Over at TSZ Lizzie disagrees with me regarding my conclusions from the zombie thought experiment (see this post). Very briefly, in the zombie post I summarized David Gelernter’s argument from the zombie thought experiment:
If a conscious person and a zombie behave exactly alike, consciousness does not confer a survival advantage on the conscious person. It follows that consciousness is invisible to natural selection, which selects for only those traits that provide a survival advantage. And from this it follows that consciousness cannot be accounted for as the product of natural selection.
Lizzie disagrees. In her post she writes:
What is being startled if not being “conscious” of an alarming signal? What is trying to gain further information, if not a volitional act? What is recognising that information is lacking if not a metacognitive examination of the state of self-knowledge? What is anticipating another’s desires and needs, if not the ability to imagine “what it it is like” to be that person? What is wanting to please or help another person if not the capacity to recognise in another being, the kinds of needs (recharging? servicing?) that mandate your own actions? In other words, what is consciousness, if not these very capacities?
Let’s answer Lizzie’s question using her first example (the reasoning applies to all of her others). To be startled means to be agitated or disturbed suddenly. I can be startled by an unexpected loud noise and jump out of my seat. Zombie Fred would have the same reaction and jump right out of his chair too. Our physical outward actions were be identical. So what is the difference? Simply this. I as a conscious agent would have a subjective reaction to the experience of being startled. I would experience a quale – the surprise of being startled. Zombie Fred would not have a subjective reaction to the experience.
I discussed a similar situation in this post in which I contrasted my experience of a beautiful sunset with that of a computer. I wrote:
Consider a computer to which someone has attached a camera and a spectrometer (an instrument that measures the properties of light). They point the camera at the western horizon and write a program that instructs the computer as follows: “when light conditions are X print out this statement: ‘Oh, what a beautiful sunset.’” Suppose I say “Oh, what a beautiful sunset” at the precise moment the computer is printing out the same statement according to the program. Have the computer and I had the same experience of the sunset? Obviously not. The computer has had no “experience” of the sunset at all. It has no concept of beauty. It cannot experience qualia. It is precisely this subjective experience of the sunset that cannot be accounted for on materialist principles.