Aesthetics is a branch of philosophy concerned with the nature of beauty. In art, it refers to the pursuit of beauty or good taste in art, rather than the practical, moral or narrative. The aesthetic art movement in the late 19th century focused on pure beauty in art, concentrating on its visual and sensual qualities.
In the 20th century, art theorists such as Ernst Gombrich and Roger Fry began to focus on the experience of art, rather than its visual properties. They argued that our experience of art is shaped by our prior knowledge and expectations, and that meaning in art is not inherent in the work itself, but is created by the viewer.
More recent thinkers such as Nelson Goodman and Arthur Danto have expanded on these ideas, arguing that our understanding of art is constantly evolving, as we learn more about the world and ourselves.