Lavater, a close associate of Fuseli, produced a multi-volume treatise on the derivation of character from external facial features, like the angle of the nose or the shape of the mouth. Lavater examines portraits of both real and legendary characters and evaluates them in terms of physiognomic principles. 

This portrait of Satan reveals the eighteenth-century desire de desire to rationalize the fantastic.  Satan, who is typically depicted as a hybrid human-beast or monster, is here portrayed as a man whose face conforms to the same physiognomic principles.  

Unlike a human subject , Satan has no actual appearance; therefore, Fuseli depicts him only in terms of his supremely evil character. Lavater criticises Fuseli’s portrait for the “attractiveness” of the chin and upper lip and the nose which “indicates a judicious spirit but should express more malice and rage”.  He commends it for showing Satan as recognizably a fallen angel with “some traces of his former greatness.”

Cathy Dorin