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.