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Molyneux problem

DOI: 10.4324/0123456789-DA057-2
Version: v2,  Published online: 2018
Retrieved April 12, 2024, from

Article Summary

The Molyneux problem asks whether a newly sighted person might immediately identify shapes previously known only to touch, like cubes and spheres, by sight alone. Over three centuries ago, the designer, William Molyneux, a Fellow of the Royal Society living in Ireland, conveyed the problem in a series of letters to John Locke. Locke soon published the problem and Molyneux’s own ‘not’ answer, in the second edition of his famous work, An Essay Concerning Human Understanding.

Molyneux reasoned that the newly sighted person would fail for having no way to know that the newly seen shapes were like the felt shapes; the feel of the cube corner would not at all be like the look of the cube corner. Many philosophers have agreed with Molyneux’s ‘not’, arguing either that each sense produces concepts unique to it or that new sensory experiences, like those of newly sighted people, are too primitive for identifying three-dimensional shapes. Additionally, early experiments on subjects who have had cataracts surgically removed seem to confirm Molyneux’s supposition, as the newly sighted do not immediately identify shapes known to them by touch.

More recent empirical experiments on cataract surgery subjects, newborns, and with technological innovations like sensory substitution devices, suggest support for a ‘yes’ answer to the question, inspiring philosophical and psychological accounts of perception that explain how the newly sighted might succeed in recognizing three-dimensional spatial features by sight.

Citing this article:
Glenney, Brian. Molyneux problem, 2018, doi:10.4324/0123456789-DA057-2. Routledge Encyclopedia of Philosophy, Taylor and Francis,
Copyright © 1998-2024 Routledge.

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