Aesthetics (also spelled æsthetics and esthetics also known in Greek as Αισθητική) is a branch of philosophy dealing with the nature of art, beauty, and taste, with the creation and appreciation of beauty. It is more scientifically defined as the study of sensory or sensori-emotional values, sometimes called judgments of sentiment and taste. More broadly, scholars in the field define aesthetics as "critical reflection on art, culture and nature."
More specific aesthetic theory, often with practical implications, relating to a particular branch of the arts is divided into areas of aesthetics such as art theory, literary theory, film theory and music theory. An example from art theory is aesthetic theory as a set of principles underlying the work of a particular artist or artistic movement: such as the Cubist aesthetic.
If an item is considered to be aesthetic depends highly upon the person creating it and the person experiencing it. This holds true even when their species are the same. It is more common that an item is unaesthetic between species (e.g. Eric's reaction to Yokuta music).