Mirror reversals: real and perceived

Abstract

A mirror optically reverses the axis perpendicular to its surface, but apparent reversals (eg right-left) can be seen parallel to the surface. This poses a perceptual problem which Ittelson, Mowafy, and Magid resolved by concluding that an object appears to differ from its mirror image by an apparent reversal along its axis of greatest symmetry. Three papers--two included in this discussion (by Haig and by Morris), and an earlier one by Gregory--that disagree with this conclusion are examined, and arguments advanced in them are shown to be unconvincing. The question of apparent mirror reversals is then discussed in more detail.