The h Bar

Relativisticcucumber

03:44

@ACuriousMind So, here, he is talking about the group that the Lorentz transformations make up, and he says that, initially, when we have that O(3) is the group of matrices that satisfy $R^TR = 1$ where 1 is the identity. then, he says "sometimes we choose to exclude parity transformations by demanding that the matrices have unit determinant, and this leaves us with SO(3)." [...]

[...] so then he says when we go to lorentzian group, we make this requirement into $R^TT = \eta$ and that this group then becomes O(3,1). Then, he says the quote i mentioned above. [...]

[...] and i have read that the universe does not exhibit symmetry under time translation or parity translation, so i suppose this is why we need to eliminate them, but i find it strange that they are solutions to begin with. and they are physically realizable solutions, yet we eliminate them? and i still dont see why there is only a discrete time reversal [...]

Silly Goose

04:10

So I was told that in Quantum, we have our nice and fancy Lie group. At the identity, we have our tangent algebra or our Lie algebra. This Lie algebra together with the all mighty exponential map (usually) allows us to generate every element of the Lie group.

In GR it seems like we want to access the tangent space at every point on a manifold whereas in Quantum, we do not care so much about the tangent algebra at every point on our manifold (Lie group). Why? Are manifolds in GR not so nice as the manifolds in Quantum?

[1] The usually parenthetical: When we cannot generate every element of the Lie group with elements of the Lie algebra, is that when we have to compose two exponentials of hermitian operators: one that lives in the Lie algebra, and another that lives in some other tangent algebra?

or I guess maybe the quantum blurb is only applicable to SU(2).

nickbros123

04:46

In books like kleppner and kolenkow, when talking about gyroscopes, and spinning cigars, why do they imply that a change in direction of the angular momentum vector (or a component of it) results in a change in orientation of the axis of rotation.but isn't this non trivial? Shouldn't the angular velocity not necessarily depend on angular momentum?

Mr. Feynman

@Relativisticcucumber No, that's not why we eliminate them. Although it's true that not all phenomena are parity preserving (weak interaction), the reason why we do that is mathematical. Those group you mentioned are not connected. Only the part of the group that is connected to the identity element is related to the Lie algebra, more precisely the exponential map takes the algebra into this part of the group

So we construct all the representation theory of such groups considering the connected component of the identity element i.e. $\mathrm{SO}(3)$ for $\mathrm{O}(3)$ and $\mathrm{SO}^+(1,3)$ for $\mathrm{O}(1,3)$

Relativisticcucumber

@Mr.Feynman can you elaborate on this "Only the part of the group that is connected to the identity element is related to the Lie algebra"

Mr. Feynman

Have you heard of the exponential map?

That's also what you consider in QM in most cases, the connected component of the identity element is really made up of those you call "infinitesimal transformations" (or rather, by composition of those :P)

In simpler words, it means there is a continuous path connecting every transformation to the identity, think of a $\mathrm{SO}(2)$ matrix for example: $\begin{pmatrix}\cos\theta&-\sin\theta\\ \cos\theta & \sin\theta\end{pmatrix}$. You can smoothly change $\theta$ to $\theta_F=0$ to make it the identity matrix, that is the whole group is the connected component of the identity and thus is connected

On the other hand, if you think of $\mathrm{O}(3)$, a parity transformation is represented by $\mathrm{diag}(-1,-1,-1)$ and there is no way to construct a continuous curve connecting it to the identity matrix

Anyways, once you know how to represent the connected component of the group, representing also parity is not a big deal. It's basically about multiplying by the above $\mathrm{diag}(-1,-1,-1)$ matrix above

@Relativisticcucumber Now I'm late for the bus so I'm leaving and I'll read the chat later, please tag me in case you reply otherwise I won't see the message.

Relativisticcucumber

05:41

@Mr.Feynman i am looking into it now, but i have not before

@Mr.Feynman okay i get what you are saying about what it means that these do not smoothly connect to the identity. however, i am not sure why we have that requirement? i guess this is what you mean by "Only the part of the group that is connected to the identity element is related to the Lie algebra", but i do not see the physical meaning of this in this case?

by the way thank you for your response

Mr. Feynman

06:09

@Relativisticcucumber It's Math, it is not Physics at this point. The point is that the Lie algebra is the tangent space at the identity, so it "approximates" things close to the identity, that is locally

Different groups can have (up to isomorphisms) the same tangent space at the identity. That doesn't mean in general that the groups are the same globally, but only locally. The Lie algebra doesn't catch (through the exp map) the whole group in general

Slereah

07:46

It's like integrals being the same up to a constant

user36093

07:56

@John Rennie Following on from our discussion the other day how would you write an equation that relates change in acceleration for some small change in tau (if the change of position is very nearly zero) I tried to do it with g=(G m1 m2/r^2)-(G m1 m2'/r^2) =G m1 m2'/r^2 but for higher values of m2' g is smaller which is clearly wrong.

John Rennie

Typically we look at the situation where the falling object is initially at rest. In that case the only non-zero component of the four-velocity is uᵗ.

The expression for the acceleration then simplifies to:
$$\frac{d^2x^\alpha}{d\tau^2} = \Gamma^\alpha{}_{tt} u^t u^t $$
OK so far?

user36093

no sorry I dont understand your way of expresing it

what is the $$ signify

Oh just the ends of the expression?

John Rennie

Ah, I used MathJax to write the equation. t should appear like this:

You'll need to install an addon to make MathJax work in the chat. Let me see if I can find the link ...

39

A: Any chance of MathJax in chat?

As a workaround while this request is pending, there exist several client-side workarounds that can be used to enable LaTeX rendering in chat, including: ChatJax, a set of bookmarklets by robjohn to enable dynamic MathJax support in chat. Commonly used in the Mathematics chat room. An alternat...

Silly Goose

i will forevermore think of fibers when i see integrals up to a constant (that then differentiate to the same derivative)

user36093

should I be able to reply in that new window you created?

John Rennie

08:11

Just reply here

user36093

ok yes pleas go ahead

Silly Goose

wow I've just installed chatjax and how nice it is. Here's a celebratory $\mathcal{H}$

John Rennie

To get any further we need to know what the Christoffel symbols are, and they are tedious to calculate so we usually use a tool like Mathematica to calculate them or just look them up.

I have done the calculation somewhere on the SE. If you give me a moment I'll look for it.

user36093

righto

John Rennie

Found it! It's this answer:

41

A: How does "curved space" explain gravitational attraction?

If you have a look at my answer to When objects fall along geodesic paths of curved space-time, why is there no force acting on them? this explains how on a curved surface two moving observers will appear to exprience a force pulling them together. However two stationary observers will feel no fo...

Have a read through that and see what you think.

user36093

08:19

ok thanks ps my message on fb the received tick is grey , apparently indicates you are not signed in. :-)

Silly Goose

@JohnRennie I've found the issue with my mathcals showing up as boxes business :). It turns out to be caused by me updating my MacOS. I found out a fix courtesy of this post: meta.stackexchange.com/questions/384924/…

John Rennie

@SillyGoose Aha :-)

Relativisticcucumber

@Mr.Feynman okay so is it like if we apply these transformations many times it should amount to doing nothing and should smoothly connect to the identity and we only want to consider the transformations that achieve this? sorry if im still missing smth

@SillyGoose what does this mean

Silly Goose

wait what does what mean ! @Relativisticcucumber

Relativisticcucumber

@SillyGoose wow can u help me install it

@SillyGoose this!

"i will forevermore think of fibers when i see integrals up to a constant (that then differentiate to the same derivative)"

Silly Goose

08:26

Let's say you have a map $\varphi: G \rightarrow H$. Then, let $h \in H$. The fiber of $h$ is the set $\{g \in G: \varphi(g) = h\}$.

To get ChatJax, go to this page: math.ucla.edu/~robjohn/math/mathjax.html, and then book mark the "start ChatJax" and "render Chatjax". (like literally put the links in your bookmarks bar). And then come back to hbar and click "start ChatJax" from your bookmark bar and then be ready to have your pantst blown off by all the rendered latex

so the fiber of an element that lives in the codomain of some mapping is the set of all elements in the domain that collapse to said element in the codomain when sent through the map

Relativisticcucumber

@SillyGoose gotcha

Silly Goose

so in the context of integration/differentiation, the fiber of the function $f(x) = x$ could be $\{x^2/2 + C : C \in \mathbb{R}\}$ (if we sent this function through a differentiation map, I guess if that exists)

The concept of fibers comes up in group theory because fibers of homomorphisms are one way of defining elements of quotient groups I think

Relativisticcucumber

@SillyGoose I GOT IT WOW

@SillyGoose yeah yeah i see where ur going

Silly Goose

the kernal of a homomorphism is a particular fiber as well :) all elements of the domain that collapse to the identity of the codomain :D

Relativisticcucumber

kernal

Silly Goose

08:33

pop

did you get chatjax :D @Relativisticcucumber

Relativisticcucumber

wait do you follow the replies to their original message

Silly Goose

OH

I see

Relativisticcucumber

LOL

Silly Goose

these notes follow dummit and foote it looks like pretty much exactly and are just more concise for the definition of fiber, how they build quotient groups, and then why elements of a quotient group can also be thought of as cosets: people.math.harvard.edu/~bullery/math122/…

Relativisticcucumber

nobody:

absolutely nobody:

Silly Goose

08:38

LOL

Relativisticcucumber

silly goose: here is an infinite amount of abstract alg info

Silly Goose

now is it countably or uncountably infinite?

now we add analysis to the mix ;)

Relativisticcucumber

unctbly

Silly Goose

can you tell me the bijection into the reals please and thank you

Relativisticcucumber

my supervisor is asking me to get to work sorry toodaloo

Silly Goose

08:41

tood a loo! @Relativisticcucumber

nobody:

undergraduate ENM: how well do you know geometry?

ACuriousMind

@Relativisticcucumber Why do you find it strange? I mean, there is no physical reason every random transformation that preserves the metric needs to be a symmetry of our full theory in the end

Relativisticcucumber

@ACuriousMind i guess i thought this is the definition of a symmetry

ACuriousMind

Physically, I think about this like this: The transformations continuously connected to the identity are those that are "realizable" - all the physical processes I know of are continuous, so I can see the physical realizability of a boost to velocity $v$ as first accelerating to velocity $\epsilon$, then to velocity $2\epsilon$ etc. until I arrive at velocity $v$

similarly for rotations - when there is an infinitesimal version of a transformation, then I can see how to "implement" it by repeating small steps, ultimately having a continuous process

but the discrete transformations like time-reversal or parity aren't like that - you either do them or your don't, you can't do a time reversal "halfway"

and so they aren't as "physical" as the continuous transformations: you can use them in the math but you can't implement them via a process

@Relativisticcucumber A symmetry of a theory is something that leaves my action invariant, no?

The very general idea of a physical theory doesn't even know what a metric is

the reason we care about the metric is that it turns out that since this metric seems to be what is realized on our spacetime, it is much more convenient for us to construct theories that are covariant/invariant w.r.t the isometry transformations of that metric

in principle you can write down any theory that breaks Lorentz symmetry that you want :P

Silly Goose

09:01

i thought kant was the popularizer of the idea that human knowledge is limited. and i always assumed that acknowledging human knowledge to be limited necessitates there being no objective truth or at least an objective truth that can be meaningfully understood. but it seems this is not the case? kant believed in an objective truth (noumena), right?

the starred message of nigel made me think of this earlier :P

Relativisticcucumber

so the thing i am confused about is i was kind of (i think) taught this idea by looking at a shape -- maybe a triangle or a sphere, and the group is the elements that are a symmetry, and by this i refer to things that, when done, you have the identical thing that you started with (circle, triangle, etc.) so i see that in this context we are looking for things that leave the physics the same, and we are looking for ways to transform the coordinates to achieve this [...]

[...] but im confused about how we are doing anything that considers the action? because this section of the book just says we want things that satisfy this relation that $R^TR= \eta$

so bleh i think im still missing something here

@ACuriousMind the above messages are in response to this

ACuriousMind

@SillyGoose well...Kant "believed" in noumena but he didn't think they were knowable

Silly Goose

what is the rationale for believing in the existence of something that can never be known (well I suppose this may be asking you to distill a sizable chunk of quite a text) :P

ACuriousMind

One aspect of the "I had to get rid of knowledge to make room for faith" I alluded to somewhere else in that conversation is that precisely because we cannot know things-in-themselves (noumena) we are free to believe in humanity as a thing-in-itself

Silly Goose

hmm

@Relativisticcucumber want to read the critique of pure reason ;)

some may say you make a critique of pure reason every day

Relativisticcucumber

09:07

@SillyGoose i dont feel the need to read kant

ACuriousMind

@SillyGoose I don't think it matters very much to Kant whether or not you really believe that noumena "exist". What matters is that you understand the concept of things-in-themselves and can therefore understand the formulation of the categorical imperative saying we must not treat humanity as a means to an end, but as an end-in-itself

Silly Goose

so kant wants to say noumena exists emphatically for the sake of saying that it cannot be known?

ACuriousMind

yes

very Socratic: The concept of the noumena is necessary so that we can know that we don't - and cannot - know everything

Silly Goose

maybe i shall try another swipe at kant soon :P i feel some education in physics and math may have helped improve my ability to read philosophy. i remember not being able to read some of a wittgenstein or something because it had a brief blurb about "going beyond Euclidean geometry" which I did not know what Euclidean geometry was and how one could go beyond it XD but stuck no longer I'd be on such a passage

ACuriousMind

I'm not sure I'd really recommend Kant to get into philosophy

pretty notorious for being hard to read, although I don't know how the English translations are

Slereah

09:29

More like Emmanuel Can't

My advice is to not read any historical philosophers

Being first at a particular idea does not mean being the most pedagogical to write about it

just read an intro to whatever topic you wish to know about

This isn't the 12th century, we don't have to read the same 3 books of Aristotle for the rest of our lives

Silly Goose

how well established are interpretations of these source materials? Say the critique of pure reason. though, it doesn't really seem like you can win: you read secondary material and get someone else's idea of what is said which is wrong, or you read the primary material and understand nothing at all!

Slereah

I just use my pure reason to understand it

Silly Goose

:)

you use your pure reason to make your own critique of pure reason

Slereah

Kant thought Euclidian geometry was Fundamental so I wouldn't trust him tbh

Silly Goose

is that what he means by space?

ACuriousMind

10:20

@SillyGoose I think a mix - as you do in an actual philosophy class - is best: Read the original (not all at once, in chapters or whatever), then read selected commentary on what you just read.

Mr. Feynman

11:14

@Relativisticcucumber why doing nothing?

Amit

11:49

Is there any advantage of ChatJax over the scripts? I was so glad finding out there's a way to render MathJax without having to install anything...

Mr. Feynman

@Amit You can put it in the "favorite" bar and render MathJax with a single click. I don't know what the scripts do but chatjax is really just this

Amit

Yes, that's what I mean, and that's what I'm doing :)

Got it from here: math.ucla.edu/~robjohn/math/mathjax.html

Ah I see -- ChatJax is also script based. I must have confused it with some browser extension

ACuriousMind

...what do you mean by "ChatJax"

there are several different things that are called that :P

user2236

re: ⭐ link

ACuriousMind

12:07

@Amit 3 of the 4 options in the meta answer linked in the room description are called "ChatJax"

they're all "scripts", but for some of them you need one of the scriptmonkey extensions to run them

Amit

Ah I see

Ryder Rude

12:27

Hi

Amit

Hi rider dude

Ryder Rude

@ACuriousMind How does Kant justify that sentience is inseparable from the notion of collections (i.e. the ability to recognise multiple different things)

ACuriousMind

what

Ryder Rude

Kant says collections are intrinsic

ACuriousMind

Kant never uses the word "collections" to the best of my knowledge

Ryder Rude

12:30

Oh. So he just says "reasoning" or "logic" is intrinsic

ACuriousMind

he says the category of quantity - notions of one, many, whole - is an a priori part of reason

Ryder Rude

Yeah, thats wut im saying. He says reason is intrinsic. And reason, by definition, must have collections

How does he justify that reason is intrinsic

ACuriousMind

what

Ryder Rude

intrinsic to conscioisnes/sentience

He does say reason is intrinsic and not learned, right?

Like sentience comes for free with reason

Sorry reason comes for free with sentience

As if they're inseparable. Maybe the same thing

And by extension, this also makes collections inseparable from these two.. Becuz collections r inseparable from reason

I have formed an opinion that is more like : a primitive form of sentience may neither recognise reason nor collections. It may only recognise qualia @ACuriousMind @Amit @Slereah

But Kant is saying that reason is instrinsic. Wut is his motivation

My notion of primitive sentience only recognises qualia and the fact that it itself is sentient

Slereah

do u not have a qualia of quantity

ACuriousMind

12:37

@RyderRude ehhhhhh

Slereah

When you see two objects do you not have an intuitive understanding that it is more than one

Amit

Recognize Qualia? That means recognize its own Qualia? Otherwise I don't see how

user2236

Definition of "reason" please.

Ryder Rude

@Slereah i mean an extremely basic form of qualia. It barely recognises that it itself is sentient. Think of a blind man

Slereah

How do you know which qualia is basic

Ryder Rude

12:39

A blind man def does not see anything, not even black. Now think of a blind man and strip him of every other qualia except the recognition that he himself is sentient @Amit @Slereah

Slereah

its the floating man

Floating man

Floating man is the proper translation of the verb "yahwā in al-Nafs," which means "to fall down." Flying man is another term used cohesively to describe a floating man. According to Ibn Sina, it is considered a thought experiment to determine if the soul exists or not. This is an argument to determine if there is consciousness. == Background == It has been said that Ibn Sina wrote the argument while imprisoned in the castle of Fardajan in the Iranian province of Hamadan. He concluded that the soul is immaterial and substantial. He also claimed that all humans could not deny their consciousness...

Ryder Rude

@Slereah The person im talking about only exists but does not have any thoughts and sensory inputs

@Slereah this is great thanks!

ACuriousMind

@RyderRude I think you're really too quick to try and summarize rather complex positions in a few words

Slereah

shit is literally one thousand years old

Ryder Rude

Yeah, philosophy is extremely subtle :P @ACuriousMind

Slereah

12:41

Need to brush up on the classics mb

ACuriousMind

here's a summary of how consciousness and mind fit into Kant's (meta)physics - it's pretty long and I don't know I could make it shorter

Amit

This kind of investigation is what I believe seduces people to go into psychedelic drugs experimentation. To find some sort of proto sentience or something. It's not a criticism just an observation

Slereah

@Amit let's get @RyderRude fucked up

Amit

😂😂😂

Ryder Rude

@ACuriousMind thanks. I will try to read it

@Amit I think they're a great thing

Amit

12:44

From experience?

Ryder Rude

I've only had LSD

user2236

Is there any difference between reasoning and inferencing in Kant's view.

Ryder Rude

But i will try DMT someday

Has anyone had DMT

Amit

It's not an only imo

I don't wanna experiment this way personally

user2236

Some philosophers make a big deal about it.

Amit

12:46

Risk reward thing

Ryder Rude

They're not addictive @Amit

They're different from opiates

And have many medical uses

Amit

In ancient times there's a case to be made that the only real knowledge is "via ecstacy"

Slereah

all the cool scientists took drugs

u should do it

Amit

I mean that it was the world view

Ryder Rude

Opiates are what are a risk/reward thing

ACuriousMind

12:48

@Slereah is that statistically significant or were the uncool ones also doing drugs but we never hear about it :P

Slereah

You never hear about an Erdos number for people who don't take amphetamines

Ryder Rude

That's becuz they were doing opiates

Amit

@RyderRude It's not so simple. People often say you need to investigate this stuff well before trying, but they often fail to mention you also need to investigate yourself quite a bit because at the end its an interaction between you and a substance that matters

Slereah

Erdos is a bit unjustly maligned tho

He took like 20mg a day IIRC which is basically therapeutic doses

ACuriousMind

the original microdoser

Ryder Rude

12:50

@Amit opiates r beyond ur control. I cant think of anyone who didnt try them twice

Slereah

"The simplest explanation of the difference between meth users and responsible amphetamine users is that the meth users take much, much more. This study asks abusers how much they use in an average day, and gets numbers from about 300 to 800 mg. An average clinical dose of either Adderall or Desoxyn would be about 20 mg a day."

user2236

Did Kant take drugs

Amit

@RyderRude That may be true, I still say that for certain people other stuff can be even worse

It's not just about the addiction

Slereah

Hallucinogenics were pretty rare to come by in Europe before the 20th century from what I can tell

They became a bit of a trend in like the 1920's with mescaline

If you wanted hallucinogenics in Europe before then the choices were pretty dire

Mostly things which are basically poison

Like digitalis

or ergot

Ryder Rude

@Amit u can say the same about drinking or smoking

They r just socially acceptable /profitable

Amit

12:54

@RyderRude I can and I am! :)

Even caffeine

Ryder Rude

Oh :)

Slereah

Digitalis was apparently part of recipes for witches brew in like Renaissance era

Which I guess would make it pretty good if you want to see devils

user2236

Maxwell's demons

Amit

I'm a caffeine addict and even that bugs me often lol

ACuriousMind

Kant was an extremely boring person who never left the city he was born in, had a strictly planned routine and - of course - thought any use of drugs at all was bad because, as drugs alter our ability to reason, it did not respect reason as an end-in-itself

Slereah

12:56

nerd

Your average 16th century hallucinogen

Given the ingredient list you are probably gonna meet the devil if you take it

Ryder Rude

Heroin was apparently invented to get all the benefits of cocaine without the bad stuff

Slereah

I think you mean opium

Ryder Rude

Oh

Slereah

Heroin would do quite the opposite of cocaine

doing the classic mistake :

heroin addicts christmas

►

Ryder Rude

I mean the scientist who invented it thought that he was making a gigantic improvement over cocaine

Amit

13:01

Golden brown

Ryder Rude

But ofc, he invented something even worse

user2236

Coke is an upper, and heroin is a downer or pain killer.

Slereah

13:20

God's Own Prototype - _Too Weird To Live_ Too Rare To Die_ - Fear & Loathing In Las Vegas

►

Classic scene

user2236

The Hard Truth About Reading Math Books

►

Time, patience, and effort

Ryder Rude

Lucid dreaming is a good substitute for drugs @Amit

No side effects, cuz its just a body function

But its not a super happy feeling either

And its not abstract either

Its just like real world with cheat codes

The only happiness i feel in them is the excitement of having cheat codes

So its not some drug induced happiness

But i guess opiate induced happiness must come with extreme sadness too

Maybe opiates are like u borrow happiness and u have to give it back with interest

But ive never done it, so idk

Slereah

13:37

No time like the present

Ryder Rude

@Slereah Have u ever managed to astral project

I have lucid dreams but cant astral project

Slereah

I'm doing it rn

It's full of ghosts

Ryder Rude

U gotta guard ur body then :P

Amit

Lol

Consciousness is always affected by drugs anyway, it's just that some people like to disturb the natural drug balance

Slereah

If you want to experience it without drugs you can just get schizophrenia

Ryder Rude

13:46

Yeah, our brains did not evolve for overwhelming happiness

Meth damages the happiness receptors

I guess it makes sense. The parts of the brain that control happiness can break when overwhelmed with happiness

This is y there can b no good opiate

But im no neuroscientist. Just take it as speculation

Amit

These guys who do remote viewing should find a way to improve astronomical observations

Ryder Rude

I believe every person starts off as a floating man when they're a fetus

But i also believe collections dont exist in nature. So Im interested in how the floating man slowly develops a notion of multiple things

But this is very weird. How can u get multiple things if u dont assume multiple things. No one has defined collections using something more basic

Collections r def present in qualia. Cuz u have a notion of different colors and different sounds

Amit

14:03

It's all a psychedelic exaggeration of natural survival abilities, the human consciousness :p

We are confused about why animals are so different than us 'cause we live on a trip

Ryder Rude

But this assumes collections r out there. And consciousness is an illusion.. This is closer to computationalism

ACuriousMind

@RyderRude careful: I think you've started using the word "qualia" ever since I used it to refer to sensations in general

Ryder Rude

I believe something objective is out there, but its unknowable. And its nature is not collections

Amit

Why do you need to know what's out there what will you gain?

Ryder Rude

@ACuriousMind i use it to refer to the like the "picture" in the mind. The television

But i also use it for sounds

Amit

14:08

Is there a real interest or is it just a mental exercise?

ACuriousMind

that's not what the term is supposed to mean: A quale is specifically the aspect of conscious experience that is not part of what we can factually communicate when we talk about it: When I say "I see a red square", this is a description of my perception, but not of a quale. The quale is the incommunicable part of what "redness" means to me, what it feels like to see something that is both red and a square

Ryder Rude

@Amit i dont want to know that. I only want to know how collections can b derived from it

@Amit just entertainment :P

Amit

That's your answer there, collections are created for entertainment

Ryder Rude

@ACuriousMind Sorry, maybe i described it wrongly. I'm using it in exactly this sense. It's like that thought experiment where u tell a person all information about red, and qualia is what they can never infer from that

Slereah

I remember that there was an experiment involving switching the optics and auditory nerves of animals

ACuriousMind

14:11

Generally people would not say that the notion of quantity is a quale, precisely because we can formally reason about quantity. We can agree on what numbers are, and how to count with them, there's no incommunicable subjective part to this

Slereah

They were apparently doing fine at navigating the world

Ryder Rude

So they start seeing air pressure?

Slereah

But did they have the same qualia???

Who knows

user2236

How can you communicate the incommunicable?

Slereah

I don't think it has been attempted with humans

@user2236 I believe that question was approached here

The Simpsons - My Dinner With Andre

►

user2236

14:13

hmmm

Slereah

Wittgenstein would ask if you can communicate anything

user2236

"what it means and feels like to me" is as individual as it gets

ACuriousMind

@Slereah Whereof one cannot speak, thereof one must be silent.

user2236

We can never speak of what another feels.

::eternal silence::

Ryder Rude

@ACuriousMind I believe collections have to be ultimately subsumed in qualia. Becuz we know of multiple only becuz we can perceive multiple things : we have distinguishable qualia. But ofc the qualia themselves r indescribable

How do u know two chairs exist? It's becuz there is the concept of distinguishability in the picture formed in ur head

ACuriousMind

14:24

@RyderRude I still think you're using the term "qualia" too broadly.

For quantity, there is no subjectivity as there is e.g. for the perception of color: No one asks "Is your 2 the same as my 2?"

Ryder Rude

yeah. Sorry... i had forgotten about this argument

ACuriousMind

I don't see an incommunicable part to the experience of "there are two distinct chairs" in the way there is an incommunicable part to "the chair is red"

Slereah

Are u sure

ACuriousMind

@Slereah never!

Slereah

What if the word "two" that you have been trying to understand your whole life is wrong

you just saw examples of what twoness is

Amit

14:27

Consider synesthesia

Slereah

but maybe you just got it wrong!

user2236

is it sort of like: you don't know my pain because it is not your pain

Ryder Rude

@ACuriousMind but ultimately 2 cant be defined. What u mean by 2 is just a concept of two distinguishable things in the picture u form

So i think people agree about 2 in the same way they agree about qualia

Neither can really be defined

We just agree that our perceptions are alike

Slereah

picturing Socrates going around asking people what two means

ACuriousMind

@RyderRude but the notion of distinguishability is communicable, even if two people might not always agree where a line of separation between one thing and another is to be drawn

Amit

14:28

Why do we need to be certain that we have a shared experience of some sort is interesting

The fact that we pose such a question implies something

ACuriousMind

We can argue over whether or not some sort of folding chair that can be taken apart into two components is really "one thing" or "two things" and that might reveal interesting differences in what we consider to be "a thing", but there's a discussion here

I cannot discuss with you about how I perceive the color red

It is impossible for me to delineate the perception of red against e.g. the perception of blue in any way that would make it easier for you to understand where I see the difference

(I'm somewhat color-blind and do have first-hand experience of the impossibility of trying to communicate unusual color experiences to other people :P)

user2236

Me too.

Words aren't enough.

Ryder Rude

I agree that what qualia are is incommunicable. But qualia have one property that is communicable : distinguishability. Like u can communicate to a person that, in ur perception, u can feel distinguishable things... without being able to tell them what ur perceptions are actually like

So in this sense, collections arise from a property of qualia thay is communicable

Slereah

Ah, the socratic method

Ryder Rude

Maybe im using qualia in a broad sense. Im just saying that u can communicate that ur perceptions have a distinguishability property

user2236

14:35

But then you're just using synonyms ...

Amit

Misuse of a survival mechanism

Ryder Rude

Becuz everything that we know is through perceptions,.... collections must also originate in our perceptions

user2236

the perception that you experience cannot be experienced by me

ACuriousMind

@RyderRude now that's very close to what Hume says and his distinction between impressions and ideas: From the memory of a lot of impressions, we ultimately form an idea about some of these impressions referring to the same thing and some of these impressions referring to another.

user2236

> the memory of a lot of impressions

ACuriousMind

14:41

It is crucially not what Kant thinks: Kant believes in "synthetic judgements a priori" - ideas, genuine conclusions we can arrive at that have no relation to experience whatsoever, amd mathematics is counted among those

In the end I think, though, you're asking a different question from what any of these philosophers are talking about: You seem focused on the point that there "is" something like quantity, and you want to know where it comes from

but...what does it mean for there to "be" the notion of quantity or a collection of different objects

it's not a thing that exists, it's a principle our minds use to organize

Slereah

But do principles exist 🤔

Ryder Rude

Do u mean that no precise boundaries can be drawn to define : 1 thing, 1 more thing, etc?

ACuriousMind

Even to Hume, there are inexplicable "principles of association" that describe how our minds form new impressions and ideas from old ones, and one of these is resemblance - this impression is like this one, but not this other one

@RyderRude I mean that separating our mess of perceptions into distinguishable objects is a process

user2236

Something that has "no relation to experience" can not be put into words

Slereah

I think the simplest solution is to go with Parmenides and deny that multiplicities exist

ACuriousMind

14:47

when we speak of distinct things, or of collections of perceptions or whatever, that's our minds organizing things

user2236

Words organize our thoughts.

ACuriousMind

As a silly analogy, programming is an act of translating mental concepts into code that sometimes bears some relation to the mental concept. Does that mean programming "exists"?

What would it mean to say it doesn't "exist"?

Ryder Rude

This is very weird. We're reaching the limits of language.. I don't even know how to object to that

Slereah

That's what you get once you start philosophizing too long

user2236

I haven't thought of that yet: because I don't know the words for it.

Slereah

14:50

that's why worrying too much about metaphysics always ends up in the same spot :p

ACuriousMind

perhaps even sillier: Does "getting out of the bed in the morning" exist?

Slereah

Typical Munchausen trilemma

@ACuriousMind Depends on your view on Leibniz

user2236

36 mins ago, by Slereah

Wittgenstein would ask if you can communicate anything

Slereah

Are we in the best possible world?

ACuriousMind

to me, these questions are about as meaningful as asking whether collections "exist". Organizing perceptions into mental bins, into notions of distinguishable objects, is something my mind does, not something that "exists"

@Slereah in the best of all possible worlds, "getting out of bed in the morning" would not exist

I could sleep all day

Ryder Rude

14:52

@ACuriousMind But there need be no bins or clear boundaries. All we need to agree on is that blue is dinstinguishable from red

ACuriousMind

So?

Slereah

but then you'll have to figure out if you're a man dreaming he is a butterfly or a butterfly dreaming that he is a man

Ryder Rude

I think distinguishability is intrinsic to our perceptions @ACuriousMind

ACuriousMind

mental categories are arbitrary

I already told you once that an elementary exercise in philosophy classes is to get students to define what a chair is

they invariably fail

clear-cut definitions are hard, yo

more news at 11

Ryder Rude

Yeah, but categories need not be defined. Im only saying that everyone agrees that two distinguishable colors exist

Slereah

14:54

user2236

dictionaries exist for a reason bro

ACuriousMind

@RyderRude so?

Ryder Rude

Bins come later. Names of colors come later. But distinguishability is fundamental @ACuriousMind

Labels can come later

user2236

look up "red" and move on

Slereah

my advice :

GET OUT OF YOUR HEAD

►

ACuriousMind

14:55

@RyderRude But the most elementary categorizing system is to take one thing and sort everything into "is like this" or "is not like this"

Ryder Rude

U r right. I just formed a category...

This is a very deeeep discussion

If distinguishable things dont exist intrinsically in our perception, how can our mind ever create distinguishable things out of them

ACuriousMind

you keep using that word "exist"

I still don't know what it means

user2236

Fermat's Last Tango (with subtitles)

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Ryder Rude

If one says that the mind is organising parts of our perception, we r already assuming "parts" Of our perception

Emilio Pisanty

physics.stackexchange.com/questions/757618/…

Can a mood point OP to math.se?

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