"bombast and fustian, which Mr Locke's blind man would not have grossly erred in likening to the sound of a trumpet"
John Locke
Public DomainJohn Locke - Credit: US Library of Congress

Molyneux's problem is a thought experiment, concerning immediate perception and blindness.  It was formulated by philosopher William Molyneux, whose wife was born blind, and posed to John Locke Molyneux argued that, if a man born blind relied on touch to tell the differences between shapes such as spheres and cubes, he would not be able to distinguish those objects by sight alone if he could suddenly see, since there would be no immediate link between his tactile experience and his visual understanding.  Locke agreed, in An Essay Concerning Human Understanding, that the blind man, at first sight, would not be able with certainty to say which was the globe or the cube on the basis of sight alone, but could name them correctly by his touch.