June 1972
A Note on the El Greco Fallacy:
Does It Apply to Methods of Studying Perception?
J. J. Gibson, Cornell University
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In explanation of the fact that El Greco painted saints as elongated in height (and supposedly even ordinary persons and objects) it has been suggested that he suffered from astigmatism which caused his retinal images to be vertically narrower than they should be. Therefore his perceptions of persons and things were elongated, that is, he saw things thinner than they really were, and this explains why his paintings of persons and things were elongated.
The fallacy in the above explanation is, of course, that if El Greco had seen the shapes of objects as thinner than they really were he would have seen the shapes in his paintings as thinner than they really were, and to the same extent, painted shape would have to have the same proportions as the physical shape in order for it to be a representation. Note that the reference to the retinal image and its supposed optical distortion due to astigmatism is actually a red herring; the real fallacy inheres in any line systematic error-tendency in perceiving, i.e. a constant error.
But note that we do in fact take the drawing that a perceiver makes of an object as an indicator of his perception of that object-as an index of his “phenomenal” object. By using the method of reproduction, or an equivalent psychophysical method, the investigator is supposed to be able to compare the physical object with the phenomenal object and to measure any discrepancy between the two.
For example, the geometrical, optical illusions are supposed to exemplify the fact of a systematic discrepancy between certain physical figures and the corresponding phenomenal figures. The Gestalt psychologists have taken the illusions to be expressions of the “laws of organization” that are supposed to govern visual perception. In a book called Struktur and Metnik figural-optischer Wahrnehmung (1952) E. Rausch, a student of Metzger, has measured the “tendency toward orthogonality” in the perceiving of parallelograms, and has actually displayed an illustration of a standard stimulus-figure with the average phenomenal figure superimposed on it. The latter differs in angle of tilt and in altitude, having changed in the direction of “good figure”. Is this legitimate?
The question is whether or not this method, and perhaps other uses of the method of reproduction, entails a form of the El Greco fallacy. We have probably been wrong in assuming that systematic errors in drawing can be taken as evidence for systematic errors in perceiving. Probably a drawing is not psychophysically isomorphic with the phenomenal figure we are trying to investigate. If this is so, how shouldwe investigate visual perception by experimental methods? What does a drawing of an object by a perceiver indicate about his perception of that object? And is there any categorical difference between drawing “from life” (i.e. with the object and the picture in the same field of view) and drawing “from memory” (e.g. when the object is not in the same field of view as the picture)?