In art theory since the Renaissance, the relative merits of different art forms are compared and debated. This opposition is built around a comparison (paragone in Italian) between painting and sculpture. Many authors endeavored to prove the superiority of one form over the other through written treatises.

Painting’s most obvious flaw is its inability to express the third dimension, whereas that third dimension is precisely the raison d'être of sculpture in the round. The imitation of sculpture or architecture using brushstrokes allowed the painter to demonstrate his virtuosity by creating the illusion depth and relief. The painters would particularly strive to imitate bas-reliefs and sometimes even gemstones and cameos. They thus proved that a healthy emulation of classical art was more than a simple matter of historical painting.

This imitation often led to efforts to trick the senses of the observer and generate a certain ambiguity as to which technique was used to produce the object, a genre which has come to be known as trompe-l’œil.

The imitation of marble, bronze, or a cameo is generally achieved using a single color. The third dimensional effect is then created only through use of light and shadow.