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摘要

The suggestion that consciousness might be substrate-dependent -in other words, that protoplasmic brains can be conscious but silicon can't - is an example of vitalism, the idea that living things have properties that are inexplicable by the rules of physics and chemistry. This concept has been in retreat since 1828, when Friedrich Woehler made the bodily substance urea from inorganic ammonium cyanate. Given centuries of progress in genetics, biochemistry, neurology and so on, vitalism can only be deemed mysticism. The requirements of consciousness aren't exotic: self-awareness, attention and memory are probably all that are necessary, though integrating these functions may call for ingenuity.