The development of the visual arts during the twentieth century blurred the boundaries between what is, and what is not, considered art. Arthur Danto proposed an aesthetic theory that would allow us to redefine the boundaries of art. In this article, I examine two of the most problematic aspects of Danto’s theory: the excessive weight he gives to the concept of mimesis, and his teleological conception of the history of art. If these two elements are attenuated, the theory loses most of its explanatory power. In the last two sections of the article, I argue that the artworld to which Danto gives a central role in the demarcation problem is only a by-product of the conditions that determine the nature of art in general.