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Is reality only in the mind?

  1. Aug 4, 2006 #1
    Is reality created in the mind or is there an objective reality outside of the mind? It almost seems like an absurd question and most people would say the latter but some philosophers are skeptical.

    If you have a candy bar in front of you, you assume that it exist because you can see it. The light from the candy bar reaches the eyes and the electromagnetic signals are sent to the brain where an IMAGE of the candy bar is created. So as far as we know the candy bar only exists in the mind. If you reach out and touch the candy bar the nerves in your fingers send information to the brain and the feeling of the candy bar is created in the brain. Once again the candy bar appears to be only created in the mind. You can taste the candy bar but once again the taste buds on the tongue sends signals to the brain where the taste of the candy bar in interpreted. You can drop the candy bar on the table and it makes a sound which is vibrating air molecules that vibrate the eardrum and the signals that go to the brain are interpreted there. Once again the sound of the candy bar is created in the mind. When you smell the candy bar the same thing happens. The smell is created in the mind. All the information we gather about the “outside” world comes through the senses and gets processed in the brain. There is no way to step outside of you and see if there is really a world “out there”. We have to trust our sense and they do not always provide us with valid information. There are hallucinations, mirages, optical illusions and bias beliefs of the person’s thoughts that can created false truths and even delusions We dream every night and while dreaming we believe these dreams to be reality only to find that when we wake up they were fantasies created by the subconscious. How do we know that our waking state is some sort of dream? We can ask other people about their reality but they too are interpreting the world through the senses and the mind, which cannot be trusted. To take skepticism to an extreme, you cannot even be sure that other people exist.

    I have thought about philosophical skepticism to some extent and my theory is that there is PROBABLY a world independent of the mind. We are pretty sure that the universe is billions of years old and it has existed for billions of years before there were any observers in it so I have come to the conclusion that there probably is an outside world but no matter how hard we try, we can never prove beyond a shadow of a doubt that this is the case.

    There is also the issue of the limitation of the senses. White light is a tiny sliver of the electromagnetic spectrum so what we see is not all that is out there. Rattlesnakes see in infrared and butterflies and bees see in the ultraviolet. What would the world look like if our eyes could see this part of the spectrum? What if we had x-ray vision? Elephants hear in ultra-low frequencies. Dogs can hear high frequencies. What does the world really sound like? Hound dogs have a very acute sense of smell. What does the world really smell like? Fish have lateral lines in their bodies where they can feel the outer world. What does the world really feel like? We really don’t know all that is out there due to the limitations of our senses and the abilities (or lack of) of the mind. Will we ever know the truth of reality?
  2. jcsd
  3. Aug 4, 2006 #2
    It is my opinion that any observer in the world will only see "their portion", their assigned portion of the universe.

    Only god can see every part of the spectrum, hear every frequency, smell every smell and feel every touch.
    What this means to me personally is that none of that really matters.
    For one we have science, so we aren't completely oblivious to what we cannot sense, but also for us personally, we have everything we need, we are built that way.

    As for the whole solipsism thing.. Well it's unfalsifiable to a degree, but then again what does that tell us?
    It tells us nothing.
    Even god has the curse of solipsism.
    Why? Because nobody can ever fully understand the system they are built in/upon.
    By logic, we can say that anything must be built on some kind of system, thus even god would need a system to run him.

    Note that I am in no way talking about a religious god here, I'm talking about an omnipotent and omniscient creator, simply for the purpose of contrasting our existence to one of a such a god.

    My conclusion is that infinite regress is everywhere, at all times, no matter where you are, who you are.
  4. Aug 4, 2006 #3
    "The light from the candy bar reaches the eyes and the electromagnetic signals are sent to the brain where an IMAGE of the candy bar is created."

    yes: that is what science says. The candy bar is real, the light i sreal,
    the eye is real, the brain is real...

    "So as far as we know the candy bar only exists in the mind."

    No. The scientific knowledge that tells us there is a chain
    of events linking the candy bar to neural activity in the brain regards
    every stage of the brain. Science does not warant
    regarding the brain as the only real part of the whole chain
    of events.

    Solispsistic argumnts try to make a selctive appeal to some parts of the scientific picture whilst ignoring others.
  5. Aug 4, 2006 #4
    The mind does not create the object [O] of reality (e.g., the candy bar), the mind creates a mental image [O-M] where the object and the mind unite to form a dialectic electro-chemical wavefunction within neurons. Thus exists what can be called a veiled reality of [O] within the mind. In this philosophy (called Objectivism:http://en.wikipedia.org/wiki/Objectivist_philosophy) both [O] and [M] are real, that is they exist as things independent until united via observation (e.g., perception). Thus we can never "know" pure [O] as reality, we can only "know" the veiled reality of the image [O+M], but the pure reality of both [O] and [M] as objects that exists holds true. Now, do not be confused by those that would claim this is an example of naive reality--this is false. Naive reality holds that pure reality is the image [O+M] and that neither [O] nor [M] are real as independent objects, e.g., that the real emerges from the unreal, naive indeed.
  6. Aug 5, 2006 #5
    Excellent Rade.
  7. Aug 5, 2006 #6
    If reality is in the mind, why would you say "only?"
  8. Aug 5, 2006 #7
    The problem with thes types of situations is that they're unproveable, but you can't disprove them either. Solipsists believe everything in the world is created through stimuli from their own subconsiousness (or something to that effect). See stuff like the "Brain in a Vat" experiment.

    (And no, not even "I think, therefore I am" works to disprove stuff like virtual worlds because you could easily be programmed/etc. to think that you actually do think, and have a conciousness.)
  9. Aug 5, 2006 #8
    Could you?
    How would you go about programming such a thing?
  10. Aug 7, 2006 #9
    I use programming broadly. You have to realise that there are possibly many stimuli we aren't aware about. Just like bacteria could have no concept of the physics of the real world because of their microscopic state we ourselfs could have no concept of what is actually real.

    An example of what I mean about programming is we could possibly be a vitual reality of some super-intelligent race. Everything we percieve and are thinking right now is programmed into some type of computer. We are even programed to think, and to actually "think" that we think (lol). When in actual fact everything we are doing now and do in the future is scripted by a extremely complex program. And the thing is in the end we will never ever really know because there is no way to falsify something like that.

    I have to say it would be interesting if in the future we ourselfs can actually create a vitual reality in which the subjects of the reality genuinely think that they're alive and thinking.


    Edit: And after that, are they considered life? Does it suddenly become unethical to turn off that virtual reality because the subjects inside have conciousness?
    Last edited: Aug 7, 2006
  11. Aug 8, 2006 #10
    Reality is. Objective reality is but one form of reality.

    The mental image of the objective candy bar is another form of reality.

    If reality were only in our mind, would our mind not yet be real?

    If our minds are not real then how could it then hold reality in them? If our minds are not real then nothing can be real, for, how can the unreal sense or effect the real?

    If our minds are real and reality is only in our minds, then would not our minds be also only within our minds?

    You must see the obvious contradictions and paradoxs.

    I, therefore, conclude that "reality being only in our minds" is a logically absurd statement. To me at least this proves that reality is real.

    The possiblity of an envatted brain is real. Our brains are envatted within our skulls and the only physical contact with the outside world is through our physical senses, our bodies.
  12. Aug 8, 2006 #11
    So you've concluded that reality is actually real? Good job.

    But what about our reality. The reality that we live on earth, we're humans. I live in Australia. I'm a person. The world works like this. This could all be an illusion we've been forced upon and even our very selfs might not exist. Just because we can't comphrehend such a situation doesn't mean it's false, that would be a logical fallacy.

    The possibility of an envatted brain/vitual reality are all very REAL posibilities, but such theories cannot be falsified and are therefore equivilent of religion.

    There is nothing hard to comphrehend here. Other then that maybe what we see/hear/feel/smell and think might all just be programmed AI or a brain being stimulated by some mad scientist, producing the illusion we know as life.

    I don't personally believe this, just like I don't believe in anything else that can't be falsified (or have any proof in it). I'm just saying it's very possible what the real reality is like.

    But because we can't know or measure anything about things like that in the end the question is pointless (ignosticism).


    "The real question is not whether machines think but whether men do. The mystery which surrounds a thinking machine already surrounds a thinking man." — B. F. Skinner
    Last edited: Aug 9, 2006
  13. Aug 9, 2006 #12
    If reality is define as; all that is real, all that exists, then that which is not real does not exist.

    If the world and our lives are illusions there must be, exist, something that is inducing these illusions and there must be something that exists that experiences these illusions. If something exist, it is real; therefore, I who am experiencing these illusions exist and that which supplying the illusion exists and is real. If something exists and is real and is not solely of or in our mind, then the statement; "Reality is only in our minds." is false.
  14. Aug 9, 2006 #13
    That's not entirely correct Royce.

    All that is real != all that exists.
    Nor does it follow that that which is not real does not exist.

    "Reality is only in our minds" cannot be a false statement.
  15. Aug 9, 2006 #14

    What's going on here is a power hierarchy.
    We can very well put an ant in a simulated ant hill, and it will live there blissfully.
    However the reality is that it is not a real ant hill.
    Then on the other hand, to the ant, the hill is real, but it's not a real one compared to the other real ones out there.

    So the question then becomes, is our world unique, or is it a simulated one?
    If one can compare our world to other worlds, that are analogous to ours, but not a simulation, are we being trapped?
    Is it real?

    Ultimately, there should be a way for us to find out if we are inside a simulation.
    The world that runs our simulation cannot be entirely different from our own, so in theory we should be able to escape.

    The problem is that the power hierarchy is infinitely regressive, that is to say, anything that exists, even god, can always ask himself "am i inside a simulation?"

    What this means exactly I'm not sure, but if there truly is no way of falsifying it..
  16. Aug 9, 2006 #15


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    I assume programmed is a loosely used term here that basically implies pre-determinism. That is, our consciousness and our actions are just a cause-effect relationship of mechanical, chemical, an electrical processes.

    As for the OP, I think there is a reality, but our experience and observation of that reality is cropped and skewed. It is limited by our most deeply rooted assumptions and our biological (and technological) ability to sense 'reality'. So our perception of reality may be very different from reality itself. This doesn't, however, make use 'safe' from reality.

    I still think, however, that terms like "my reality" are valid, as long as you realize that 'your reality' can influence and be influenced by both other singular relaities and all realities as a collective reality, one of those singular realities being the physical 'laws' of the universe (which we have changed, and been changed by ever since we became curious about them)
  17. Aug 9, 2006 #16
    I think that it is axiomatic that if something exists, it is real. If something does not exist then it is not real.

    The reverse is also true, if something is real then it exists and if something is not real then it does not exist.

    Therefore, all that exist is real and reality is all that exist.

    To repeat my position,

    If reality is only in our minds, our minds then must exist and be real.

    If our minds exist and are real then our minds must be part of reality.

    Therefore in order for "Reality is only in our minds" to be true, our minds must only be in our minds. This is an logically absurd statement and therefore, cannot be true.

    It is a thruth that a thing or object cannot contain or be a part of itself.

    Aside, to address a previous statement made here.

    Regardless of the validity or truth of our experiences, we our something like us must exist to do the experiencing whether real, vertual or total illusion. That which is experiencing must exist to experience anything and therefore, is real. I experience what I take to be reality.
    I therefore exist and am real.

    In other words; I experience; therefore, I am.

    This is the same as; "I think; therefore, I am.
  18. Aug 9, 2006 #17
    imo that's just fancy wording.

    The truth is that there is a possibility that our world is generated or simulated, by something other than reality itself.
    There is a slight chance that we are indeed in another world, that we have been trapped and made prisoners of, and that our world is generated to hide us from the truth.

    While that is extremely melodramatic, it may be.

    Also I do not follow your proposition that all that exists must be real.
    "Real" is by definition relative to the observer, and it is also relative to how much knowledge you have.
    If somehow a person on earth found a way to travel out of the universe, and into the universe where he had been trapped, what is "real" is suddenly changed.

    If you assume that everything and anything, in any dimension or universe is real, then that's a false position in your statement, because you say "Therefore in order for "Reality is only in our minds" to be true, our minds must only be in our minds. ", which would be false if we were indeed trapped in a matrix like universe computer.
    This is because 1. the universe would only be in our minds and 2. it would not be a part of itself.

    I think I got that right anyway.
  19. Aug 9, 2006 #18
    Royce has it right if we agree with this logical sequence that starts with an axiomatic concept:

    1. existence exists
    2. reality is that which exists
    3. minds are real
    4. things not minds are real
    5. reality cannot be only in minds
  20. Aug 10, 2006 #19
    If this is some funny wordplay on the fact that he said "only" please stop me now. If that's not the case I offer a serious explanation below.

    It just doesn't work that way from my point of view.

    The problem is you haven't defined "reality" as I see it.
    If my proposition that we are inside a computer simulation is true, then your sequence is only true if we agree that the world the computer simulation is IN, is a part of reality.

    But this depends on the conscious being inside the simulation, from his point of view there only exists reality.
    However, if there were several realities, all contained in several computer simulations, and then one real world which is NOT inside a computer simulation, then COMPARED to the "real" real world, the computer simulation wouldn't be real, but ONLY to those who knew about the other worlds existence.

    What this means is that in your sequence you need to define "reality."
  21. Aug 10, 2006 #20
    Even if you agree that everything that is real exists and vice versa that still doesn't mean that we/our minds/etc. are real and exist. You could easily experience things that are non-real. Even your mind can be non-real or non-existant.

    The only proof for our minds existing you've given is based off the OPs question, which you yourself disproved.

    Now, -OUR- reality could be in a computer, and that would be "real" to us. But in a genuine sense of what is -actually- real our world in the computer would not be real.

    Edit: Also you have to ask is it possible for something to have a "mind" or a "conciousness" in a simulation? And does that count as "existing" despite the fact that you could possibily just be 1s and 0s (and is that any different to how our bodies and brains and minds work anyway?)
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