This paper argues that a realistic ontology can be defended regarding aesthetic properties and that aesthetic knowledge can be shown rationally acceptable. In the first part, the author argues that aesthetic realism is a common sense conception and he examines how exactly it conflicts with certain scientific desiderata. In the second part, he surveys some of the ways to eliminate or reduce aesthetic properties and argues that none of these attempts is successful. Finally, he suggests a plausible ontological status for aesthetic properties intended to be partly compatible with our physicalist intuition, but opening the way for a more liberal ontology.