Comparisons of aesthetic valence and of sensory magnitude are subject to similar order effects, indicating an evolved mechanism that sharpens also aesthetic discrimination. As the foundation of pleasantness and aesthetic valence of an object, an optimal level of evoked arousal or, in more recent research, of information load, has been proposed. According to discrepancy theory, this evoked effect is modulated by the object's deviation from the current adaptation level (AL). The AL is built up and updated by pooling recent stimulation. A model based on these concepts is proposed here, and it is illustrated by results of empirical studies by the author's students. For everyday objects such as cars and ladies' clothes, rated beauty was related by a U-shaped function to rated modernity. Minimal beauty occurred for intermediate modernity. For ladies' clothes, this minimum was situated higher on the modernity scale for females and extraverts. As modernity can be seen as the amount of deviation from the AL which represents the usual, this shift could be explained by faster upward adjustment of the AL. In contrast, for paintings the relation between modernity and beauty was inversely U-shaped. This could be due to paintings intrinsically carrying more information than other objects, as indicated by ratings of hard-to-access, with which rated beauty had an inverse U-shaped relation. In a factor-analytic study of preference for 42 paintings four orthogonal factors were extracted, interpreted as High and Low modernity, and High and Low information content. This could yield a rudimentary empirical typology of art.