The paper tries to clarify the relationship between aesthetic experience and artworks, as well as between cognition and the pleasures of art. Starting with an analytical distinction between aesthetics and art-theory, I propose a psychologically and phylogenetically grounded description of the mental resources on which aesthetic experience draws. After tracing a tentative phylogeny of the cognitive and affective resources defining aesthetic experience, I distinguish three structural components: (a) a marked inflection towards a costly use of mental resources (characterized by costly signaling, attention-driven cognitive dynamics, perceptual learning, attentional overload and divergent cognitive style); (b) a real-time hedonic calculus evaluating the properties of the attentional processing; (c) a bi-directional feedback between attention and hedonic calculus. Finally, the paper discusses the relationship between cognitive fluency and positive aesthetic experiences, arguing that fluency can explain the aesthetic pleasures of art only in conjunction with a second and opposite source of pleasure: curiosity.