Molyneux's Question: Vision, Touch, and the Philosophy of Perception (review)

BOOK REVIEWS 255 that sensitive knowledge involves the perception of the agreement between an "idea of actual sensation" and the "idea of actual existence of something without me that causes that sensation." The passivity of mind in receiving such ideas and the mind's inability to create simple ideas is the guarantee that such ideas come from the extra-mental world. From this account it follows that there can be no honest scepticism of the existence of particular physical things, though such scepticism may occur about what a thing is. The line of argument in Squadrito's book seems reasonable, particularly since Locke was aware of the kinds of objections that he himself had raised against Malebranche's view that we are acquainted only with ideas and his explicit reply to Stillingfleet on this issue. Squadrito's argument is not without difficulty. In intuitive knowledge one perceives agreement /disagreement between ideas; in demonstration one perceives agreement/disagreement between propositions; but in sensitive knowledge as Squadrito accounts for it the perception of agreement/disagreement is between an idea (hard, yellow, smooth) and what seems to be a proposition ("There is something outside me which causes such ideas"). How two such things can be said to agree needs exploration. All in all, the book is worth reading; it demands that one assess his understanding of Locke on the points indicated. The reader may be confused by the fact that the footnotes for Chapter I are listed as the footnotes for Chapter II, the footnotes for Chapter II are listed as the footnotes for Chapter III, and so on. HENRY G. VAN LEEUWEN Hanover College Michael J. Morgan. Molyneux's Question: Vision, Touch, and the Philosophy of Perception . New York: Cambridge University Press, 1977. Pp. vii + 213. $15.95. In correspondence to his friend Locke, William Molyneux's question, reproduced in the second edition of Locke's Essay Concerning Human Understanding, was whether or not a man born blind, on recovering his sight, could, without touching them, correctly name a cube and a sphere which had been placed in his line of vision. It is often thought, M. J. Morgan says in Molyneux's Question, that the discipline of psychology had its origins in the eighteenth century when philosophers began asking questions about the perception of blind people. The stated purpose of Morgan's book is to show the relationship between concerns of Locke and those eighteenth-century philosophers in answering Molyneux's question, and certain concerns of present day psychologists in their work on perception. On the topic of perception, the concerns of Locke and those eighteenth-century philosophers whom Morgan discusses in some detail--Berkeley, Condillac, Diderot, and Thomas Reid--are related in at least two important respects to the concerns of present day psychologists working on perception. First, they are concerned about what the role of experience is in perception; second, they are concerned about what the relationship is between visual and haptic (tactile) perception. In addition, Morgan finds similarities between historical responses to these concerns and responses to these concerns by present day psychologists. Responses of present day psychologists are similar to historical resp 'onses that stressed the importance of the active aspect of experience in perception (empiricists), and are similar to others which supported general ideas or concepts as the basis of the relationship between visual and haptic perception (nativists). For different reasons, Locke, Berkeley, and Condillac answered 'Not' to Molyneux's 256 HISTORY OF PHILOSOPHY question whether or not a blind man, on recovering his sight, would be able to name a cube and a sphere. Present day psychologists do not know the answer, Morgan says, to Molyneux's question. He gives several reasons for this. First, serious questions can be raised about whether or not the visual system of the congenitally blind would be in a functioning state. Second, the evidence from studies done on cases of blind people who have received corneal grafts are contradictory. Third, recent data from studies done on animals are also contradictory and insufficient. However, the last ten pages of Molyneux 's Question are devoted to describing a relatively new apparatus, the study of which Morgah believes may provide help for...