we get: 1a) imagine a microphysical duplicate of our world that’s lacking consciousness
Right, that’s the claim. I explain why I don’t think it’s question-begging here and here
How can can you perform that step unless you’ve first defined consciousness as something that’s other-than-physical?
If the “consciousness” to be imagined were something we could point to and measure, then it would be a physical property, and would thus be duplicated in our imagining. Conversely, if it is not something that we can point to and measure, then where does it exist, except in our imagination?
The logical error in the zombie argument comes from failing to realize that the mental models we build in our minds do not include a term for the mind that is building the model. When I think, “Richard is conscious”, I am describing a property of my map of the world, not a property of the world. “Conscious” is a label that I apply, to describe a collection of physical properties.
If I choose to then imagine that “Zombie Richard is not conscious”, then I am saying, “Zombie Richard has all the same properties, but is not conscious.” I can imagine this in a non-contradictory way, because “conscious” is just a label in my brain, which I can choose to apply or not apply.
All this is fine so far, until I try to apply the results of this model to the outside world, which contains no label “conscious” in the first place. The label “conscious” (like “sound” in the famous tree-forest-hearing question) is strictly something tacked on to the physical events to describe a common grouping.
In other words, my in-brain model is richer than the physical world—I can imagine things that do not correspond to the world, without contradiction in that more-expressive model.
For example, I can label Charlie Sheen as “brilliant” or “lunatic”, and ascribe these properties to the exact same behaviors. I can imagine a world in which he is a genius, and one in which he is an idiot, and yet, he remains exactly the same and does the same things. I can do this because it’s just my label—my opinion—that changes from one world to the other.
The zombie world is no different: in one world, you have the opinion that I’m conscious, and in the other, you have the opinion that I’m not. It’s your failure to notice that “conscious” is an opinion or judgment—specifically, your opinion or judgment—that makes it appear as though it is proving something more profound than the proposition that people can hold contradictory opinions about the same thing.
If you map the argument from your imagination to the real world, then you can imagine/opine that people are conscious or zombies, while the physical world remains the same. This isn’t contradictory, because it’s just an opinion, and you can change your opinion whenever you like.
The reason the zombie world doesn’t then work as an argument for non-materialism, is that it cheats by dropping out the part where the person doing the experiment is the one holding the opinion of consciousness. In your imagined world, you are implicitly holding the opinion, then when you switch to thinking about the real world, you’re ignoring the part that it’s still just you, holding an opinion about something.
How can can you perform that step unless you’ve first defined consciousness as something that’s other-than-physical?
If the “consciousness” to be imagined were something we could point to and measure, then it would be a physical property, and would thus be duplicated in our imagining. Conversely, if it is not something that we can point to and measure, then where does it exist, except in our imagination?
The logical error in the zombie argument comes from failing to realize that the mental models we build in our minds do not include a term for the mind that is building the model. When I think, “Richard is conscious”, I am describing a property of my map of the world, not a property of the world. “Conscious” is a label that I apply, to describe a collection of physical properties.
If I choose to then imagine that “Zombie Richard is not conscious”, then I am saying, “Zombie Richard has all the same properties, but is not conscious.” I can imagine this in a non-contradictory way, because “conscious” is just a label in my brain, which I can choose to apply or not apply.
All this is fine so far, until I try to apply the results of this model to the outside world, which contains no label “conscious” in the first place. The label “conscious” (like “sound” in the famous tree-forest-hearing question) is strictly something tacked on to the physical events to describe a common grouping.
In other words, my in-brain model is richer than the physical world—I can imagine things that do not correspond to the world, without contradiction in that more-expressive model.
For example, I can label Charlie Sheen as “brilliant” or “lunatic”, and ascribe these properties to the exact same behaviors. I can imagine a world in which he is a genius, and one in which he is an idiot, and yet, he remains exactly the same and does the same things. I can do this because it’s just my label—my opinion—that changes from one world to the other.
The zombie world is no different: in one world, you have the opinion that I’m conscious, and in the other, you have the opinion that I’m not. It’s your failure to notice that “conscious” is an opinion or judgment—specifically, your opinion or judgment—that makes it appear as though it is proving something more profound than the proposition that people can hold contradictory opinions about the same thing.
If you map the argument from your imagination to the real world, then you can imagine/opine that people are conscious or zombies, while the physical world remains the same. This isn’t contradictory, because it’s just an opinion, and you can change your opinion whenever you like.
The reason the zombie world doesn’t then work as an argument for non-materialism, is that it cheats by dropping out the part where the person doing the experiment is the one holding the opinion of consciousness. In your imagined world, you are implicitly holding the opinion, then when you switch to thinking about the real world, you’re ignoring the part that it’s still just you, holding an opinion about something.