Thinking is the activity I love best, and writing to me is simply thinking through my fingers. I can write up to 18 hours a day. Typing 90 words a minute, I've done better than 50 pages a day. Nothing interferes with my concentration. You could put an orgy in my office and I wouldn't look up-well, maybe once.

Modern science fiction is the only form of literature that consistently considers the nature of the changes that face us.

As artists and traders in medieval cities began to form organizations, they instituted tough initiation ceremonies. Journeymen in Bergen, Norway, were shoved down a chimney, thrown three times into the sea, and soundly whipped. Such rites made belonging to the guild or corporation more precious to those who were accepted, and survived.

The significant chemicals of living tissue are rickety and unstable, which is exactly what is needed for life.

But life is glorious when it is happy; days are carefree when they are happy; the interplay of thought and imagination is far and superior to that of muscle and sinew. Let me tell you, if you don't know it from your own experience, that reading a good book, losing yourself in the interest of words and thoughts, is for some people (me, for instance) an incredible intensity of happiness.

Isn't it sad that you can tell people that the ozone layer is being depleted, the forests are being cut down, the deserts are advancing steadily, that the greenhouse effect will raise the sea level 200 feet, that overpopulation is choking us, that pollution is killing us, that nuclear war may destroy us - and they yawn and settle back for a comfortable nap. But tell them that the Martians are landing, and they scream and run.

All evil is good become cancerous.