3 ms·

So, what is a red visual experience? Is it the reflective surface of the red-looking object? Is it photons around 700 nanometers wavelength? Is it the electrons

So, what is a red visual experience? Is it the reflective surface of the red-looking object? Is it photons around 700 nanometers wavelength? Is it the electrons traveling to the visual cortex from the eyes? Is it the neural activity in the visual cortex? Is it the symphony of different brain regions brining it all together into a visual experience? Is this the exact symphony that plays in my brain that plays in yours when we look at the same red object? What about when you dream of a red object?

geofft 6y ago
I'd argue that the question isn't well-defined - same as asking whether your experience of counting to five is the same as mine. There is no "experience" of seeing red beyond the simple fact of perceiving 700nm-wavelength light. It is no more possible for me to experience as blue what you experience as red, and vice versa, as for me to experience as 3 what you experience as 2. If I experienced it as 3, that is, one less than 4, it would actually be 3. When I dream of three objects, I experience them just like you would. I don't see why dreaming of a red object would be any different.
- goatlover 6y ago
  > I'd argue that the question isn't well-defined - same as asking whether your experience of counting to five is the same as mine. There is no "experience" of seeing red beyond the simple fact of perceiving 700nm-wavelength light. If your brain can detect 700nm-wavelength light without you having a conscious experience of red, then there certainly is a question. Also, dreaming of red is not perceiving red, since there is no 700nm light. This is why you can't just simply reduce an experience to the stimulus. > It is no more possible for me to experience as blue what you experience as red, and vice versa, as for me to experience as 3 what you experience as 2. If I experienced it as 3, that is, one less than 4, it would actually be 3. When I dream of three objects, I experience them just like you would. I don't see why dreaming of a red object would be any different. The question isn't about the quality of your subjective experiences, it's about whether the pattern of neurons firing would necessarily be the same between people. If not, then you can't simply reduced subjective experiences to brain states. This has been a long standing objecting to the identity theory of mind.
  - geofft 6y ago
    I am not reducing an experience to the stimulus. I am simply reducing its identity to "that experience which is correlated with this stimulus." My brain can detect three items without me having a conscious experience of three, and I can dream of three items without three items existing. I am simply saying that - whatever it is - your brain also has some experience it correlates with the stimulus of three, and there is no meaningful way to compare or contrast that experience with my brain's experience beyond noting that they're both correlated with the same stimulus. We think we can imagine, what if my experience of "red" is your experience of "blue," and vice versa? But that's as meaningful as asking, what if my experience of "two" is your experience of "three," and vice versa? > it's about whether the pattern of neurons firing would necessarily be the same between people Nothing in my argument has anything to do with patterns of neurons firing or even with the existence of brains themselves. Perhaps my "red" neurons are in one place and your "red" neurons are in another place, sure, whatever. Why should that mean that our experiences are different? I mean, certainly, the neurons themselves are not the same. Your neurons don't fire when I see red, or vice versa. But that's not enough to settle anything.
    - goatlover 6y ago
      > I mean, certainly, the neurons themselves are not the same. Your neurons don't fire when I see red, or vice versa. But that's not enough to settle anything. Correct, other than it makes an identity theory of mind problematic. > Why should that mean that our experiences are different? That's not my objection. You stated in the previous post: > There is no "experience" of seeing red beyond the simple fact of perceiving 700nm-wavelength light. I'm objecting to attempts to reduce experience to its physical substrate and then say there's nothing more to the matter. But there is if the reduction doesn't work. And it doesn't in this case, because there are red visual experiences which are not perceptual. Dreams, memories, visualizations and hallucinations can all contain red visual experiences in the absence of 700nm photons. So can directly stimulating the right neurons with a magnet or electrodes in the brain via surgery. This leaves the hard problem intact.
      - geofft 6y ago

geofft 6y ago

I'd argue that the question isn't well-defined - same as asking whether your experience of counting to five is the same as mine. There is no "experience" of seeing red beyond the simple fact of perceiving 700nm-wavelength light. It is no more possible for me to experience as blue what you experience as red, and vice versa, as for me to experience as 3 what you experience as 2. If I experienced it as 3, that is, one less than 4, it would actually be 3. When I dream of three objects, I experience them just like you would. I don't see why dreaming of a red object would be any different.

goatlover 6y ago
> I'd argue that the question isn't well-defined - same as asking whether your experience of counting to five is the same as mine. There is no "experience" of seeing red beyond the simple fact of perceiving 700nm-wavelength light. If your brain can detect 700nm-wavelength light without you having a conscious experience of red, then there certainly is a question. Also, dreaming of red is not perceiving red, since there is no 700nm light. This is why you can't just simply reduce an experience to the stimulus. > It is no more possible for me to experience as blue what you experience as red, and vice versa, as for me to experience as 3 what you experience as 2. If I experienced it as 3, that is, one less than 4, it would actually be 3. When I dream of three objects, I experience them just like you would. I don't see why dreaming of a red object would be any different. The question isn't about the quality of your subjective experiences, it's about whether the pattern of neurons firing would necessarily be the same between people. If not, then you can't simply reduced subjective experiences to brain states. This has been a long standing objecting to the identity theory of mind.
- geofft 6y ago
  I am not reducing an experience to the stimulus. I am simply reducing its identity to "that experience which is correlated with this stimulus." My brain can detect three items without me having a conscious experience of three, and I can dream of three items without three items existing. I am simply saying that - whatever it is - your brain also has some experience it correlates with the stimulus of three, and there is no meaningful way to compare or contrast that experience with my brain's experience beyond noting that they're both correlated with the same stimulus. We think we can imagine, what if my experience of "red" is your experience of "blue," and vice versa? But that's as meaningful as asking, what if my experience of "two" is your experience of "three," and vice versa? > it's about whether the pattern of neurons firing would necessarily be the same between people Nothing in my argument has anything to do with patterns of neurons firing or even with the existence of brains themselves. Perhaps my "red" neurons are in one place and your "red" neurons are in another place, sure, whatever. Why should that mean that our experiences are different? I mean, certainly, the neurons themselves are not the same. Your neurons don't fire when I see red, or vice versa. But that's not enough to settle anything.
  - goatlover 6y ago
    > I mean, certainly, the neurons themselves are not the same. Your neurons don't fire when I see red, or vice versa. But that's not enough to settle anything. Correct, other than it makes an identity theory of mind problematic. > Why should that mean that our experiences are different? That's not my objection. You stated in the previous post: > There is no "experience" of seeing red beyond the simple fact of perceiving 700nm-wavelength light. I'm objecting to attempts to reduce experience to its physical substrate and then say there's nothing more to the matter. But there is if the reduction doesn't work. And it doesn't in this case, because there are red visual experiences which are not perceptual. Dreams, memories, visualizations and hallucinations can all contain red visual experiences in the absence of 700nm photons. So can directly stimulating the right neurons with a magnet or electrodes in the brain via surgery. This leaves the hard problem intact.
    - geofft 6y ago