A "Fresh" Classification of various philosophical positions on "Does the external world exist?"

What are the different possible answers to the issue of relationship of perception and external world? Let's ditch all the confusing the epistemological labels, and use simply lay-man terminology. Broadly speaking, I think all the positions can be grouped as:

  • The Common Sense View: The world as we perceive it actually exists and is more or less similar to what we perceive it to be.
  • The Refined Common Sense View: An external world exists independent of human mind, and that external world is not the same as we perceive it to be, but what we perceive corresponds in some way to what actually exists.
  • External World Skeptic View: An external world may exist but we can know nothing about it and we have no reason to suppose that external reality corresponds in any way with our perceptions.
  • World as an Illusion View: This refers to all the various possible scenarios like my brain is placed in a vat and connected by wires to a computer which sends my brains the same impulses which a normal receives; we all exist in some computer program; we all exist in some work of fiction; what we are perceiving is actually a dream, etc etc.
  • World as God View: We exist inside the mind of God, and God is the cause of all our perceptions.
  • Solipsistic View: Only my mind exists and there is no external reality.
  • The Flux View: Reality exists, but it is actually in a state of flux with no concrete "facts", and the individual and collective consciousness of humans "molds" that flux into adopting one or the other state through our beliefs and actions.

Comments

Salman Latif said…
Most of them do agree to the notion that the external world can't be entirely trusted upon, considering the fickleness of our senses.
Butters said…
Pragmatism, baby! :P
Sony said…
I don't understand why there is a need to mystify everything... The common sense view (or the refined one) can be proven with logic, experience, observation etc. Whats the kick in spicing it up with creativity and compete with imaginary theories?
Awais said…
@ Sony

I believe in the refined common sense view, especially the version given by Bertrand Russell.

But it is mistaken to say that common sense or refined common sense view can be philosophically proved. It is the lack of strict proof which leads to a variety of possible answers. External world skeptic view is impossible to refute, but of course, it can't be proved either.
Sony said…
@ Awais

Of course it can be refuted. If I tell someone about my invisible apple that I'm holding in my hand, It is automatically assumed that I possess the capability/tools to perceive it. Similarly if those that cannot see the apple, develop that capability or come across that tool, they should be able to see the apple as well.

But if no such capability/tools exist, I'm basically putting across the idea that the invisible apple exists and can be seen with imaginary tools that nobody (including myself) possess. How different is that from the apple not existing at all?

One can only disprove something that was proven initially... or at the very least hypothetically sound or plausible.
Awais said…
I do not really understand what you mean to say with your invisible apple scenario. Do you mean to say that all the philosophical theories of external world apart from common sense are unverifiable and unproven, and hence are unworthy of even being considered for refutation?

Let's consider that you are holding an apple in your hand that is not invisible.

How do you know that you are actually holding an apple that exists independent of you? All that you can say with certainly is that you have the sensation of something round, with a fruity smell, that looks and tastes like an apple. All that you have are sensations. But how do you know that there is actually something out there causing these sensations? You may dream of holding an apple and feel the exact sensations and yet there would be no apple. Furthermore, you have never experienced causality itself, so how do you know that your sensations have actually been "caused" by something in the external world. And even if you assume that they have been caused, how do you know that that the cause is actually an apple? Your brain might be plugged to a computer simulation and you would be getting impulses from a computer making you think you are seeing an apple. You might be hallucinating, feeling an apple when there is none. The basic point is, there is no argument to show that sensation is necessarily linked to objects in the external world and that there is an exact correspondence between perception and reality. Of course, common sense assumes so. But there is no philosophical argument to prove this necessity.
Sony said…
Yup... that's exactly what I meant to say - "unworthy of even being considered for refutation".

If i had a visible apple in my hand, the smell, taste, etc all add to my perception of the apple's existence outside myself. But suppose its not really existing, and my brain is hooked on to a computer simulation that's making me hallucinate... and the simulation is complex enough to network multiple brains to be in sync with my "virtual" apple.... that is to say if I'm holding the apple in front of someone, the other person too sees the apple and smells it, etc.

So then by this theory, the computer that is running this software (metaphorically of course :) cannot exist because that too is subject to being a hallucination of one of its connected brains... It suggests that any argument one comes up within this "system" to show that sensation is necessarily linked to objects in the external world would naturally and automatically be disproved. It also implies that any knowledge gained or sensations felt by any of the connected brains is done so at the discretion of the one sitting behind the monitor.

On the other hand, I don't find anything derogatory in the "mere" senses touching and smelling the apple, taking for granted that it is very real, without the need to mystify it with his imagination of whether the apple is real or not. Its existence is proven by the fact that others around him see, feel the apple as well. That's the key difference in a dream. You feel the apple, but its not verified by anyone... dreams are very central to the dreamer. The physical interaction of the people with the objects in the external world is proof of its existence.

If you are equating causality as the waking up from a dream, and a "true" reality would be revealed, where everything makes ultimate sense, etc, I'm saying the possibility cannot exist because the idea came from one who did not "wake up" and is still dreaming.

So the common sense view (or refined) view it the only one that has any base... the rest is glorified garbage served well garnished :) hope that makes sense...
Awais said…
"unworthy of even being considered for refutation".

Well, then you should read the whole history of empiricism in philosophy, and see for yourself what elaborate arguments make it an important question.

and the simulation is complex enough to network multiple brains to be in sync with my "virtual" apple....that is to say if I'm holding the apple in front of someone, the other person too sees the apple and smells it.

How do you know that the other person actually exists? Maybe he is a part of the simulation itself, designed to see what you perceive to be an apple and smell it. The other person itself is just a bunch of sensations for you. How do you know he actually exists?

On the other hand, I don't find anything derogatory in the "mere" senses touching and smelling the apple, taking for granted that it is very real, without the need to mystify it with his imagination...

Exactly. You said it yourself. You are taking it for granted. You don't have any proof. You just like to believe your common sense, without having concrete proof that common sense actually represent the truth. It is a choice of convenience, or as Hume would say, a choice of "habit".

You feel the apple, but its not verified by anyone...

Lets say you dream that you show an apple to a person and that person tastes it and tells you that it is a real apple, and all this happens within the dream :)

The physical interaction of the people with the objects in the external world is proof of its existence.

Other people are also just a bundle of sensations.

The people who suggest the hooked-to-a-computer scenario do not present it as what is actually happening. They present it as a hypothesis for the plausibility of skepticism. You cannot refute the possibility that you are hooked to a brain, hence you cannot refute the possibility that external world is not what it seems to be, and hence you can never logically know anything about the external world with absolute certainty.

The simple common sense view is actually very easily refuted if we accept modern physics. What you think is actually a "solid" apple is in reality 99% vacuum, consisting of electrons revolving around a tiny nucleus, itself consisting of numerous tiny particles, which are probably composed of unidimensional strings resonating with energy waves... all these things which you cannot actually perceive. The crunching sound that you hear when u take a bite, there is no actual "sound". In reality, there is just movement of particles of air. The taste that you perceive. The molecules have no "taste". There are just molecules binding with molecules of your tongue. There is no "smell". That is just molecules binding with the molecules in your nose. So, if you are to accept modern physics, common sense view is simply dismissed :) the only thing that remains is the refined common sense view, but that cannot be proved. It can only, as you termed it, taken for "granted". But skeptic philosophers don't like to take things for granted.
Sony said…
I think it would be inappropriate to mix philosophy with modern physics, simply because when seen through electrons and strings, an apple is an orange and an idea or a thought is nothing more than a positive charge at the end of some neuron. That would negate the need for philosophy or discussions. It would be an end in itself, leading to no progress.

Now if one is looking for proofs, then it is automatically assumed that they accept and take the first principles' existence for granted... or they cannot accept a proof, simply because the concept of proofs... ie deriving conclusions based on first principles, cannot exist. That applied to skeptic philosophers as well. Thought by itself cannot exist without accepting the first principle that a person can think. If he questions whats the proof he can think, how can you prove that thought is really his, etc... then they're not really looking for an answer. Ironically even the question cannot exist.

So when other people around me could theoretically be a bunch of simulated sensations, its basically assuming I'm the only one who really exists and the rest are imaginary. If that were possible, and multiple people thought the same, each of them would have a parallel simulated "reality" of their own. But that's not the case is it? Hitler killed the Jews in my reality... and I'm pretty sure he did the same in his reality as well. Thus I'm coming to the conclusion that both me and him exist in a common reality. Now with that information laid down, I don't see how I can see myself as real and him a bunch of simulated sensations. I don't see any reason or need to. I can be skeptical about a lot of things, but not his existence. That common reality we share is the external world.
Awais said…
I think it would be inappropriate to mix philosophy with modern physics.

It's not inappropriate. Why should philosophers ignore what science supposes to tell us about the world? All science was once philosophy. In fact, there is a whole branch known as philosophy of science.

That would negate the need for philosophy or discussions.

No, it doesn't negate the need for philosophy. I cannot even remotely see the how this conclusion can be arrived at.

What is wrong with saying "If you accept modern physics..."
Why, don't you accept modern physics? If you do, then to be consistent, you have to consider it. And if you don't, then isn't it weird that you are willing to accept your common sense but eager to deny science?

Now if one is looking for proofs, then it is automatically assumed that they accept and take the first principles' existence for granted.

No, that is not true. Why do we have to accept something to look for a proof for it? I can be highly skeptical of something and still look for its proof. It is not automatically assumed.
Furthermore, there is a thing like "Let's consider it true for the purpose of discussion..." in philosophy, which philosophers often use to discuss things which they may not accept but wish to analysis.

If he questions whats the proof he can think, how can you prove that thought is really his.

This is the classic scenario of Cartesian hyperbolic doubt... If a person can doubt, then it is indubitable that he can think, because if there is a doubt, there has to be a thought. Descartes' Cogito ergo sum, "I think therefore I am".

its basically assuming I'm the only one who really exists and the rest are imaginary. If that were possible, and multiple people thought the same, each of them would have a parallel simulated "reality" of their own.

You keep missing the point. How do you even know that "multiple people" exist? You assume it, but how do you actually know? All you know is that you exist. And if the rest are all just a bunch of sensation, then they don't exist, and there wouldn't be "multiple people" and there wouldn't be a Hitler, apart from being a figment of your imagination, and he wouldn't have a reality.
Sony said…
I did not say anything about ignoring science... that would be completely absurd. In fact they go well together. I was specific to modern physics... string theory, electron movements, etc. When you go to such a microscopic level, philosophy or thought cannot be applied to it. Rocks, fruits and humans are all the same in that level. I think it needs to be zoomed out a little for any discussion to happen... ie a person should be someone with cognitive abilities, gravity, etc and no a collection of carbon molecules.

When you say you can be highly skeptical about something, and still look for its proof, do you mean you can look for proof of something's existence, without accepting that it can exist? Where's the logic in that? Its automatically assumed that it exists (or can exist), so the process of looking for proof justifies the action. I did not say anything about accepting anything first to look for proof... just the acceptance of its existence.

I do understand the "lest assume this is true, etc" discussion and the Cartesian doubts, but I'm talking about the existence of the outer world. I'm not missing the point either. Let me elaborate... I'm simply starting off with the fundamental thought process that I exist. Then I see other people exist around me, but I'm keeping in mind they might not exist n could be a hallucination. Now I'm going into the "Lets suppose they are real" hypothetical argument. The sole reason for going into that mode is to verify the integrity of what I see.. whether they are real or not. So I'm "assuming" there are other people. But when I do that, If i find their reality is the same as mine, I am coming to a conclusion that they are equally valid as me when it comes to the doubt of their existance. So either both of us has to be real, or both of us has to imaginary. The hypothesis of me being real and the rest of them not real can be eliminated like that. So it makes sense to say that the external world is very much real and what we perceive (and refined when it comes to seeing some things with tools).
Awais said…
When you say you can be highly skeptical about something, and still look for its proof, do you mean you can look for proof of something's existence, without accepting that it can exist? Where's the logic in that?

Why do you assume that either you accept something or you do not accept something? There is also a third situation, far far more common in philosophy: that you are doubtful about something, uncertain, in between acceptance and non-acceptance. I can look for proof of something's existence, while at the same time accepting the possibility that it may not exist.

So I'm "assuming" there are other people. But when I do that, If i find their reality is the same as mine, I am coming to a conclusion that they are equally valid as me when it comes to the doubt of their existance.

But how do you find out that their reality is the same as yours? Because apart from your assumption that they exist, you have no empirical access to their supposed reality. You only have access to your own reality. You can only try to imagine what their reality would be like if it existed. But this imagination doesn't prove anything.
I cannot see how the leap from "Let's assume other people exist" to "Therefore, other people exist" is logically justified.

Since the discussion is getting long-winded, i'll repeat my main stance so that that is not lost from our sight :)

I maintain, and so does the philosophical community actually, that it is impossible to refute the possibility that I might actually be existing in a simulated reality, with all the people i perceive being a part of that simulated reality.

And secondly, I maintain that it is impossible to logically prove the common sense view of the world, and the only option is to take it for granted.
tehzib said…
I just found this entry after ages: the link was lost on my FB wall somewhere :P

The view you describe as 'solipsism' is not exactly solipsism. Solipsism is the view that one's own mind is the only *mind* that exists, not necessarily the only *thing* that exists. What you described is skepticism of the external world (number 3 in your list).

Other than that, this is a pretty neat classification. My own view is the common sense one, i.e. I believe in an external world that is knowable.