As a discipline, art history is distinguished from art criticism, which is concerned with establishing a relative artistic value upon individual works with respect to others of comparable style, or sanctioning an entire style or movement; and art theory or "philosophy of art", which is concerned with the fundamental nature of art. One branch of this area of study is aesthetics, which includes investigating the enigma of the sublime and determining the essence of beauty. Technically, art history is not these things, because the art historian uses historical method to answer the questions: How did the artist come to create the work?, Who were the patrons?, Who were his or her teachers?, Who was the audience?, Who were his or her disciples?, What historical forces shaped the artist's oeuvre, and how did he or she and the creation, in turn, affect the course of artistic, political, and social events? It is, however, questionable whether many questions of this kind can be answered satisfactorily without also considering basic questions about the nature of art. The current disciplinary gap between art history and the philosophy of art (aesthetics) often hinders this inquiry.