 John Hyman and Catherine Abell have proposed different theories of depiction in which the idea of resemblance plays a significant role. Hyman rejects the theory that pictures are iconic signs (2012: 127), but he claims that there is a strict and invariable relationship between the shapes and colours on a picture’s surface and the shapes and colours of the objects it represents. Hyman’s theory depends on Gottlob Frege’s distinction between sense and reference (see §3.2 of the  entry on  Frege).  Taking one of Frege’s own examples, the phrases “the morning star” and “the evening star” have the same reference, but different senses, or modes of presentation. Both phrases refer to one and the same object, the planet Venus, but they describe or present it as a star that is visible at different times of day. Similarly, two portraits of the same individual may present him as dark-haired and seated, wearing a black smock  (Kramskoy’s 1873 portrait of Tolstoy),  or as grey-haired and standing, wearing a white smock  (Repin’s 1901 portrait).  They portray (refer to) the same individual, but they present him differently (they differ in sense). The distinction matters, Hyman argues, because resemblances do not explain a picture’s reference, they explain its sense. (The claim that A depicts B if and only if A appreciably resembles B, which Goodman criticizes, is about depiction qua portrayal, i.e., pictorial reference, not sense.)