aesthetics :
1. the branch of philosophy dealing with such notions as the beautiful, the ugly, the sublime, the comic, etc., as applicable to the fine arts, with a view to establishing the meaning and validity of critical judgments concerning works of art, and the principles underlying or justifying such judgments.
2. the study of the mind and emotions in relation to the sense of beauty.

I'm not really sure how much science is involved. Like eo mentioned, "the cognition people are making it up as they go along."