"My friend Stewart Brand, who is now 69, has been arranging his life in blocks of 5 years. Five years is what he says any project worth doing will take. From moment of inception to the last good-riddance, a book, a campaign, a new job, a start-up will take 5 years to play through. So, he asks himself, how many 5 years do I have left? He can count them on one hand even if he is lucky. So this clarifies his choices. If he has less than 5 big things he can do, what will they be?"