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MarsColony_in10years comments on GAZP vs. GLUT - Less Wrong

33 Post author: Eliezer_Yudkowsky 07 April 2008 01:51AM

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Comment author: MarsColony_in10years 23 March 2015 02:00:31AM 1 point [-]

Are you arguing that you don't know if you are conscious because you can't be sure that the consciousness you experience and observe matches the consciousness other people claim to experience and observe?

I would argue that the word "red" is poorly defined, since it predates a modern understanding of light. For the purposes of discussion, we might define an object as "red" if the majority of the energy of the visible spectrum (430-790nm) light it reflects or otherwise emits (under uniform illumination across the visible spectrum) has a wavelength between 620 and 750 nm.

But you say this:

f I were to instead be puzzled about "red", you couldn't describe being red to me, but you could at least show me examples of things that are all red.

That may have been true at some point in history, but today I can describe being red to you in great detail, as I did above. Before we had that knowledge, though, we had less strong evidence that we were talking about the same thing, but there was still evidence. Without knowing about photons, it would still seem unlikely that we were talking bout different "reds". Occam's razor would favor a single "red" property or set of properties over something that appeared different to different people based on some complex set of rules. The counter-evidence is colorblindness, of course, but the complexity added by having to claim that some people have eye problems is significantly less than the complexity that would be added by the theory that each person has their own version of red.

I would argue that we have a similar level of knowledge about consciousness, which is further hindered, as you point out, that we can only observe our own consciousness with high fidelity. To observe other people's consciousnesses, we have to examine the things they say and write about their own consciousness. It's a bit like observing the sun, and observing the stars, and trying to deduce whether the sun is a star.

Different cultures seem to have independently come up with similar sounding ideas about consciousness, so it seems like most people are more or less talking about the same sort of thing. I'm sure there are minute differences, just as there are different shades of red, and different classifications of stars. After all, the atoms and neurons in our brains are all configured slightly differently, so it would be surprising if our consciousnesses were exactly identical, neuron for neuron. Then again, it would also be surprising if our sun was exactly the same as some other star, atom for atom. But that's why we use words like "star", "dog", "red" and even "consciousness" to refer to entire classes of things. In this case, "consciousness" refers to the sensation of existing, and the thing that causes us to talk about consciousness. That's not a full definition, but it's a start. We'll have to wait on neuroscience, or perhaps AI research, before we can get a more precise definition.

Comment author: Jiro 23 March 2015 03:31:41AM *  0 points [-]

Are you arguing that you don't know if you are conscious because you can't be sure that the consciousness you experience and observe matches the consciousness other people claim to experience and observe?

Sort of, but not quite.

In the case of "red", I can't be sure that someone's mental sensation when seeing red is the same as my mental sensation when seeing red. They're private, after all. But I can at least be fairly sure that these sensations, however different they may be privately, still point to the same set of things. They are operationally the same. Since my perceptions of red correlate with the other person's perceptions of red, it makes sense to conclude (with less than perfect certainty) that red objects have something in common with each other--that is, that redness is a natural category.

But I can't apply this to consciousness. There are no consciousnesses that we can both see--we can each see at most one, and we can never see the same one that the other can. So the factor that leads me to conclude that redness is a natural category is absent for consciousness.

Different cultures seem to have independently come up with similar sounding ideas about consciousness

Have they? Different cultures have come up with similar sounding ideas on how to conclude that something has consciousness, but they (or their members) cannot ever make direct observations of two consciousnesses and say that they observe similarities between them. So the example of different cultures agreeing only lets us be pretty sure that "consciousness-labelled-observed-behavior" is a real thing, but not that one person's direct observation of their own consciousness is the same as another person's direct observation.

Comment author: MarsColony_in10years 25 March 2015 04:52:03AM *  0 points [-]

Ah, so you were talking about the possible mismatch between our perceptions of the redness of red. I could try to guess at a technical answer, since it would be highly immoral to experiment with actual people. I'm not sure it would make any difference to the consciousness argument, though.

It sounds like you do experience some sort of sensation of existing, but that you don't talk about this sensation with words like "consciousness", or anything else, because you can't draw a logical link between different people's consciousnesses to show that they are the same thing.

But I'm not talking about formal logic. I'd agree with you that given what we know, we can't deduce that everyone is talking about the same "consciousness". However, we have tools in our bag besides just formal logic. One such tool is Bayes' theorem. Do you really prescribe less than a 50% probability to the hypothesis that our ideas of "consciousness" are similar, rather than entirely random things? Maybe it isn't above a 95% certainty, or 99.9%, or whatever arbitrary threshold you would choose before you can safely say that you "know" something.

Personally, I would assign a low probability to the idea that our consciousnesses are identical, but a quite high probability to the idea that they are at least similar in nature. People seem to talk about consciousness in much different ways than they talk about potatoes or space-time. There are enough differences in the rest of our brains that I would be surprised if consciousnesses were identical, but there are still patterns that are similar between most human brains. It strikes me as an unsolved but bounded question, rather than an unknowable one.