To evoke in oneself a feeling one has once experienced, and having evoked it in oneself then, by means of movements, lines, colours, sounds, or forms expressed in words, so to transmit that feeling that others may experience the same feeling—this is the activity of art. (Chapter 5)
Art is a human activity, consisting in this, that one man consciously, by means of certain external signs, hands on to others feelings he has lived through, and that other people are infected by these feelings, and also experience them. (Chapter 5)
...(art) is not pleasure; but it is a means of union among men, joining them together in the same feelings, and indispensable for the life and progress towards well-being of individuals and of humanity. (Chapter 5)
Formerly, people feared lest among the works of art there might chance to be some causing corruption, and they prohibited art altogether. Now, they only fear lest they should be deprived of any enjoyment art can afford, and patronise any art. And I think the last error is much grosser than the first, and that its consequences are far more harmful. (Chapter 5)
So that the majority of the highest classes of that age, even the popes and the ecclesiastics, really believed in nothing at all. In the Church doctrine these people did not believe, for they saw its insolvency; but neither could they follow Francis of Assisi, Keltchitsky, and most of the heretics, in acknowledging the moral, social teaching of Christ, for that teaching undermined their social position. And so these people remained without any religious view of life. And, having none, they could have no standard wherewith to estimate what was good and what was bad art but that of personal enjoyment. And, having acknowledged their criterion of what was good to be pleasure, i.e., beauty, these people of the upper classes of European society went back in their comprehension of art to the gross conception of the primitive Greeks which Plato had already condemned. And conformably to this understanding of life a theory of art was formulated. (Chapter 6)