Two mistakes in the one title!

Just to check, there is a common misapprehension of relativity that thinks it says that truth is relative to the observer. That view is of course exactly the opposite of what the theory actualy says.

You haven't misunderstood, have you?

It's just that more typically, folk take Einstein to have undermined Kant's view of time...

Einstein didnt say truth was relative, but that the world was. The question of how to deal with the new situation in modern thought is phenomenology. Psychologically, however, we are not satisfied with the world. Heidegger puts us in a dire situation with the picture he paints. Hegel's absolute knowledge was rejected by him. Knowing all truth has be an aspiration though of religious seekers and philosophers for ever. Personally is see truth, subjectively, as personal or relational. for others it might be more abstract. Have you ever felt you want everything?

Donald Hoffman and many others show how different reality is from our perception. It is philosophy which says reality bounced back to us and is exactly as it appears. This subjective move, I suspect, leads to infinite knowledge

Special relativity: The laws of physics are the same for all inertial frames of reference. I.e. there is no difference in the laws of physics no matter how fast or in which direction you are travelling.
General relativity: The laws of physics are the same for all inertial and non inertial frames of reference. I.e it does not matter even how much you accelerate, the laws of physics are constant.
If by the phrase "what Einsten said" you mean "Special and General relativity" neither entail the world is relative to anything.

And Banno is correct, many people assume that General Relativity undermines Kant's conception that space is a form of intuition, since for Kant it seems the form of our space had to be Euclidean, whereas one result of General Relativity, and one which has been experimentally confirmed I believe, is that our space is non Euclidean.

And Banno is correct, many people assume that General Relativity undermines Kant's conception that space is a form of intuition, since for Kant it seems the form of our space had to be Euclidean, whereas one result of General Relativity, and one which has been experimentally confirmed I believe, is that our space is non Euclidean. — jkg20

Of course, all the non Euclidian spaces are mathematical constructions that can be thought, but cannot be perceived. Kant really only talks about our experience of space, and so long as no-one experiences a four-dimensional space, that still holds.

But of course that all depends on just what mathematics actually are. If you think it's a construct of the mind, it has little bearing on Kant's argument (aside from making his examples look dated). If you think math is the "language of the universe" it's a different matter.

I'm no expert on Kantian exegesis, but I'm aware that some people understand Kant in ways that make his position coherent with General Relativity.

:up:

For Einstein something does not have a definite position and size

For Einstein there is no overarching space or time for the relative to fit in. I said in the OP Kantian disagree

Hegel's move was to find the noumena in the world. He thought the origin of the universe was a collision between nothing and being, this the world is becoming as the result. Through becoming we can see the being it comes from, the noumena. Buddhism seems to say that thinking of nothing is wisdom. It's comforting to think of nothing, but I prefer hegels cognitive approach. I want all knowledge in this lifetime, the form of the Absolute

For Einstein something does not have a definite position and size

I think you might be confusing Einstein with Bohr, or some other early quantum mechanist. Let's have another stab at this, if only to save the scientific reputation of Einstein.

The idea of definite position and definite size in Einstein's theories of relativity make perfect sense. Given a coordinate system, you can pinpoint exactly where something is and you can state precisely what laws will determine the progress of that particle through space and time as measured from that coordinate system. What Einstein did say is that, in regards to those laws of physics, there is no preferred coordinate system: choose any coordinate system you like, the laws regarding what will happen to that partice will remain exactly the same. He also provided us with precise rules for translating positions and sizes and velocities from one coordinate system to any another.

For Einstein there is no overarching space or time for the relative to fit in.

The relative is not a thing that literally fits into anything at all, so I presume you are using the term metaphorically, but I'm not clear how I should understand the metaphor. Nevertheless, be clear about this: for Einstein there is precisely one spacetime, so if by "there is no overarching space time" you mean to say that for Einstein there were many spacetimes, you are just plain wrong. What there is not, for Einstein, is a preferred coordinate system for describing locations of the things that populate the one and only spacetime.

Of course, all the non Euclidian spaces are mathematical constructions that can be thought, but cannot be perceived. Kant really only talks about our experience of space, and so long as no-one experiences a four-dimensional space, that still holds. — Echarmion

Thank you for saying simply and clearly what I have tried to express on numerous occasions but could't figure out how to say it.

if only to save the scientific reputation of Einstein.

That's a bit pompous on my part. Einstein's scientific reputation does not need saving by me.

Of course, all the non Euclidian spaces are mathematical constructions that can be thought, but cannot be perceived. Kant really only talks about our experience of space, and so long as no-one experiences a four-dimensional space, that still holds.

Actually, I wouldn't mind pursuing this a little further, i.e. Einstein versus Kant, it might help me get clearer on Kant.
As I understood Kant, we don't experience space at all, it is instead the framework that outer experience has to conform to. If that is right even three dimensional space cannot be perceived. Given that he did most of his serious work before Gauss and Reimmann were even born, the only model of geometry he had available to him would have been Euclid's. So, it is not surprising that where he does talk about geometry it is of the three dimensional kind. Would it really have made a difference to him had he been aware of the possibility of coherent geometries with more than three dimensions?

I shall immediately raise my horn to Roland! In this case Mww. @Mww Come, and if we need help, help us!

It seems to me he did discuss a ship moving, and how it changed in perception, and what we do to make sense of those apparent changes. And it also seems to me you know more than you think you do. As I understand him, his project was to account for scientific knowledge, practical knowledge (I'm taking these terms in their simple and un-mysterious sense) being something different. And his scientific material was mainly from perception and reason applied to things perceived.

As to matters of science about things that are not perceived, e.g., QM, I reckon he might have made a separate category, but that it would not have slowed him down much. Caveat: beware claims about "understanding" Kant.. .

Thank you for saying simply and clearly what I have tried to express on numerous occasions but could't figure out how to say it. — tim wood

Thanks.

As I understood Kant, we don't experience space at all, it is instead the framework that outer experience has to conform to. If that is right even three dimensional space cannot be perceived. — jkg20

I guess you could make a technical argument here about how the form of the experience is part of the experience, but I think it doesn't really matter.

Given that he did most of his serious work before Gauss and Reimmann were even born, the only model of geometry he had available to him would have been Euclid's. So, it is not surprising that where he does talk about geometry it is of the three dimensional kind. Would it really have made a difference to him had he been aware of the possibility of coherent geometries with more than three dimensions? — jkg20

It's not an easy question to answer. I think the rub is that Kant says that all experience of external objects is formed by space and time. So, one might argue, there ought not to be a theory, based on experience, that space is not, after all, three dimensional. If the form is inherent in all experience, how can experience then establish something beyond the form?

I am not sure if Kant would have been concerned either way. That whole section of the critique has two purposes: To demonstrate that experience is formed by the mind, and that these forms allow synthetic a-priori judgements. Neither point seems to me particularly impacted by choosing the wrong number of dimensions.

Going back to my earlier point, Kant examined with great care what time and space "are like from the inside", and what we can conclude from that. And that critique still seems very relevant, even if it turns out our experience isn't even a good approximation of physics.

beware claims about "understanding" Kant — tim wood

In a way, I find Kant easy to understand in broad strokes, because it's all so well thought out. Actually following all these individual thoughts is quite another matter.

The way time is treated in Kant is something a person is experiencing in the context of being a person experiencing things. Einstein is claiming that our experience of time is exactly not the way to go about understanding what it might be.

So, how do those two completely separated ways to think about it meet? Maybe they don't.

Hey.....

A couple of cents.....

....Kant knew of spherical geometry, and qualified all his analogous geometric figures with “...straight lines..”. All he was doing is proving, within the context of his own theory, the possibility of synthetic a priori cognitions. He didn’t need to complicate the issue, because whether planar or spherical, the a priori relationships contained in one are just as a priori, and just as synthetic, as in the other;

..... we do not experience space and time, the reasons for that, and what experience actually is, is given further along in the text. Space and time are merely the necessary conditions for possible experience. Possible because space and time are themselves alone insufficient for experience, but are absolutely the ground for what may become experience, all else being given;

.....Einstein didn’t have much use for Kant, re: “Geometry and Experience”, 1921:

“...Is human reason, then, without experience, merely by taking thought, able to fathom the properties of real things? In my opinion the answer to this question is, briefly, this: as far as the propositions of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality...".

This is a rather ill-disguised denunciation of those very synthetic a priori cognitions Kant derived in the Transcendental Aesthetic, CPR, 1787.

Still, I have always wondered, given this:

“....If, for example, I consider a leaden ball, which lies upon a cushion and makes a hollow in it, as a cause, then it is simultaneous with the effect...” CPR A203/B248

.....did Einstein get the idea to bend spacetime by merely extending the notion of a bent cushion? Same principle, right? I don’t think Einstein used the colloquialism “fabric of space” himself, that being reserved for “GR For Dummies” and such pop-science, but he did envision it being deformed by massive objects. And he was quite familiar with Kantian physics and philosophy. Sooooo.......

Anyway, Kant concerned himself with the affects of objects on us without regard for relativity, Einstein concerned himself with the affect of objects on space or on time because of relativity. Both paradigm-shifting thinkers; just different paradigms, the former subjective, the latter objective.

Cheers.

:up:

(And objective denotes subjectivity-invariant.)

There's a reason they don't teach Kant in physics classes.

As far as I can see, Einstein sees me as 5" 2 in height relative to my perspective. With different speeds people could truly say I was a different size. Kant however. would say those are psychological experiences inbetween our innate sense of objective space and the noumema of my body. So there is an objective frame of reference and everything relative has to do either with things shirking or expanding, or us experiencing them distorted

I think that the universe truly has an objective "look", If only we had the right eyes to see it

Hegel thought we create the world thru syllogisms of the Spirit. A bit far for me

I do believe we can experience all truth in this life

I would tend to agree. The time it takes for you to fly to the moon and back for me is whatever the time of it is; the time it takes for you to fly to the moon and back for you is whatever the time of it is. Whether or not the times are the same or not has nothing to do with our respective internal sense of it, and why the times should be different under certain conditions has just as little to do with us as mere observers.

Sure as hell wasn’t my fault I got older and you didn’t. Although, I gotta say....it’s funnier that you shrunk and I didn’t.

No doubt. :smirk: