Art is visible. However, everything one sees is filtered through certain conditions, some of them historical, and others, natural. The historical conditions include the material which is used --oil, color1s, and the canvas; second, a certain style. There can be a general style, for example, the style of Impressionism, or a particular style, for example, the individual ways in which two painters, both impressionists, paint. The natural conditions include certain unchanging psychological laws of sight, for instance, the effects of color1s or optical illusions. The conditions of art are nothing but a particular way of interpreting reality. To understand this, one can examine the difference between the classical Greek and the classical Egyptian styles. For the Greeks, the reality of the visible was given by the perspective and the situation in which the object appears; for that reason they presented a person in his individual movements. For the Egyptians, however, this was only the appearance of a brief moment, which, according to their beliefs, was not real. Therefore, the Egyptians searched for the permanent essence and the typical character in their depiction of an object. For the Egyptians, Greek art was an illusion; for the Greeks, on the other hand, Egyptian art was unrealistic constructivism. The way in which reality appears in art must not be regarded on its own. It is affected by many other systems of recognizing reality, including the political, religious, economic, intellectual, and social -- in short, all the phenomena of human life. Moreover, art is always of a certain epoch  ,with its particular conception of reality. Thus, when discussing, for example, the art of ancient myth, of medieval Christianity, or that of the technological age, one must be aware that myth, Christianity, or technology was the most outstanding feature of the epoch. It is paradoxical  to understand art as some kind of copy of the fields of experience connected with it. So, for example, it is meaningless for the work of art to be compared with the landscape, which served the artist as his model. Even if the artist had tried to make what he painted as similar as possible to the model he used, the landscape which he saw is only the matter from which something completely different emerges since he has submitted his view to the conditions of art: namely to the material used (color1s, canvas, etc.), to his style, and even to the fact that he paints on a flat surface. Thus one must contemplate  a work of art by itself. Even if it is connected to other fields of experience it nevertheless displays something unique which appears in that piece of art and there alone. Why did the Egyptians search for the permanent essence of an object?
Egyptian art was thought to be unrealistic constructivism. They should present a person in his individual movements. The reality of the visible was only the presence of an instant. The appearance of the object features largely in the reality.