<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR><font face="Verdana, Arial" size="2">Originally posted by Louis Swaim:
I must have been speaking from the perspective of World One. Can one cogitate absent a brain?
“I’ll let you be in my dream, if I can be in yours.”
Louis: further to my last posting in reply to yours, I would like to add further, that Karl Popper is of course by no means the only distinguished 20th century philosopher to have criticised strongly the Mind/Brain 'Identity Theory'. The American philosopher Hilary Putnam (born in 1926) has also done so, and I subjoin a summary of his position from the following website: http://www.iep.utm.edu/i/identity.htm
'4. Multiple Realizability
In his 1967 paper, "The Nature of Mental States," Hilary Putnam introduced what is widely considered the most damaging objection to theories of Mind-Brain Type Identity-- indeed, the objection which effectively retired such theories from their privileged position in modern debates concerning the relationship between mind and body. Putnam's argument can be paraphrased as follows: (1) according to the Mind-Brain Type Identity theorist (at least post-Armstrong), for every mental state there is a unique physical-chemical state of the brain such that a life-form can be in that mental state if and only if it is in that physical state. (2) It seems quite plausible to hold, as an empirical hypothesis, that physically possible life-forms can be in the same mental state without having brains in the same unique physical-chemical state. (3) Therefore, it is highly unlikely that the Mind-Brain Type Identity theorist is correct.
In support of the second premise above--the so-called "multiple realizability" hypothesis--Putnam raised the following point: we have good reason to suppose that somewhere in the universe--perhaps on earth, perhaps only in scientific theory (or fiction)--there is a physically possible life-form capable of being in mental state X (e.g., capable of feeling pain) without being in physical-chemical brain state Y (that is, without being in the same physical-chemical brain state correlated with pain in mammals). To follow just one line of thought (advanced by Ned Block and Jerry Fodor in 1972), assuming that the Darwinian doctrine of evolutionary convergence applies to psychology as well as behavior, "psychological similarities across species may often reflect convergent environmental selection rather than underlying physiological similarities." Other empirically verifiable phenomena, such as the plasticity of the brain, also lend support to Putnam's argument against Type Identity. It is important to note, however, that Token Identity theories are fully consistent with the multiple realizability of mental states.' Kind regards, Simon.