Removing the Head, or Destroying the Brain: Objections
“If humans have feelings and p-zombies don’t, can’t you generate entire categories of statements revolving around having feelings or not? Why doesn’t that distinguish the two concepts?”
Because we haven’t yet established that “feelings”, in the way David Chalmers talks about them, are a meaningful concept. If they’re empty symbols, they don’t add any meaning to sentences, and implications that appear to be distinct could actually mean precisely the same thing.
“What if we reject Chalmers’ definition and go with a looser one?”
Not a bad question.
As the Wikipedia article on p-zombies makes clear, there are other definitions of the term than the strict and highly limiting one Chalmers uses. A broader and weaker definition wouldn’t be vulnerable to the specific flaw that makes Chalmers’ obvious nonsense.
So what if we consider two beings that are initially identical physically, or can be put in equivalent physical states, but behave differently? What if there’s something “nonphysical” that causes them to be different even if they should be exactly the same according to physics?
There are still problems, there.
First, we need to always remember to distinguish between our ideas about how the universe acts (which we call ‘physics’), and how the universe actually does act (which we also call ‘physics’). If a normal human and a p-z look the same, and our understanding says they should be the same, but they don’t act the same, then our understanding is wrong. Physics is never wrong. Physics is never wrong. If it’s either you or the universe, it’s you.
Next problem: if there’s some supposedly nonphysical thing that influences your behavior, how does it interface with the rest of you? Your behaviors are physical. If one of the causes of those behaviors is nonphysical, there’s some point of interaction between the ‘physical’ and ‘nonphysical’ things. Tracing causality backwards from the action, there has to be some boundary that the causal links cross. Once that’s been identified, we can construct a model of the behaviors that encompasses both sides of the boundary – and once we’ve done that, what grounds do we have for excluding part of the system from our understanding of physics?
Because scientific understanding is open-ended and revisable, there’s no way to establish a partition within it. Postulate a new phenomenon, and you’re speculating about physics.
It’s not a coincidence that ‘immaterial’ means both something that is not made of matter, and something that isn’t relevant. Nor it is a coincidence that ‘matter’ means both a substance and a thing that makes a difference and is relevant. You can postulate a soul or spirit all you like – and I acknowledge that it is conceivable that human behavior requires phenomena beyond our current understanding – but it’s always a material and physical thing, even if it’s some freaky energy being.
If you have any further questions or comments, feel free to post them.