Is philosophical Skepticism true?

[Mach]

Possible? Sure. Likely? No. But it's also possible that we're all brains in jars or living in the Matrix.

Evidence to make the claim that you know it's possible?
True claims about reality originate from observation ultimately. If you have no such evidence, it's an imaginary concept.

No and neither can you.

So certain, despite claiming uncertainty. Resolve your contradiction.

 

[Mr Person]

The position of philosophical skepticism is something like this:

We cannot know anything about reality with certainty.

Or wiki:
(It is generally agreed that knowledge requires justification. It is not enough to have a true belief: one must also have good reasons for that belief. )
Skeptics claim that it is not possible to have an adequate justification.

Do you think this is correct? Why?

Please note this is different than scientific skepticism. Scientific skepticism is questioning whether claims about reality are justified scientifically...they are testable, evidenced, observable, etc. Scientific skepticism is really just applied science...or scientific inquiry, being critical, etc. Or the general definition of skepticism that is "to question". None of these types of skepticism is being addressed.

Response: True but useless other than for approving of inquisitiveness in general.



Truth: The only evidence of an existing world outside your mind comes from the sense impressions generated by your sense organs (eyes, etc). In fact, the only evidence of the existence of your sense organs comes from those sense impressions. Everything about reality, including the existence of any reality outside your consciousness, is therefore uncertain.

Uselessness: No matter how hard you believe this - I challenge you - you cannot cause the evidence of an outside reality to disappear or prevent it from affecting you. Go believe it whilst sitting on a highway and see what happens...



In short, it's possible that all of reality can be in YOUR head, but even a complete belief in the possibility as truth would accomplish nothing. It is therefore useless.



Hence, apart from using philosophy as a way from studying the shape of thought and methods of argument, it is only useful to explore physical reality when consistent with proven laws of physics. Otherwise, it may shed light on aesthetics, ethics, and the wisdom of using a physically possible - though technologically impossible at the moment - creation such as a teleporter.*



See: the philosophy of personal identity, specifically, The Zombie Problem, The Teleporter Problem, and related thought problems with the use of a device that would deconstruct at one point and reconstruct another, all portions of a person that are objectively real/provable, down to the spin state of quarks, etc. (Query: intersection of the observation problem with deconstruction/reconstruction, with regard to quantum phenomenae)

 

[Nilly]

Science uses impossible where appropriate, and uncertainty where appropriate. The blanket opposition to all certainty is a contradiction that persists, despite this.
Maybe breaking it up logically into the three component positions:

1. we can be certain and uncertain <- justifiable, reasonable, science, etc.
2. we are always uncertain < - skepticism, self contradictory
3. we are always certain < - poor underused position of tyrants or cult leaders? !

I like the groups, I would say that it's very important to be very careful when differentiating between 1 & 2. I think your disagreement with Cephus is down to some conflation between the two of them, and you're actually in the same group.

I think in order to subscribe to statement 1, you have to tacitly acknowledge that 2 is also 100% true, we're just allowed to conveniently skip around it in order to be productive. The ability to come to some advanced conclusions about reality is often dependent on assuming other, more basic conclusions are 'true' (even if they're not). It would be impossible to devise some advanced mechanics phenomena without first assuming principles of classical mechanics were true (even though, technically, many aren't. they're just good approximations).

Finally, and I don't know if you wanted this thread to go in this direction but whatever, I would also say my frustration with 'agnostics', is that they are perfectly happy to live life by statement 1, and consider mundane events to be subject to statement 1, but when the topic of god comes up they switch to statement 2. That inconsistency is jarring. It's fairly trivial to show someone to be irrational if they were to subscribe to statement 2 for their every action or belief, but suddenly when gods come into the equation everything seems to change.

 

[Paleocon]

The position of philosophical skepticism is something like this:

We cannot know anything about reality with certainty.

Or wiki:
(It is generally agreed that knowledge requires justification. It is not enough to have a true belief: one must also have good reasons for that belief. )
Skeptics claim that it is not possible to have an adequate justification.

Do you think this is correct? Why?

Please note this is different than scientific skepticism. Scientific skepticism is questioning whether claims about reality are justified scientifically...they are testable, evidenced, observable, etc. Scientific skepticism is really just applied science...or scientific inquiry, being critical, etc. Or the general definition of skepticism that is "to question". None of these types of skepticism is being addressed.

It's not even wrong, it's incoherent and self-refuting.

If we can't know anything, then we can't know that "we can't know anything".

There is also that weird deal where observing an experiment actually changes the results so there's all kinds of things that can happen in the sciences.

That's somewhat misleading. Observing subatomic processes requires active interference. Knowledge of a particular experiment in an epistemic sense doesn't change the outcome.

 

[Nilly]

That's somewhat misleading. Observing subatomic processes requires active interference. Knowledge of a particular experiment in an epistemic sense doesn't change the outcome.

If you're familiar with the double slit experiment skip to like 3.00

 

[Paleocon]

If you're familiar with the double slit experiment skip to like 3.00

I'm familiar with the double slit experiment, and with quantum mechanics more broadly.

Your video is misleading. The method of observation involves actively affecting the particle. The consciousness of the observer doesn't affect anything. Indeed, the entire experiment is over and done with before any human actually sees the results.

 

[Nilly]

I'm familiar with the double slit experiment, and with quantum mechanics more broadly.

Your video is misleading. The method of observation involves actively affecting the particle. The consciousness of the observer doesn't affect anything. Indeed, the entire experiment is over and done with before any human actually sees the results.

So honestly the experiment kind of blows my mind and I don't know completely what to make of it. Yes you're right that the method of observation affects the particle. But that's not the point. The point is that the method of observation is precisely the same no matter which detector the entangled photon goes to (D1 or D3). However the measurement is always different at each of D1 or D3. The only difference between the two scenarios is our knowledge of the rest of the setup.

 

[Mach]

I think in order to subscribe to statement 1, you have to tacitly acknowledge that 2 is also 100% true, we're just allowed to conveniently skip around it in order to be productive. The ability to come to some advanced conclusions about reality is often dependent on assuming other, more basic conclusions are 'true' (even if they're not). It would be impossible to devise some advanced mechanics phenomena without first assuming principles of classical mechanics were true (even though, technically, many aren't. they're just good approximations).

I thought it was the reverse. You first must accept that you can discover reality, to reasonably make ANY AND ALL CLAIMS about reality. You can be wrong, but you may also be right...that's fundamental.
In contrast, #2 "we cant be certain" <_ can't be certain about that either... it's a non-position

Are you really uncertain that the word "THIS" is not "THIS"? I'm certain it is, I'm bewildered by people trying to claim perpetual motion is possible, etc. It's identical to me as faith-based claims.

Finally, and I don't know if you wanted this thread to go in this direction but whatever, I would also say my frustration with 'agnostics', is that they are perfectly happy to live life by statement 1, and consider mundane events to be subject to statement 1, but when the topic of god comes up they switch to statement 2. That inconsistency is jarring. It's fairly trivial to show someone to be irrational if they were to subscribe to statement 2 for their every action or belief, but suddenly when gods come into the equation everything seems to change.

Heck, people disagree with established science too, takes all kinds

 

[Paleocon]

So honestly the experiment kind of blows my mind and I don't know completely what to make of it. Yes you're right that the method of observation affects the particle. But that's not the point. The point is that the method of observation is precisely the same no matter which detector the entangled photon goes to (D1 or D3). However the measurement is always different at each of D1 or D3. The only difference between the two scenarios is our knowledge of the rest of the setup.

I'm not sure what you're trying to say. Of course the detector that the photon went to produces a different result than the one it didn't go to.

I suspect there may be a misunderstanding between us.

 

[Mach]

Truth: Everything about reality, including the existence of any reality outside your consciousness, is therefore uncertain.

Including the above, which you are uncertain about. But you seem to claim it's "Truth"? It cannot be both, I'll leave you to resolve that contradiction and explain which was correct (?)

In short, it's possible that all of reality can be in YOUR head, but even a complete belief in the possibility as truth would accomplish nothing. It is therefore useless.

You can't be certain of that, so why propose it?

I'm writing that "we can be certain and uncertain" is consistent with most everything we are likely to discuss (and the rest wll be consistent only after a lot of back and forth).
"we cannot be certain" is inconsistent WITH ITSELF (we are certain that we cannot be certain...contradiction)

It's a contradictory premise and should be discarded as useless up front. You at least agree its useless, just for a slightly different reason

 

[Mach]

It's not even wrong, it's incoherent and self-refuting.
If we can't know anything, then we can't know that "we can't know anything".

I agree.

That's somewhat misleading. Observing subatomic processes requires active interference. Knowledge of a particular experiment in an epistemic sense doesn't change the outcome.

I agree with that too. I actually brushed up on uncertainty just prior and was surprised it hadn't come up yet...but it has and I agree.

 

[Mach]

Coincidentally, this morning, my first post dealt with this in anther thread:]

It was no coincidence. <- I am certain of that. How do you like that? Don't bother telling me since you claim you can't be certain!

If you could use the OP language specifically and state your position, rather than your home-brew stuff, I'd have something more to respond to.

 

[Frank Apisa]

It was no coincidence. <- I am certain of that.

I'll accept that you are certain it was not a coincidence.

How do you like that?

Enough to say, "Thank you."

Don't bother telling me since you claim you can't be certain!

I did?

Where?

If you could use the OP language specifically and state your position, rather than your home-brew stuff, I'd have something more to respond to.

You have more to respond to with me using the language I prefer...but you would prefer to continue this silly game of "I don't like you."

Hey, no problem.

I like you.

 

[Mach]

So honestly the experiment kind of blows my mind and I don't know completely what to make of it..

While delayed choice experiments have confirmed the seeming ability of measurements made on photons in the present to alter events occurring in the past

mind tentatively blown

Yes I think it make take some time for me to try and wrap my head around this. I never heard of that (delayed choice quantum eraser) before, so interesting.

 

[Paleocon]

mind tentatively blown

Yes I think it make take some time for me to try and wrap my head around this. I never heard of that (delayed choice quantum eraser) before, so interesting.

It doesn't actually do that. The post-slit measurement makes the photon impact the screen as a particle, that's not to say it can actually have a backwards effect in time.

 

[Mach]

mach: Frank claims no one can be certain

I did?Where?

...it appears we truly cannot KNOW anything with any degree of absolute certainty.

==========================

You have more to respond to with me using the language I prefer...but you would prefer to continue this silly game of "I don't like you.".

Frank, I'm being serious, since when have I played games in these forums? Not even sure I know how. No need for accusations right off.
It works best if you response to the OP position. If you "agree with someone else", it's like a debate by proxy. If I pin you on something they said, you could just reply with "I never wrote that", etc. I'm trying specifically to AVOID games. And as I noted, if you instead just copy/paste your prior positions, since I have invested a lot of time in that already, its not game playing to inform you that i would not do so again. (hint that's called honest, and there is no negative connotation there).

 

[Mach]

It doesn't actually do that. The post-slit measurement makes the photon impact the screen as a particle, that's not to say it can actually have a backwards effect in time.

Yes, it says "seeming ability", which I'm taking to be that its a paradox (seeming contradiction). And being a real experiment testing a paradox, that involves time, I find that intriguing.
That you already understand the entire experiment is impressive. It will take me some time to bang on in it, with no guarantee of resolution

 

[Paleocon]

That you already understand the entire experiment is impressive.

Not really. Physics is my field, so I've known of it for some time.

 

[Nilly]

I'm not sure what you're trying to say. Of course the detector that the photon went to produces a different result than the one it didn't go to.

I suspect there may be a misunderstanding between us.

Not in the case of one photon, but in the case where you repeat the experiment.

No matter how many times you run the experiment, 2 detectors will always show an interference pattern. 2 detectors will always show a clump pattern. This is despite the fact that there is no empirical difference between the detectors from the photons point of view. If it was random (the emitted photons start life by going through slits randomly) then we would see a random distribution of clumps and interference patterns at each detector. But we don't. So it seems that our knowledge of the system (that some detectors give us which path info and some don't) predetermines the photons to act in a particular way.

What you're talking about is sometimes called the instrument effect (although the observer effect is it's true name). If you want to detect something, you have to fire a photon/electron/something at it (so it can reflect back to give you information) which affects what you're looking at.

The real weird thing about the delayed choice experiment comes later in the video, with the entanglement delayed-choice swapping. The usual confusion about the collapse of the uncertainty in QM comes from the fact that what 'collapses' when you look at it is the wavefunction, not the physical object. (The wavefunction is just a representation of the particle which contains all the possible information about the particle so it's not surprising that once the particles actual properties are known it shrinks down from a range of possibilities to just one). However the delayed entanglement swapping seems to bypass that, which really blows my mind. Realistically I'm going to put it down to quantum weirdness. The universe is a strange place (I posted about simultaneity earlier, which is equally fascinating but concerns relativity rather than QM). I revisit these experiments about once a year (I don't study physics any more so unfortunately my understanding seems to worsen over time rather than increase) but each time it never ceases to amaze me.

 

[Paleocon]

Not in the case of one photon, but in the case where you repeat the experiment.

No matter how many times you run the experiment, 2 detectors will always show an interference pattern. 2 detectors will always show a clump pattern. This is despite the fact that there is no empirical difference between the detectors from the photons point of view. If it was random (the emitted photons start life by going through slits randomly) then we would see a random distribution of clumps and interference patterns at each detector. But we don't. So it seems that our knowledge of the system (that some detectors give us which path info and some don't) predetermines the photons to act in a particular way.

What you're talking about is sometimes called the instrument effect (although the observer effect is it's true name). If you want to detect something, you have to fire a photon/electron/something at it (so it can reflect back to give you information) which affects what you're looking at.

The real weird thing about the delayed choice experiment comes later in the video, with the entanglement delayed-choice swapping. The usual confusion about the collapse of the uncertainty in QM comes from the fact that what 'collapses' when you look at it is the wavefunction, not the physical object. (The wavefunction is just a representation of the particle which contains all the possible information about the particle so it's not surprising that once the particles actual properties are known it shrinks down from a range of possibilities to just one). However the delayed entanglement swapping seems to bypass that, which really blows my mind. Realistically I'm going to put it down to quantum weirdness. The universe is a strange place (I posted about simultaneity earlier, which is equally fascinating but concerns relativity rather than QM). I revisit these experiments about once a year (I don't study physics any more so unfortunately my understanding seems to worsen over time rather than increase) but each time it never ceases to amaze me.

Quantum entanglement isn't my strong suit, so I can't address that.

But as for the rest, both the original detectors and the "erasers" interfere with the photon, so there's nothing strange about the fact that the erasers can reverse the effect of the original detectors.

But our knowledge itself certainly doesn't have anything to do with it. If you set up the detector so that it will produce the clump pattern, it'll still do so even if you don't read the results of the detector.

 

[CrabCake]

So honestly the experiment kind of blows my mind and I don't know completely what to make of it. Yes you're right that the method of observation affects the particle. But that's not the point. The point is that the method of observation is precisely the same no matter which detector the entangled photon goes to (D1 or D3). However the measurement is always different at each of D1 or D3. The only difference between the two scenarios is our knowledge of the rest of the setup.

There is a straight forward explanation:

Clipping: https://en.wikipedia.org/wiki/Clipping_(computer_graphics)

In a nutshell, if you are rendering a complex 3d graphics scene for a game or some other simulation, it doesn't make any sense to render parts of the scene that are not going to be displayed on the screen (portions of the game world that the player is either not looking at right now or are blocked by some other object). Thus, to save on processing power, memory, and other resources we don't bother rendering scenes that no one is looking at. If our existence were a computer simulation, the programmers would probably have used clipping in a myriad of places to save on resources. Thus, until a calculation is needed, it isn't actually performed. Ergo, photons that aren't being observed don't bother choosing a path (in order to conserve on processing power); our observation causes the calculation to take place and the photon to choose a path (because now that it is being observed, we do need to make that calculation and should no longer be clipping it).

This is the expected behavior of a universe that is actually a simulation running on a computer.

The problem with believing this, of course, is that if this belief is true and becomes widespread, we have to wonder whether the people running the simulation will still find the simulation useful. Once the intellects in the simulation start acting the way people aware they are in a simulation would act rather than continuing to act as if they were in a real universe, the simulation may no longer be of value to them. If the simulation is no longer useful to them, they may just turn it off or reboot it. So, it's in our interest never to find out.

cue X-files theme...

 

[Lethargic Aptitude]

The position of philosophical skepticism is something like this:

We cannot know anything about reality with certainty.

Or wiki:
(It is generally agreed that knowledge requires justification. It is not enough to have a true belief: one must also have good reasons for that belief. )
Skeptics claim that it is not possible to have an adequate justification.

Do you think this is correct? Why?

Please note this is different than scientific skepticism. Scientific skepticism is questioning whether claims about reality are justified scientifically...they are testable, evidenced, observable, etc. Scientific skepticism is really just applied science...or scientific inquiry, being critical, etc. Or the general definition of skepticism that is "to question". None of these types of skepticism is being addressed.

I 'sense' that there is going to be alot of confusion..in this experience.

Ironically most philosophical skeptics are dogmatic in their belief that nothing can be known with absolute certainty. But they are certain that you cannot know anything.

 

[Absentglare]

If you don't know, how can you know the above (you don't, it's a contradiction)


Of course we can differentiate true from false.
You did it yourself in making the above claim "we cannot know what is true". <-- Is that true? Contradiction again.


Defined direct access, and you'll see your error. I can observe a ball with senses and with senses via other sensors (electronic sensors).
You claim that's not direct access. What is this mysterious direct access? I argue that its nonsensical.

You don't seem to understand what i was saying.

We cannot distinguish with absolute certainty {what we know} from {what we think we know but is ultimately untrue}. Things that we justifiably believe that we know (our subjective, fallible mind makes this judgement) are not distinguishable- otherwise, they wouldn't be justifiable in the first place.

This is not controversial, i'm not making this up. Knowledge is (1) justified (2) true (3) belief. We cannot evaluate (2), from within our own minds, and we cannot reason independent of our mind. (1) and (2) are indistinguishable, but only (1) is measured.

The Analysis of Knowledge (Stanford Encyclopedia of Philosophy)

We cannot know what is true. That is not a contradiction. You're not understanding what i'm suggesting. {What we do know} is true. We do not know {the group of things we know (because they are justified true beliefs)} from {the group of things we think we know, but we don't (because they are justified beliefs but they are not true)}.

Science cannot possibly serve as proof of truth. Science can be used to derive future observations from present observations. The scientific method can be used to produce mathematical relationships between entities that can predict future behavior within some region of convergence.

What makes you think i must define direct access ? Let's say that nothing in the universe existed except my consciousness and i was thinking to myself about how i exist. That's direct access. That's why Descartes was the start of modern philosophy, he created the clean slate. Everything i perceive could be wrong, the whole planet might not exist. Maybe none of you exist and i'm plugged into the matrix. This is actually an age-old idea known as "brain in a vat." In such a case, the only thing i truly know is that i exist, at least in some form, so as to be able to be the subject of the deceit.

You fail to recognize that a "justified belief" is indistinguishable from "justified true belief" for reasons that i explained above.

 

[Absentglare]

This reminds me of the Gettier problem. Knowledge has been defined as justified true belief. Gettier showed that there are instances of justified true belief that are not knowledge. This arises from propositions in which something is true and belief is justified but there is no causal connection between the truth and the justification. So, if one's reasons are faulty then it's not really knowledge, and there's no widely accepted way to avoid this. It's one of the unsolved philosophical problems.

https://en.wikipedia.org/wiki/Gettier_problem

There are multiple solutions to the problem.

The easiest one, without even redefining what knowledge is, is by elaborating on the definition of "justified."

 

[Absentglare]

Including the above, which you are uncertain about. But you seem to claim it's "Truth"? It cannot be both, I'll leave you to resolve that contradiction and explain which was correct (?)


You can't be certain of that, so why propose it?

I'm writing that "we can be certain and uncertain" is consistent with most everything we are likely to discuss (and the rest wll be consistent only after a lot of back and forth).
"we cannot be certain" is inconsistent WITH ITSELF (we are certain that we cannot be certain...contradiction)

It's a contradictory premise and should be discarded as useless up front. You at least agree its useless, just for a slightly different reason

He's saying the same thing that i did- you cannot be absolutely sure what is true or not. I could be a brain in a vat and the planet Earth might not exist. That's possible because, as he said, the only interaction i have with the planet Earth are my senses, my mind.

So we cannot be absolutely sure what is true and what is not true (except i do know that i exist- but that's all that i know absolutely).

Further, skepticism of this nature is useless because we do not need absolute certainty of a claim to have a great deal of certainty about a claim.

"We cannot be certain," is not a contradiction. We cannot be certain that we cannot be certain. We cannot be certain that we cannot be certain that we cannot be certain. I could go on but Gödel probably wants me to stop.