I'm absolutely obsessed with the problem. I've seen many people dismiss it, and I've seen many arguments against it, none of which seem to cut the logical mustard. The problem for me boils down to "world-having". If something shows up in my world, I want to know if there is a way to determine if there is any kind of world connected to it, or if it is merely an object in my world.

But worlds seem necessarily exclusive and necessarily private (for even if you were to jump into the mind of another, then your previous body would be reduced to a representation in the new world - at any rate, it seems that only one mind can exist at a time). Any attempt by another to demonstrate the existence of their own world would necessarily be through means of a representation, which could just as well be copied by a mere object (philosophical zombie).

Even if we allow other experiences/minds/worlds to exist in an offhand way (like we might allow objects in space to exist outside of a perception field for various reasons, contra-Berkeley's idealism ), we cannot deny that our own experiences have a vitality and immediacy which affords them a different and singular quality of being.

  • "we cannot deny that our own experiences have a vitality and immediacy which affords them a different and singular quality of being." Yes, but everyone else feels the same way. Solipsism is a waste of time. It leads nowhere.
    – user4894
    Oct 25, 2014 at 7:06
  • 1
    Where do you want to go? Reminds me of people that say, "yes, but what will philosophy DO for me?". It won't do anything but give you a clear head!! I suppose if you're not deeply bothered by the problem of other minds (and why I'm bothered is obviously psychological in nature), then you won't find it as compelling.
    – Josh B.
    Oct 25, 2014 at 7:16
  • I think it'd be a good idea to ask yourself whether the 'inference of other minds' is a logical one to make. Dec 16, 2015 at 16:29

3 Answers 3


The approach that resonates with me is the "Gnostic proof of God" approach -- "If you are God, then why do you hate yourself?"

  1. If this were just your world, why would you constitute it in a way that makes you so unimportant and powerless?
  2. If your construction of this world in this way is not your choice, then whose choice was it?
  3. If it was your choice, then it seems to have an ulterior motive, which presumes someone out there you are impressing or otherwise affecting by surviving in a difficult world.
  4. Either way, you get to there being some other being that is the reason for the limitations you face in your world.

So most of us, at some level, really believe in either a 'Good' God providing possibility, or an 'Evil' God providing limitation, whatever form that God takes. To even imagine you are alone, seems to require being sure there is or was someone else. Why would that expectation come to be? How could a being that has always been alone miss company?

The only way out of this is Sarte's "Hell is other people", or its cheery parallel, but that is just distributing the personality of the "Evil" God, and makes for multiple people.

Put short, the fact that you reach out for others with worlds, suggests that you are constituted to do so, which lacks logic, if you are alone.

That it is natural to project that other as a God does not imply the other creatures are Godlike in any way, but only that you are able to idealize from constituents, and that constituents of Otherness are there. So this is not, for me (as it was for the Gnostics) a proof of God, but a proof that the basic notion of Other has some deeper reality.

  • Rest is not important -- important is the realization of Otherness in you, the feeling. As to your points Imagination is the answer to everything. We have to train our emotional imagination to understand how weak can be joy, or how WEAK can be not weak at all. Again you assume human to be weak and world to be a PROBLEM. There are NO problems in the universe. Only joy, sufferings, uncertainty and wonder. Maybe also others. You are wondering about PERSONALITY of god -> Forgetting how little we know about our OWN personalities -> And how evil can they be.
    – Asphir Dom
    Dec 1, 2014 at 0:10

There is a good summary of the Problem of Other Minds here at Standford's Encyclopedia of Philosophy. Although I don't believe they really pick up on the true application of the problem of other minds, which is determining if I can trust the objectivity of the world I perceive.

I'm coming to the conclusion that the problem of other minds needs to be understood as a trivial problem. And it really is better stated as "Do I perceive an objective world?" Some of the possibilities:

  1. I do perceive an objective world and other people who behave like they have a mind really do have other minds.
  2. I am really God and have constructed all of space and time, but am hiding that fact from myself (solipsism).
  3. I live in the Matrix. Some other people are really other minds (also plugged in), while some are simulated minds and/or computer programs (e.g. the Oracle, Agents, etc.).
  4. I am really a brain in a vat and this world is the simulation of someone controlling my reality in a variety of other ways.

If you want a deconstruction of anything other than #1 above it is simply Occam's Razor - what is the simplest explanation given the information we currently have, that doesn't create a higher order solution (with unseen/unknown/unknowable variables). Without some interaction with, or revelation from, other worlds/dimensions we must rule them out with this most basic rule of logic.

Note, however, that Occam's razor doesn't say that other solutions are not possible, it simply says that other solutions are not the best solution without any evidence supporting them.

The reason Occam's Razor is an effective deconstruction for any area that applies is that there is nothing practical that can be done with the alternatives, other than write a great movie script. Even if I am a brain in a vat - will that change the way I live? It shouldn't from a logical perspective. Not if you understand all the implications. I still have the same ability to think and interact with the universe (whether objectively real or simulated) and without any information on how to break out of the vat, my choices are no different.

Given that you are where you are, what are you going to do with your life? Even "ending your life" isn't a solution. Whoever is in control of you and the vat can just restart the simulation and plug you back in, or reincarnate you, or bring you to the next phase of the simulation - i.e. heaven/hell or whatever the afterlife is...

So, I take the position that any possible or real world, dimension, or force which does not interact with our world or reveal itself to us in some form or fashion, is irrelevant to my life. Granted, I believe this with a sort of blind faith.

Note that this is the basis for many worldview claims and clashes. The argument among adherents of various worldviews are generally arguing the validity of difference evidences for their faith. For example, is the the Bible real as a source of information/revelation that tells us about a greater reality than the objective world we directly experience. Is there such a thing as feeling the presence of God? Etc.

Skeptics attempt to deconstruct the evidence or even positively deny it (atheism, etc.). But in the case you describe, my examples #2-4 above - we have zero evidence for them, so they should be ignored. There is no reason even to debate among them. They can be trivially ignored, other than perhaps for use in thought experiments that attempt to discover some way of obtaining evidence about them.


First, you cannot know with certainty that you are awake, and therefore, when you interact with someone you cannot know with certainty that someone has a mind.

This is not just (Bertrand Russell's) teapot agnosticism, since there is a reasonable likelihood that you are indeed sleeping right now; you sleep every night, and from my experience with lucid dreaming it can be pretty tricky to realize that you are indeed dreaming from within a dream world, even when you consciously try to determine this question.

In fact, Bertrand Russell discusses this directly in his book Human Knowledge:

It may be said that, though when dreaming I may think that I am awake, when I wake up I know that I am awake. But I do not see how we are to have any such certainty; I have frequently dreamt that I woke up; in fact once, after ether, I dreamt it about a hundred times in the course of one dream. We condemn dreams, in fact, because they do not fit into a proper context, but this argument can be made inconclusive, as in Calderon's play, La Vida es Sueño (Life Is a Dream). I do not believe that I am now dreaming, but I cannot prove that I am not.

That said, if you assume that the world is real, and are only worried if you are the only mind in a world of philosophical zombies, then consider this argument:

1) If you are part of life evolving on earth,

2) Then your mind evolved by evolution, since it provided some evolutionary advantage.

3) Therefore, you are probably not the only instance of a mind.

  • 1
    This part at the end oddly lacks empathic perspective. If I doubted whether any of you were actually thinking, why would I believe the science that was a product of that thought?
    – user9166
    Oct 26, 2014 at 14:37
  • @jobermark, I do not understand your question.
    – nir
    Oct 26, 2014 at 19:56
  • 1
    Evolution, as an 'observed fact' involves much more faith that earlier humans are telling you the truth, than is required to believe that the people around you are telling you the truth about being conscious. Anyone who doubted the latter, would reject the former outright. So the argument from evolution does not seem to take the person asking the question seriously.
    – user9166
    Oct 27, 2014 at 17:02
  • @jobermark, I fail to see why that is true, and I at least am a counter example; I do not doubt evolution, but I doubt that all people are conscious in the same way; most people I talk with insist there is nothing in their inner experience which cannot be described mathematically, or expressed as a computation, and lately I started considering the possibility that it is true; but I also do not see any reason why that would make them bad scientist, engineers or philosophers; on the contrary, they generally highly intelligent and accomplished scientists, engineers, and philosophers.
    – nir
    Oct 27, 2014 at 19:20
  • The OP is doubting any others are conscious. So you can assume Darwin was not conscious, but would mechanically discover something as deep as evolution? That the discovery of evolution did not require that he honestly had the internal world of mental images he claims to have used to make his observations? Then you hold a definition of 'conscious' that I cannot share.
    – user9166
    Oct 27, 2014 at 19:39

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .