.

No chair.

No tree.

No person.

But we still imagine:

space.

Now try the reverse.

Imagine:

objects, but absolutely no space whatsoever.

That is much harder.

You can remove the objects from space.

But can you remove space itself while retaining the representation of external objects?

Kant says no.

5. The Argument in One Sentence

Kant's reasoning is:

We can imagine space without objects, but we cannot imagine objects outside space.

Therefore:

space is not derived from our experience of objects.

Rather:

the experience of objects already presupposes space.

This is the first major piece of Kant's case.

6. A Very Important Caution

We should not turn this into:

"Therefore space exists only inside the brain."

That is not yet Kant's argument.

He is making a claim about the conditions of human experience.

The argument is:

Whatever an external object may be independently of us, we cannot experience an external object except spatially.

This is the distinction we've been preparing for throughout our discussion.

We experience:

objects-as-spatially-presented-to-us.

We do not thereby acquire knowledge of:

things as they are independently of the conditions of our sensibility.

7. Kant's Third Argument: Space Is Not a Concept

Now Kant changes the question.

Suppose space isn't learned from experience.

Perhaps it is a concept that the mind constructs.

Kant rejects this.

He writes:

“Space is not a discursive or, as we say, general concept of relations of things in general, but a pure intuition.”

— A24/B39

This is where our earlier work on Anschauung becomes indispensable.

Remember:

Anschauung = direct or immediate presentation.

Kant's claim is:

Space is not fundamentally a general concept abstracted from many particular spaces.

Instead, space is a single, unified intuition within which particular spaces and spatial relationships are represented.

8. Why Does Kant Think Space Is an Intuition?

Consider:

this room
that room
a street
a field
the space between two objects.

We can think about particular spatial regions.

But Kant says that we don't construct the totality of space by adding these individual regions together.

Rather, we think of particular regions as parts within one encompassing space.

That is why he says:

“All geometrical principles, e.g. that in a triangle the sum of two sides is greater than the third, are never derived from general concepts of line and triangle, but only from intuition.”

— A25/B39

The point is that geometry deals with spatial constructions, not merely verbal definitions.

The triangle example is actually one of Kant's most important pieces of evidence, because it lets him show the difference between a concept and an intuition in a concrete way.

Kant writes:

“All geometrical principles, e.g. that in a triangle the sum of two sides is greater than the third, are never derived from general concepts of line and triangle, but only from intuition.”
— Critique of Pure Reason, A25/B39

Let's unpack exactly what he means.

1. Start with the concept of "triangle"

Suppose I give you the definition:

A triangle is a three-sided plane figure.

That's a conceptual definition.

From the concept alone, I know:

• it has three sides;
• its sides are line segments;
• it encloses a region.

But Kant asks:

Can I derive the actual geometrical properties of triangles merely by analyzing the word or concept "triangle"?

He says no.

Something more is required.

2. Geometry requires that we construct the triangle

Imagine drawing this:

       /\
      /  \
     /    \
    /______\

Now something has happened that did not happen merely by thinking the definition.

We have constructed a particular triangle in intuition.

We can see its:

• three sides;
• angles;
• spatial relationships;
• relative lengths;
• interior and exterior.

And we can perform geometrical operations upon it.

This is what Kant means when he says geometry proceeds through intuition.

3. But here's the really interesting part

You might object:

"Fine. I drew a triangle. But that's just another empirical experience. I took a pencil and drew lines on paper."

Kant's answer would be:

The physical drawing isn't the important thing.

The paper, pencil, ink, and particular dimensions are empirical.

But the spatial construction is something different.

When the geometer reasons about a triangle, she isn't interested in this particular physical triangle as an object of nature.

She is able to construct and consider:

a triangle as such

within spatial intuition.

And this is where Kant's argument becomes interesting.

4. Consider the famous 180-degree proposition

Euclidean geometry tells us:

The three interior angles of a Euclidean triangle add up to 180 degrees.

Kant asks:

Where does this knowledge come from?

It doesn't seem to come merely from the definition:

"three-sided figure."

The definition doesn't contain "180 degrees."

Nor did we have to measure every triangle in the universe.

We construct a triangle in spatial intuition and discover its necessary geometrical relationships.

This is why Kant connects geometry to pure intuition of space.

5. Here's the distinction we need

Suppose I say:

All bachelors are unmarried.

That's a conceptual proposition.

The concept bachelor already contains the relevant meaning:

bachelor → unmarried man.

I don't have to draw anything.

I don't have to construct anything in space.

I simply analyze the concepts.

But:

The angles of a triangle sum to 180 degrees

is different.

The concept triangle does not simply contain "180 degrees" as part of its definition.

We need to construct the triangle in spatial intuition and investigate its spatial structure.

That is why Kant considers geometry a crucial example of synthetic a priori knowledge.

6. And now we see why space matters

Kant's reasoning is roughly:

Geometry gives us necessary truths about spatial objects.

Those truths aren't simply extracted by analyzing concepts.

Yet they aren't derived by measuring the physical world either.

They depend upon our ability to construct objects within pure spatial intuition.

Therefore:

Space must be something more fundamental than an empirical collection of spatial observations.

It is a structure within which geometrical construction is possible.

7. This connects directly with your earlier "dog" example

This gives us an especially nice three-way comparison.

DOG

You encounter:

dog 1
dog 2
dog 3

You abstract common characteristics:

DOG

That's a concept.

TRIANGLE AS A CONCEPT

You define:

three-sided figure.

Again, that's conceptual.

TRIANGLE IN GEOMETRY

But now you construct a triangle in spatial intuition.

You can then investigate relationships that aren't simply contained in the verbal definition.

That is the crucial difference.

8. And this is why "intuition" was such an unfortunate English word for us

If we hear:

"Geometry depends on intuition,"

we may think:

"I have an intuitive feeling that this triangle is right."

That's almost exactly the wrong idea.

Kant's Anschauung is much closer to:

"I can construct and directly behold the spatial object."

So perhaps our preferred translation here should be:

Geometry depends upon direct spatial presentation.

Or:

Geometry works by constructing figures within the immediate intuition of space.

That makes Kant much easier to understand.

9. One more fascinating point

This is also where our later discussion of Einstein and non-Euclidean geometry will become extremely interesting.

Kant is writing in a world in which Euclidean geometry was regarded as the necessary structure of physical space.

But modern physics raises a distinction Kant could not have anticipated in its present form:

The mathematical structure we can construct in pure geometry is not necessarily identical with the actual geometry of physical spacetime.

That doesn't automatically destroy Kant's argument about human spatial representation. But it forces us to ask a very important question:

Is Kant proving something about the structure of human spatial intuition, or is he also proving something about the actual structure of physical space?

Those are not the same proposition.

And I think we should keep that question quietly in the background as we proceed. It will become especially valuable when we eventually bring Einstein and relativity into our Kant study.

However, my phrase:

       A
      / \
     /   \
    /     \
   B-------C

Restatement:

The phrase “that is why” was too strong and skipped a step.

What is the actual connection?

Kant is trying to distinguish a concept from an intuition.

A concept is general. We can arrive at a general concept by recognizing what several individual things have in common.

For example:

this oak
that maple
that pine

→ we abstract their common characteristics

→ TREE

The concept tree is therefore general. It can apply to many individual trees.

Kant says space does not work that way.

We don't encounter:

this little space
that little space
another little space

and then abstract their common characteristics to arrive at:

SPACE

Instead, Kant thinks the relationship runs in the opposite direction.

We encounter particular spaces as portions of a larger spatial whole.

For example:

this room is in space.

the room next door is in space.

the entire building is in space.

And the two rooms aren't two independent examples from which we abstract the concept space. Rather, we understand each room as a bounded region within one space.

That is the crucial observation.

Kant puts it this way

“All parts of space coexist ad infinitum.”

And:

“Space is essentially one.”

The idea is that particular spaces are limitations of one underlying spatial field, rather than independent instances from which we construct a general concept.

This is why Kant concludes that space is more like an intuition than a concept.

Here's a very simple contrast

Concept

Think:

DOG

You can have:

dog A
dog B
dog C

and from them form the general concept DOG.

The individual dogs are instances of the concept.

Space

Kant says the relationship is different:

SPACE

contains:

this region
that region
another region

The particular regions are parts of space.

They aren't independent examples from which we construct the general idea of space.

That's the connection I should have spelled out.

Ed: Yes, there is no underlying unifying "field of Dog"

And this is why Kant's "infinite given magnitude" matters

His next step is quite radical.

He says:

“Space is represented as an infinite given magnitude.”

Think about what happens when you imagine a room.

You can imagine:

the room

then:

the building

then:

the neighborhood

then:

the city

then:

the Earth

then:

the solar system

and so on.

You can keep extending the spatial field.

But Kant's point is that you don't have to construct space by actually completing this infinite expansion.

You already possess the representation of space as a whole, and particular spaces are conceived as limited regions within it.

That is why Kant thinks space has the character of an intuition rather than a general concept.

So I would rewrite my earlier sentence

Instead of:

“That is why he says...”

I would say:

Kant now uses this feature of our representation of space to distinguish space from a general concept. A general concept is formed by bringing together individual instances under a common idea. Space, Kant argues, is represented differently: particular spaces are apprehended as bounded regions within one encompassing space. We do not construct the whole of space by adding particular spaces together; rather, we represent particular spaces as parts of an already given spatial whole. This is one reason Kant classifies space as an intuition rather than a concept.

That is the actual logical bridge.

And I think this is a good example of the kind of thing we need to watch for throughout Kant: the conclusion may be perfectly understandable, but the connective tissue between premise and conclusion can disappear inside one of his sentences. Our job is to put that connective tissue back in.

9. Kant's Fourth Argument: Space Is an Infinite Given Whole

Kant then makes his most striking statement:

“Space is represented as an infinite given magnitude.”

— A25/B39

This is important.

We can represent:

a small space,

a larger space,

an enormous space.

But every particular spatial region seems to be within a larger spatial whole.

We don't construct infinite space by first assembling infinitely many little spaces.

Rather, Kant says the whole space is presupposed, and particular spaces are limitations or portions of it.

This supports his conclusion that space is an intuition, not a concept.

10. The Four Arguments Together

We can now see the architecture.

Argument 1

Space is not learned from experience because spatial experience already presupposes space.

Argument 2

We can represent space without objects, but we cannot represent outer objects without space.

Therefore space is a priori.

Argument 3

Space is not a general concept assembled from particular spaces.

Therefore it is an intuition.

Argument 4

Particular spaces are represented as portions of one encompassing space.

Therefore space is represented as an infinite given whole, consistent with its being an intuition rather than a concept.

11. Kant's Conclusion

Kant has now reached the proposition that will govern the remainder of the Aesthetic:

Space is an a priori intuition.

Those three words contain a remarkable amount of philosophy.

A priori

It is not derived from particular experiences.

Intuition

It is a direct form of presentation, not a general concept.

Space

It is the fundamental form through which we apprehend outer objects.

So, in plain English:

We don't first experience objects and then construct the idea of space. Rather, our capacity to experience external objects already operates spatially.

12. Three Direct Passages from Kant

1.

“Space is not an empirical concept which has been derived from outer experiences.”

Plain English:
We don't build the fundamental idea of space by accumulating experiences of objects.

2.

“We can never represent that there is no space, although we can very well think that there are no objects to be found in it.”

Plain English:
We can imagine an empty space, but we cannot successfully imagine spatial objects while eliminating space itself.

3.

“Space is not a discursive or, as we say, general concept of relations of things in general, but a pure intuition.”

Plain English:
Space isn't a general idea abstracted from many examples. It is the fundamental framework within which spatial things can be directly presented.

The Argument in Our Own Language

I would put this in especially simple form:

Kant asks us to notice something strange: we can remove every object from space and still represent space; but we cannot remove space and still represent an outer object.

From this, Kant argues that space cannot have been learned merely by observing objects. Space must already belong to the structure through which outer objects can be experienced.

He then adds that space is not a general concept assembled from many particular spaces. It is an immediate, unified intuition within which particular spatial regions are represented.

His conclusion: space is an a priori intuition—the fundamental form through which human sensibility apprehends objects as external and spatially related.

One Question We Should Not Let Go

Kant's argument is elegant. But does it prove everything he wants it to prove?

In particular:

Does showing that space is necessary for human experience establish that space has no reality independently of human cognition?

That is the question we should carry into the Transcendental Exposition of Space.

There Kant will move from:

What can we discover by analyzing our representation of space?

to the much more ambitious question:

What can we establish about the status of space itself?

And that is where Kant's argument becomes even more consequential.

    /\
   /  \
  /____\

Ed: Ok, that’s a good question – but let me recap all this to see if I understand Kant’s reasoning in bringing up the triangle example – which seems to have been offered almost as a self-evident example, and I’m not sure if it rises to that level of clarity, but, in any case, my recap is:

Kant says “a triangle the sum of two sides is greater than the third, are never derived from general concepts of line and triangle, but only from intuition.” He’s saying that for a geometer  to actually perceive that the sum of two sides of a triangle is greater than the third one needs to empirically or mentally construct a triangle and obtain information about the triangle by working with it. This means that the construction of the triangle will of necessity occur in “space”; meaning, there needs to be already in place some aspect of “space” for this to happen. This means that geometry presupposes “space”. And this is why space is an a priori structure. Is this the argument?
 

Chat: Yes — that is essentially Kant's argument, and I think your recap has now got the important structure. But I would make two refinements, because they make the argument considerably more precise.

Your reconstruction, step by step

You have:

1. Geometry cannot obtain its geometrical truths merely by defining concepts.

Correct. The concept triangle tells us what a triangle is, but the geometrical relationships aren't simply contained in the definition.

2. The geometer therefore constructs a triangle, either physically or mentally, and works with it.

Yes, with one Kantian preference: the physically drawn triangle is not fundamental. The essential construction can occur in pure spatial intuition—in thought.

3. The construction necessarily occurs in space.

Yes—but here's the crucial refinement:

It isn't merely that the geometer happens to put the triangle somewhere in space.

Rather, the triangle's very constitution as a geometrical object consists of spatial relationships: lines have length and direction; points have position; angles are spatial relations; one line intersects another, etc.

4. Therefore geometry presupposes space.

Yes.

And now comes the step Kant really cares about:

5. If geometry presupposes space, then space cannot itself be something learned from the geometrical objects we construct.

That's the crucial move.

We don't first learn space by observing triangles and then use our acquired concept of space to do geometry.

Rather:

We must already have the spatial framework in order to construct and apprehend the triangle as a geometrical object at all.

Therefore:

6. Space is a priori.

That is the argument.

But there's one thing I would change in your wording

You said:

"to actually perceive that the sum of two sides of a triangle is greater than the third..."

I'd change perceive to apprehend or demonstrate.

Why?

Because Kant isn't saying that we look at a triangle and visually notice:

"Ah! Two sides are longer than the third."

That would sound like an empirical observation.

He's talking about a geometrical demonstration.

The geometer constructs the figure and reasons through its spatial relationships. The resulting knowledge is not:

"I've looked at enough triangles and they all seem to behave this way."

It is:

"Given the geometrical construction, this relationship necessarily follows."

And that necessity is what makes the example important to Kant.

Here's the argument in its cleanest form

I think we can now write it this way:

Kant points to geometry because geometrical knowledge cannot be obtained merely by analyzing definitions. The geometer must construct spatial figures and investigate the relationships embodied in them. This construction can occur mentally, but it must occur within a spatial representation. Thus geometry presupposes space: we must already possess a representation of space in order to construct and reason about geometrical figures. Space therefore cannot itself be derived from those experiences; it is a condition that precedes them. Kant calls this condition an a priori intuition of space.

That, I think, is the version you've been looking for.

And there's an important distinction we should preserve

Geometry presupposes space.

does not yet, by itself, establish:

"Therefore space is a priori intuition."

It gets us very close, but Kant needs his other arguments to complete the case.

The triangle example particularly helps him establish the intuition side:

Geometry operates through direct spatial construction, not merely through general concepts.

His earlier arguments help establish the a priori side:

Space is already presupposed by outer experience and cannot be derived from that experience.

So the four arguments are doing somewhat different jobs.

And that, I think, is why the triangle example had seemed so mysterious: we were asking it to prove the entire proposition "space is an a priori intuition," when Kant is actually using it to illuminate one part of that proposition—especially the difference between space as an intuition and space as a general concept.

Ed: “And metaphysical, in this context, means that he is investigating something prior to particular empirical observations.” Metaphysical usually means something else, the kinds of questions “transcendent” points to. Why call it metaphysical? Is this another example of ill-placed definition?

Chat: Yes — you've identified another terminological trap, although this one is a little different from Kant's use of "transcendental."

My earlier sentence—

“metaphysical, in this context, means that he is investigating something prior to particular empirical observations”

—is too loose. It makes "metaphysical" sound almost synonymous with "a priori," and that is not what Kant means.

What does Kant mean by "metaphysical" here?

Kant is using metaphysical exposition in a more specialized sense.

He is asking:

What can be established about our representation of space by analyzing it, rather than by investigating particular empirical instances of space?

So "metaphysical" points to an inquiry into the fundamental character or status of something, rather than an empirical investigation of particular cases.

That is why he calls it a metaphysical exposition.

But your objection remains important:

Why not simply call it a transcendental exposition?

Because Kant actually uses both terms, and he gives them different jobs.

Metaphysical vs. Transcendental Exposition

This distinction is worth getting exactly right.

Metaphysical Exposition

Kant examines the concept/representation of space itself and asks what follows from analyzing it.

His questions include:

Is space empirical or a priori?

Is space a concept or an intuition?

The four arguments we have just been examining are doing this work.

Transcendental Exposition

Then Kant asks something different:

Can we explain how certain a priori knowledge is possible by reference to our representation of space?

His example will be geometry.

In other words:

Metaphysical Exposition:

What is space, as represented by us?

Transcendental Exposition:

What does the possibility of geometrical knowledge tell us about the status of that representation?

That's a much cleaner distinction.

And this helps explain the word "metaphysical"

The traditional meaning of metaphysics is indeed much broader than what we are discussing here.

It concerns fundamental questions such as:

What is reality?

What exists?

What is substance?

What is causality?

Does God exist?

What is the nature of the soul?

So your instinct is correct: "metaphysical" ordinarily carries a much larger and more transcendent flavor.

But Kant is trying to reconstruct metaphysics itself.

He wants metaphysical investigation to stop pretending that it can simply leap beyond experience and pronounce upon things-in-themselves.

Instead, he asks:

What can reason legitimately establish about the fundamental conditions of human cognition?

Thus his "metaphysics" is not necessarily:

"Let's go beyond the world and speculate about ultimate reality."

It can instead be:

"Let's investigate the fundamental structures that make knowledge of the world possible."

That's still metaphysical in the sense that he's investigating fundamental conditions and principles, rather than particular empirical facts.

So was Kant guilty of "ill-placed definition"?

I'd put it slightly differently.

He is not misusing the word arbitrarily, but he is using an established philosophical word in a narrower and reoriented sense.

And I think your larger pedagogical criticism remains entirely valid:

A reader encountering "metaphysical exposition" naturally brings the ordinary philosophical meaning of metaphysics with him. Kant then uses the word in a specialized way without that meaning being immediately transparent.

That's exactly the kind of terminology we should flag rather than simply memorize.

And it gives us a useful rule for our study:

Whenever Kant uses a familiar philosophical word in a specialized sense, we should distinguish the ordinary meaning from Kant's technical meaning before proceeding.

One final clarification

I would not say:

Metaphysical = prior to experience.

That's too crude.

Rather:

A priori describes the source/status of knowledge—not derived from experience.

Metaphysical describes an inquiry into fundamental principles or conditions, traditionally concerning reality and the ultimate structure of things.

Transcendental describes Kant's particular investigation into the conditions that make our knowledge or experience possible.

Those three concepts overlap in Kant's project, but they are not synonyms.

And I think we should put that distinction into our Glossary now, because we're going to encounter all three repeatedly.

Ed: “He is asking: What can be established about our representation of space by analyzing it, rather than by investigating particular empirical instances of space?” But, “analyzing it” is “empirical”
because “empirical” means “observation” which is “analyzing”. This does not help us, but maybe this is part of the systemic confusion of Kantian terminology.