Solipsism Refuted Absolutely, or: A World Exists Outside Your Mind!

[Flagg]

Solipsism is the view that only I exist, i.e. only my consciousness and the contents of my consciousness exist.

I've formulated an argument that proves with absolute certainty that solipsism is false, but I wanted to know everyone else's take on the subject before I present my own take. Thoughts? EDIT: I put it here so it can be viewed on future pages.

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My proof of the impossibility of solipsism, and therefore of the absolute certainty of the existence of an outside world, is taken by assuming solipsism as to not beg the question, and demonstrating how such a position leads to logical collapse. The following is reprinted from my blog. Looking forward to comments and criticism!

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A Logically Absolute Proof of the Existence of a World Outside My Mind

One of my philosophy professors, Dr. Stewart, used to pose hilariously to his classes the scenario of killing himself to end all of existence by pointing his forefinger to his head, hand in a gun-shape, and screaming "STOP OR I'LL KILL YOU ALL!"

Throughout almost all of professional philosophy, the question of whether one can absolutely verify the existence of a world outside our consciousness has been considered open and perhaps even unanswerable for thousands of years. Indeed, an absolute proof of the impossibility of solipsism by a professional philosopher would throw the philosophical community - or, more likely, bring that professional under extreme ridicule, since many philosophers (unlike Dr. Stewart, who regards it as a thoughtful joke) enjoy hanging this over the heads of others as a verification of the old canard that "you can't prove anything!" A proof is long overdue, and since professional philosophers cannot afford the risk of giving an irrefutable one, I thought I would present one myself.

For those of you unfamiliar with the A-time theory/B-time theory split, a brief explanation is necessary here before my disproof is given. A-time theorists, to paraphrase Dr. Craig, hold that things and events aren't equally real - only the present is metaphysically true; the past is no longer the case and the future will be the case, but it is absolutely true from every vantage in the universe that they are not currently the case. Only the present is such.

B-time theorists hold that there exists a point of reference by which the past, present, and future as experienced illusory by men all are true metaphysically. They are ordered by a temporal relation "before" and "after," where "a is before b" means simply that the truth of b requires the truth of a, but that the truth of a does not require the truth of b (simultaneous occurrence would require both).

To illustrate the difference more clearly, A-time theorists simply state that the universe exists in the temporal progression of one state to another. Thus, the notion of "x begins to exist," loosely, is that x exists over a timespan of finite measure. Yesterday has happened; tomorrow will happen; today is happening. B-time theorists hold that something's temporal existence (i.e. the whole of "yesterday") is simply extended finitely, exactly like a ball is finitely extended in space, when the universe as a whole is taken under consideration. This is what I think is usually meant by referring to time as "the fourth dimension."

That we perceive the "A-theory" of time is granted by the B-time theorist, but the B-time theorist states that this is due to our role as part of the universe, and that ultimately, this is, as stated previously, an illusion, as from the perspective of the entire universe all the past, present, and future simply exists in terms of ordered extensions in a dimension of space representing temporality. Thus, nothing begins to exist, even if its existence is finite in the time-dimension; it is simply finite in time-extension and no more begins to exist by virtue of this fact than a yardstick begins to exist by virtue that it has edges.

Note that if solipsism is true, then A-time theory is absolutely true, since the fact that we perceive a progression of events means that this is exactly the case, due to no other outside point of perception being at all possible. Therefore, all of our perceptions began to exist.

Now, under A-time theory, everything that begins to exist has a cause (under B-time theory, it needen't have a cause; it just *is*). A "cause" is the action of one entity upon another entity with the "effect" being the result of this action in accordance to the nature of the interaction of these entities. The nature of a bat and the nature of a ball, for example, entail that if the ball is hit by the bat, it goes flying, all things in context being fairly granted. Since "nothing" has no properties, i.e. no identity, and thus does not exist, then everything that begins to exist in A-time theory must be caused by other things or must be caused by itself, and that action must occur before the effect or in simultaneous relation to the effect (i.e. quantum entanglement).

Given solipsism, first note that I must begin to exist, because my perceptions are in motion and because this motion has not always been occurring. Thus, I have a cause, and if solipsism is true, I must have caused myself to begin to exist. This leaves three possibilities: I caused myself to begin to exist before I began to exist, a contradiction; or, that I caused myself to begin to exist at a later state of my existence, which would entail that the effect precedes the cause, an impossibility by definition; or, most plausibly, that I caused myself to begin to exist simultaneous to the moment of my beginning.

The latter statement is all that's left for solipsism at this point, so refuting it renders solipsism literally impossible. Note first that since my perceptions themselves began to exist, they must have a cause (they can't exist as "brute fact," as people positing solipsism love to say, since A-time theory is absolutely true under solipsism and thus it is absolutely certain they must have a cause). This cause must either be due to other perceptions, or due to a creative ability inherent in myself. At the moment when I began, my first perceptions cannot have been caused by previous perceptions, or else it was not the first moment when I began. Therefore, my creative faculty must have (simultaneously with my beginning) caused them to begin to exist. Furthermore, my creative force must itself begin to exist with a content with which to create, since it would otherwise be empty (as I have not perceived at the moment of my beginning) and thus would lack any means of creative power, since there would be nothing by which it has means to create - even God has an idea of what He creates if we presume theism and creation out of nothing on that account. So, I must begin to exist with some preconceived notions of what I cause to exist at my beginning. Therefore, these notions must themselves have a cause.

Since no other outside force (evolutionary processes, a nasty god, etc.) exist to supply these notions, and since these notions cause the perceptions to begin to exist (and thus, by logical precedence, cannot caused by these perceptions), we have nothing left to supply their necessary cause. Therefore, I could not have caused myself to begin to exist simultaneously at the beginning of my existence.

Therefore, we have nothing left to supply the necessary cause of the self under the assumption of solipsism. But this is a logical contradiction.

Therefore, an outside world exists absolutely, 100%, objectively, irrefutably, and inarguably exists by the impossibility of the contrary. So quit positing that it could possibly be "all in your head". =P

Edited April 14, 2009 by Flagg

[BaalChatzaf]

Solipsism is the view that only I exist, i.e. only my consciousness and the contents of my consciousness exist.

I've formulated an argument that proves with absolute certainty that solipsism is false, but I wanted to know everyone else's take on the subject before I present my own take. Thoughts?

Of course you have. How could anyone, who is, after all a figment of your imagination argue against you.

Ba'al Chatzaf

[Alfonso Jones]

Solipsism is the view that only I exist, i.e. only my consciousness and the contents of my consciousness exist.

I've formulated an argument that proves with absolute certainty that solipsism is false, but I wanted to know everyone else's take on the subject before I present my own take. Thoughts?

Go ahead and provide your argument. I imagine almost everyone on OL has had to argue with an alleged solipsist before.

Of course, if the alleged solipsist were really a solipsist they wouldn't argue - because they wouldn't concede that there was anyone to argue with (or to concede a point to).

Bill P

[Dragonfly]

Solipsism is the view that only I exist, i.e. only my consciousness and the contents of my consciousness exist.

I've formulated an argument that proves with absolute certainty that solipsism is false, but I wanted to know everyone else's take on the subject before I present my own take. Thoughts?

I think solipsism is useless, but it is not false, it can be a fully consistent and logical viewpoint. Only from a practical viewpoint the solipsist has to develop a theory for describing his "world" that will be isomorphic with the notion of an external reality that is independent of his consciousness, if he doesn't want to have continuously the feeling that he's terribly thirsty or is walking into walls etc. Now the common sense reaction is that if it quacks like external reality, etc. But there is no way you can prove that, solipsism is unfalsifiable. It's interesting that Rand was in fact defending a solipsist viewpoint when she said: "I will not die, it's the world that will end."

[Dragonfly]

Of course, if the alleged solipsist were really a solipsist they wouldn't argue - because they wouldn't concede that there was anyone to argue with (or to concede a point to).

That argument doesn't hold. Solipsism doesn't necessarily mean complete passivity like watching a movie, it's more like acting in a dream. In a lucid dream you might realize that you're dreaming, and still "act" in your dream (like arguing with other people, even if you know that they're only figments of your imagination).

[Alfonso Jones]

Of course, if the alleged solipsist were really a solipsist they wouldn't argue - because they wouldn't concede that there was anyone to argue with (or to concede a point to).

That argument doesn't hold. Solipsism doesn't necessarily mean complete passivity like watching a movie, it's more like acting in a dream. In a lucid dream you might realize that you're dreaming, and still "act" in your dream (like arguing with other people, even if you know that they're only figments of your imagination).

If the solipsist believes they are the only "person in the universe" (whatever that would mean in that context) then why are they conversing? With whom?

Or are they maintaining that they are delusional? Seriously!

Bill P

[Flagg]

But there is no way you can prove that, solipsism is unfalsifiable. It's interesting that Rand was in fact defending a solipsist viewpoint when she said: "I will not die, it's the world that will end."

Peikoff, in a recent radio program, pointed out that her statement came from a poet named Badger Clark, called The Westerner. The statement itself doesn't actually appear in Clark's poem, although "the world began when I was born" does - and in the context of the poem, this means that what previously existed before his birth (and what will exist after death) is by definition irrelevant to one's existence, unless one's concern for the future of something one experiences while alive is itself a value. Rand further clarified in that same interview that we won't wake up at some point after death and say "woah, how terrible it is that I'm a corpse!" That's what she meant - not that solipsism is the case.

Anyway, my absolute disproof will follow this post, and you can put that worry that we all could just be in your head to rest. ;)

[SherryTX]

Of course, if the alleged solipsist were really a solipsist they wouldn't argue - because they wouldn't concede that there was anyone to argue with (or to concede a point to).

That argument doesn't hold. Solipsism doesn't necessarily mean complete passivity like watching a movie, it's more like acting in a dream. In a lucid dream you might realize that you're dreaming, and still "act" in your dream (like arguing with other people, even if you know that they're only figments of your imagination).

When I was a kid, there was a movie on (I think) PBS where at the end, it was revealed that the world that was shown was just some guy's dream. I think it was by Mark Twain...anyone remember that? Sorry - a bit off topic, but it got me thinking about it.

[Flagg]

Put the proof in my original post, so future pages can have it ready for commentary.

Edited April 14, 2009 by Flagg

[Dragonfly]

Now, under A-time theory, everything that begins to exist has a cause

Why? That we often find causes for events doesn't mean that this always must be the case. That is the fallacy of induction. So your argument has already been derailed at this point, no need to read further...

[Dragonfly]

If the solipsist believes they are the only "person in the universe" (whatever that would mean in that context) then why are they conversing? With whom?

Why are you conversing in your dreams? And with whom? This is the same error as thinking that determinism would mean that people wouldn't make any choices. Suppose you meet a gorgeous woman in your dream, would you ignore her when you'd know somehow that it was only a dream?

Or are they maintaining that they are delusional? Seriously!

Ridicule is not a good argument here, "delusional" has negative connotations, it suggests some psychological problems, they'd probably say that reality is an illusion in the sense that the "reality" in a dream is an illusion. You won't be able to make a logical argument against solipsism.

[Flagg]

Now, under A-time theory, everything that begins to exist has a cause

Why? That we often find causes for events doesn't mean that this always must be the case. That is the fallacy of induction. So your argument has already been derailed at this point, no need to read further...

Good point; you do have to accept the Randian state-state nature of causation as I have written it, but supposing you are right - let's define cause as "a causes b means that not-a entails not-b." This is the generally accepted view of causation.

Curiously, my argument still follows from this definition.

Name one event within time that does not have a cause under the definition of "cause" I just gave.

[Alfonso Jones]

If the solipsist believes they are the only "person in the universe" (whatever that would mean in that context) then why are they conversing? With whom?

Why are you conversing in your dreams? And with whom? This is the same error as thinking that determinism would mean that people wouldn't make any choices. Suppose you meet a gorgeous woman in your dream, would you ignore her when you'd know somehow that it was only a dream?

Or are they maintaining that they are delusional? Seriously!

Ridicule is not a good argument here, "delusional" has negative connotations, it suggests some psychological problems, they'd probably say that reality is an illusion in the sense that the "reality" in a dream is an illusion. You won't be able to make a logical argument against solipsism.

Ridicule is an appropriate response to such a position. Entirely appropriate.

And I mean the connotations tied to delusional, if somebody is serious about their solipsism.

Bill P

[Dragonfly]

Name one event within time that does not have a cause under the definition of "cause" I just gave.

The decay of a radioactive atom.

But even if I couldn't find such an example ("I can't find a black swan"), that wouldn't imply that such an example ("the black swan") doesn't exist.

[Flagg]

Ridicule is an appropriate response to such a position. Entirely appropriate.

And I mean the connotations tied to delusional, if somebody is serious about their solipsism.

Bill P

No need for anyone to be serious about it. I just refuted it in logical format, so it cannot be considered because it leads to inevitable logical collapse.

By the way, if one does not accept my view of causation, and asserts that things may still begin to exist without a cause whatever their definition of cause may be (the loosest form is that "a causes b" means "not-a entails not-b"), then the solipsism assumption renders this impossible - if, assuming solipsism, a percept A began to exist uncaused, then there is necessarily no connection between it and my consciousness. At most, A can only have the property of being coterminal with my consciousness, since if it had dependence on my consciousness, then my consciousness causes its existence continuously even if it began to exist uncaused. But even if A simply is coterminal with my consciousness, this means that the fact that it has no necessary dependence on my consciousness entails that it must exist independently of my consciousness, refuting solipsism. So under the assumption of solipsism, everything in the content of my consciousness must be caused by my consciousness, including their first state at their beginning, entailing my consciousness caused their beginning to exist. The argument thus still follows.

[tjohnson]

Throughout almost all of professional philosophy, the question of whether one can absolutely verify the existence of a world outside our consciousness has been considered open and perhaps even unanswerable for thousands of years.

This illustrates the uselessness of "professional philosophy", I daresay.

[Brant Gaede]

Throughout almost all of professional philosophy, the question of whether one can absolutely verify the existence of a world outside our consciousness has been considered open and perhaps even unanswerable for thousands of years.

This illustrates the uselessness of "professional philosophy", I daresay.

I took a philosophy course in college. One prof, hundreds of students and lots of graduate student assistants.

After a few weeks of unmitigated, incomprehensible nonsense, I withdrew from the class.

As for this thread I have no need to prove there's a reality outside my head and I'm amused by those who do feel that way.

Most philosophy is much to do about nothing. Even Objectivism isn't properly integrated with psychology. Philosophy and psychology are one thing in a human being but abstracted out by the German education model into completely different disciplines flapping around on the floor out of the water, so to say.

--Brant

[tjohnson]

I took a philosophy course in college. One prof, hundreds of students and lots of graduate student assistants.

After a few weeks of unmitigated, incomprehensible nonsense, I withdrew from the class.

As for this thread I have no need to prove there's a reality outside my head and I'm amused by those who do feel that way.

Most philosophy is much to do about nothing. Even Objectivism isn't properly integrated with psychology. Philosophy and psychology are one thing in a human being but abstracted out by the German education model into completely different disciplines flapping around on the floor out of the water, so to say.

--Brant

Hey, you said you weren't posting until May 1

[Brant Gaede]

I took a philosophy course in college. One prof, hundreds of students and lots of graduate student assistants.

After a few weeks of unmitigated, incomprehensible nonsense, I withdrew from the class.

As for this thread I have no need to prove there's a reality outside my head and I'm amused by those who do feel that way.

Most philosophy is much to do about nothing. Even Objectivism isn't properly integrated with psychology. Philosophy and psychology are one thing in a human being but abstracted out by the German education model into completely different disciplines flapping around on the floor out of the water, so to say.

--Brant

Hey, you said you weren't posting until May 1

I'm his evil twin.

--Brant

[Dragonfly]

By the way, if one does not accept my view of causation, and asserts that things may still begin to exist without a cause whatever their definition of cause may be (the loosest form is that "a causes b" means "not-a entails not-b"), then the solipsism assumption renders this impossible - if, assuming solipsism, a percept A began to exist uncaused, then there is necessarily no connection between it and my consciousness. At most, A can only have the property of being coterminal with my consciousness, since if it had dependence on my consciousness, then my consciousness causes its existence continuously even if it began to exist uncaused. But even if A simply is coterminal with my consciousness, this means that the fact that it has no necessary dependence on my consciousness entails that it must exist independently of my consciousness, refuting solipsism. So under the assumption of solipsism, everything in the content of my consciousness must be caused by my consciousness, including their first state at their beginning, entailing my consciousness caused their beginning to exist. The argument thus still follows.

No, because your argument is based on your world view, not on that of the solipsist. You see consciousness as something embedded in an external reality. Not so the solipsist, to him his consciousness is the equivalent of reality, it is axiomatic, just as existence is axiomatic for Rand. Saying to him that his consciousness causes something is meaningless to him, just as it is meaningless to say that reality "causes" something. Everything he observes he considers to be part of his consciousness, just as we everything that we observe consider to be part of reality. You may find this a silly position to take, but it is logically unassailable.

[Flagg]

You see consciousness as something embedded in an external reality. Not so the solipsist, to him his consciousness is the equivalent of reality, it is axiomatic, just as existence is axiomatic for Rand. Saying to him that his consciousness causes something is meaningless to him, just as it is meaningless to say that reality "causes" something. Everything he observes he considers to be part of his consciousness, just as we everything that we observe consider to be part of reality. You may find this a silly position to take, but it is logically unassailable.

The proof proper does not assume that consciousness is a member of external reality, because that would be begging the question in favor of my conclusion. And for the solipsist, consciousness is the whole of reality, yes. But if the solipsist is consistent, he will discover that his position logically collapses, as I demonstrate above. The proof I gave was assuming the case of solipsism and reaching a contradiction.

1. If solipsism is true, then everything that begins to exist has a cause, and this cause must be my perceptions or by an internal faculty able to cause perceptions.

2. The first state of my perceptions began to exist.

3. Therefore, my perceptions must have a cause.

4. (From 1) This cause must be my internal faculty that is able to cause perceptions to begin to exist.

5. My internal faculty that causes perceptions must have a content.

6. This content itself began to exist.

7. Therefore, this content has a cause.

8. This cause cannot be itself and cannot be from perceptions.

9. Therefore, solipsism is false.

[Alfonso Jones]

I am trying to avoid breaking out into laughter at the thought of carrying out a long, detailed conversation with someone who maintains the solipsist position.

Who do they think they are conversing with? If someone other than themself . . . then they don't subscribe to their own nominal position.

What means do they use to obtain information? If anything other than introspection, ditto.

The challenge to the solipsist is to live consistently in a rational manner, based on their own assumed position.

Death looms.

I'm reminded of a passage from OPAR:

"If so, one might ask, how does one answer an opponent who says: 'You've demonstrated that I must accept your axioms if I am to be consistent. But that demonstration rests on your axioms, which I don't choose to accept. Tell me why I should. Why can't I contradict myself?' There is only one answer to this: stop the discussion..... No one can think or perceive for another man. If reality, without your help, does not convince a person of the self-evident, he has abdicated reason and cannot be dealt with any further."

Bill P

Edited April 14, 2009 by Bill P

[Dragonfly]

1. If solipsism is true, then everything that begins to exist has a cause, and this cause must be my perceptions or by an internal faculty able to cause perceptions.

No. You cannot prove that everything that begins to exist has a cause, so that invalidates the argument. There are more points in your list that won't work, but that isn't important as the first point already fails.

[Alfonso Jones]

I took a philosophy course in college. One prof, hundreds of students and lots of graduate student assistants.

After a few weeks of unmitigated, incomprehensible nonsense, I withdrew from the class.

As for this thread I have no need to prove there's a reality outside my head and I'm amused by those who do feel that way.

Most philosophy is much to do about nothing. Even Objectivism isn't properly integrated with psychology. Philosophy and psychology are one thing in a human being but abstracted out by the German education model into completely different disciplines flapping around on the floor out of the water, so to say.

--Brant

Hey, you said you weren't posting until May 1

I'm his evil twin.

--Brant

We're glad your evil twin has joined us, Brant.

Bill P

[Flagg]

1. If solipsism is true, then everything that begins to exist has a cause, and this cause must be my perceptions or by an internal faculty able to cause perceptions.

No. You cannot prove that everything that begins to exist has a cause, so that invalidates the argument. There are more points in your list that won't work, but that isn't important as the first point already fails.

Actually, I can prove that everything that begins to exist has a cause under the assumption of solipsism, for, if not, then a causeless percept necessarily has no ties to my consciousness (or else my consciousness would cause its existence, refuting the objection). Since it has no ties to my consciousness, it exists independently of my consciousness even if its existence is coterminal with the existence of my consciousness. This refutes solipsism, since something exists indepedently of my consciousness. So under the assumption of solipsism, everything that begins to exist must have a cause by the impossibility of the contrary. So my argument still stands.