Final answer:
The 'fool the eye' realism in William Harnett's A Smoke Backstage is referred to as trompe l'oeil, a technique that creates the optical illusion that the depicted objects are three-dimensional.
Step-by-step explanation:
The "fool the eye" realism of paintings like William Harnett's A Smoke Backstage is referred to as trompe l'oeil. This French term translates to "fools the eye" and describes an art technique that uses realistic imagery to create the optical illusion that depicted objects exist in three dimensions.
It is closely related to the Photorealism movement, which emerged in the late 1960s and 1970s in the United States and Britain, where the subject matter is portrayed in an extremely detailed and exacting style, often compared to an actual photograph. The Photorealists focused on everyday scenes and rendered them with meticulous detail, capturing the interplay of light and color.