"Every time I entered into heightened awareness I could not cease marveling at the difference between my two sides. I always felt as if a veil had been lifted from my eyes, as if I had been partially blind before and now I could see. The freedom, the sheer joy that used to possess me on those occasions cannot be compared with anything else I have ever experienced. Yet at the same time, there was a frightening feeling of sadness and longing that went hand in hand with that freedom and joy. Don Juan had told me that there is no completeness without sadness and longing, for without them there is no sobriety, no kindness. Wisdom without kindness, he said, and knowledge without sobriety are useless."
– Carlos Castaneda