The essay concerns the conceptual definition of aesthetics and particularly of aesthetic experience. With references to Mikel Dufrenne and John Dewey it is argued the phenomenological antecedence and the logical priority of «aesthetics» towards the conceptual field of art. In this theoretical framework the aesthetic experience is interpreted as an intensified experience of the conditions of the common experience. By an analysis of the perceptual dynamic the aesthetic experience is so understood as a beneficial exchange with the environment. As a «knowing how», which preludes every form of «knowing that», the aesthetic experience anticipates cognitive relationships with the world and ethic attitudes. Consequently, it is assumed that there is a necessary connection between the emergence of human being and the genesis of an aesthetic attitude. From a phylogenetic point of view it is finally conjectured that the aesthetic attitude emerges in the human kind as a result of detaching itself of desire from the context of utility that characterizes the relationship between animal aesthetics and sexual selection.