One cannot long remain so absorbed in contemplation of emptiness without being increasingly attracted to it. In vain one bestows on it the name of infinity; this does not change its nature. When one feels such pleasure in non-existence, one's inclination can be completely satisfied only by completely ceasing to exist.
Sadness does not inhere in things; it does not reach us from the world and through mere contemplation of the world. It is a product of our own thought. We create it out of whole cloth.
Man could not live if he were entirely impervious to sadness. Many sorrows can be endured only by being embraced, and the pleasure taken in them naturally has a somewhat melancholy character. So, melancholy is morbid only when it occupies too much place in life; but it is equally morbid for it to be wholly excluded from life.