If you see that some aspect of your society is bad, and you want to improve it, there is only one way to do so: you have to improve people. And in order to improve people, you begin with only one thing: you can become better yourself.
The difference between real material poison and intellectual poison is that most material poison is disgusting to the taste, but intellectual poison, which takes the form of cheap newspapers or bad books, can unfortunately sometimes be attractive.
When do lads begin to smoke? Usually when they lose their childish innocence. How is it that smokers can abandon smoking when they come among more moral conditions of life and again start smoking as soon as they fall among a depraved set? Why do gamblers almost all smoke? Why among women do those who lead a regular life smoke least? Why do prostitutes and madmen all smoke? Habit is habit, but evidently smoking stands in some definite connection with the craving to stifle conscience, and achieves the end required of it.
Art is not, as the metaphysicians say, the manifestation of some mysterious idea of beauty or God; it is not, as the aesthetical physiologists say, a game in which man lets off his excess of stored-up energy; it is not the expression of man’s emotions by external signs; it is not the production of pleasing objects; and, above all, it 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 toward well-being of individuals and of humanity.
Leo Tolstoy on art, along with other great definitions from antiquity to today