There is no good reason why the essay should not replace the book, and a lot of good reasons why it should. I am tempted to say — in order to be maximally provocative — that anyone who publishes a book within six years of earning a Ph.D. should be denied tenure. The chances a person at that stage can have published something worth chopping that many trees down is unlikely. I ask you: How are you preparing for the future that could be yours and mine? We — I mean the world in general — don’t need a lot of bad writing. We need some great writing.

From the archive:

Dyson: I'm accustomed to living among very long-lived institutions in England, and I'm always surprised that the rest of the world is so different. At the beginning of Imagined Worlds, I mentioned the avenue of trees at Trinity College, Cambridge. ... Trinity is an astonishing place because it has been a fantastic producer of great science for 400 years and continues to be so.

They planted an avenue of trees in the early 18th century, leading up from the river to the college. This avenue of trees grew very big and majestic in the course of 200 years. When I was a student there 50 years ago, the trees were growing a little dilapidated, though still very beautiful. The college decided that for the sake of the future, they would chop them down and plant new ones. Now, 50 years later, the new trees are half grown and already looking almost as beautiful as the old ones.

That's the kind of thinking that comes naturally in such a place, where 100 years is nothing.

Q: President Bush has talked about our staying in Iraq for fifty years.

McCain: Make it a hundred.