Aesthetics (also spelled æsthetics) is commonly known 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." Aesthetics is a branch of axiology and is closely associated with the philosophy of art.
The term aesthetics 1790-, derives from the German ästhetisch or the French esthétique, both derived from the Greek αισθητικός (aisthetikos) "esthetic-sensitive-sentient", from αίσθηση-αισθάνομαι (aisthese-aisthanomai) "to perceive-feel-sense"
The eighteenth century is critcial in the history of aesthetics and of art criticism in general. It is known that the very term aesthetics was coined at that time, and, at least in the opinion of some historians, the subject matter itself, the “philosophy of art,” was invented in that comparatively recent period and can be applied to earlier phases of Western thought only with reservation. It is also generally agreed that such dominating concepts of modern aesthetics as taste, sentiment, genius, originality, and creative imagination did not assume their definite modern meaning before the eighteenth century. Some scholars have rightly noticed that only the eighteenth century produced a type of literature in which the various arts were compared with each other and discussed on the basis of common principles, whereas up to that period treatises on poetics and rhetoric, on painting and architecture, and on music had represented quite distinct branches of writing and were primarily concerned with technical precepts rather than with general ideas. Finally, at least a few scholars have noticed that the term Art, with a capital A and in its modern sense, and the related term fine arts (Beaux-Arts) originated in all probability in the eighteenth century.
If we take all these facts for granted, we can concentrate instead on a much simpler, and in a sense more fundamental, point that is closely related to the problems so far mentioned: the term Art in the eighteenth century comprises above all the five major arts of painting, sculpture, architecture, music, and poetry. These constitute the irreducible nucleus of the modern system of the arts, on which all modern writers and thinkers of aesthetics seem to agree. On the other hand, certain additional arts are sometimes added to the scheme, but with less regularity, depending on the different views and interests of the authors concerned: gardening, engraving and the decorative arts, the dance, and the theater, sometimes the opera, and finally eloquence and prose literature. This system of the five major arts, which underlies all modern aesthetics and is so familiar to us all, is of comparatively recent origin and did not assume definite shape before the eighteenth century, although it has many ingredients that go back to classical, medieval, and Renaissance thought.