Commissurotomy, Consciousness, and Unity of Mind
The author writes:
"Recent pyschological studies of commissurotomy patients have provoked considerable, sometimes wild, speculation by both philosophers and the experimenters themselves. Among neuropsychologists, the prevalent view is that the split-brain patient has two minds. These two minds are taken to exemplify a variety of dichotomies: for example, one is atomistic, analytical, digital, symbolic, discursive; the other, holistic, synthetic, analogic, perceptual, eidetic. Further, it is inferred, there is a similar split in the fundamental cogntive styles of the left and right halves of the intact brain, whether or not they are also counted as separate minds. . . . In this monograph, my primary concern is the number of minds split-brain patients have; the speculations on what types of minds these may be . . .are left for another time. I advocate a conservative assessment of split-brain research: the split-brain patient has one mind and is one person, although he has on occasion a disunified consciousness."
—Barbara Von Eckhardt Klein, Yale University
"This is a superb monograph. It raises the debate on the philosophical issues connected with split-brain research to a much higher level than before.
"That the split brain case is philosophically perplexing is undeniable; a description of the experiments of Sperry and others strikes not only philosophers but philosophy students and laymen as raising significant issues about what it is to have a single mind. The split brain cases have come to play a role in philosophy classes like that of other cases which are about equally puzzling but wholly fictional. Marks' piece is a major advance...It would be a terrific choice for a course on the philosophy of psychology or for a seminar in philosophy or psychology."
—John R. Perry, Stanford University