A cultivated man of taste and feeling can find much that is beautiful in nature and art; and if he is also a moral idealist, he will find much that is good and virtuous in human life and experience. But it would be incomplete to stop there and ignore the fact that there is also around us much that is base, dark, and even evil. The two sides put together form a complete observation. But it is only the mystics and the philosophers who can see--because it requires a deeper penetration than the intellect and the senses can give--that the dark side deals with the world of appearances, a world which is fleeting and ephemeral, whereas the good side and the beautiful side is merely a hint of that other world closer to Reality.
-- Notebooks Category 11: The Negatives > Chapter 1: Their Nature > # 20