"The El Greco fallacy" fallacy.
To what extent does an artist's work represent his or her perceptual world, and to what extent can attributes of his or her work be ascribed to sensory defects? These issues lie at the center of a conjecture more than a century old, which has been termed the El Greco fallacy. The El Greco fallacy posits that the elongation evident in El Greco's art reflects an underlying perceptual elongation of objects caused by astigmatism. The "logical" refutation of this theory argues that any perceptual elongation that El Greco might have experienced as a result of astigmatism would have caused not only his subjects to be elongated but also his canvas. Hence, it should have been unnecessary for him to elongate his paintings to match his perception. This objection is important because it warns us against drawing the erroneous conclusion that an artist's work represents a facsimile of his or her perception. However, an analysis of the effects of astigmatism on the retinal image suggests that this "logical" refutation of the El Greco fallacy promulgates another fallacy--that of astigmatism as a source of a constant perceptual error.