Art
Art is a diverse range of human activities in creating visual, auditory or performing artifacts (artworks), expressing the author's imaginative or technical skill, intended to be appreciated for their beauty or emotional power. In their most general form these activities include the production of works of art, the criticism of art, the study of the history of art, and the aesthetic dissemination of art.
Culture
Culture () is the social behavior and norms found in human societies. Culture is considered a central concept in anthropology, encompassing the range of phenomena that are transmitted through social learning in human societies. Some aspects of human behavior, social practices such as culture, expressive forms such as art, music, dance, ritual, religion, and technologies such as tool usage, cooking, shelter, and clothing are said to be cultural universals, found in all human societies. The concept of material culture covers the physical expressions of culture, such as technology, architecture and art, whereas the immaterial aspects of culture such as principles of social organization (including practices of political organization and social institutions), mythology, philosophy, literature (both written and oral), and science comprise the intangible cultural heritage of a society.
Theory
A theory is a contemplative and rational type of abstract or generalizing thinking, or the results of such thinking. Depending on the context, the results might, for example, include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several related meanings.
Theory
I firmly believe people have hitherto been a great deal too much taken up about doctrine and far too little about practice. The word doctrine, as used in the Bible, means teaching of duty, not theory. I preached a sermon about this. We are far too anxious to be definite and to have finished, well-polished, sharp-edged systems — forgetting that the more perfect a theory about the infinite, the surer it is to be wrong, the more impossible it is to be right.
George MacDonald, in a letter to his father, quoted in George MacDonald and His Wife (1924) by Greville MacDonald