Tuesday, November 09, 2010

Zombies are real

I refer here not to the brain-eating horror-movie staple but rather philosophical zombies, beings that are "indistinguishable from ... normal human[s] except that [they] lack conscious experience, qualia, or sentience." Here is a fascinating account of Tom Lubbock, an art critic with a brain tumor that occasionally renders him essentially a philosophical zombie:

My speech is now becoming a radical problem. Sometimes, for a short period, and suddenly, I find that I no longer know what I am saying, but I still go on talking and talking sense – like an inspired sibyl or a medium. The voice works automatically, fluently, subconsciously, through habit or practice. The words would need to be looked up, if I could recognise their spelling. But I can feel at least that my speaking is correct and I am aware that my words and phrases are familiar and appropriate.

Likewise, I can hear others' words and accept them as meaningful, without being able to repeat or paraphrase or interpret their meaning, though I can perhaps reply sensibly or at least act sensibly in reply. At a particular subconscious level, speech is functioning. Consciously, I can't spell some words, I don't know what they mean, I can't recite their phonemes. All I can recognise is the phatic role of my words, their tone.

To explain. One can have quite extended conversations more or less on autopilot.


Don Geddis said...

Another possible interpretation is that the tumor is splitting his brain into more than one mind, and part of him happens to have no introspective access to what the other part is doing. Just because "he" doesn't have conscious access to the conversation, doesn't mean that the speaker of conversation necessarily lacks that access (or the associated qualia).

We've seen this before with split-brain patients. It's easy to run experiments where you provide information to one hemisphere but not the other, demand action by the first hemisphere, but then ask the second hemisphere to explain that action. The rationalizations are wonderfully amusing.

Ron said...

This seems different to me. Lubbock isn't rationalizing. Quite the opposite: he is explicitly reporting being unable to account for the actions being performed by part of his mind that he no longer has conscious access to.

Ron said...

BTW, you don't need to do split-brain experiments to get interesting rationalizations out of people:


Don Geddis said...

The relevance of the example is that we already know that multiple conscious minds can coexist inside a single human brain. So interpreting Lubbock's report of his experience is challenging.

In any case, I read the original article after my previous comment. I've got a new interpretation. Lubbock talked about, not being able to have extended conversations in depth (without consciousness), but instead only about making it through highly scripted interactions (like buying an item at a store).

I can believe that common scripted social situations could be so programmed and automatic, that consciousness is not required. Somebody says "how are you today?" and you answer "fine!", without even polling your internal state to figure out how you really feel, or accessing your memory and prediction of the near future to really evaluate how your day is going. You just automatically say "fine!"

I can program a computer to survive those scripted interactions too, with no particular need for consciousness.