Free The Scientist as Rebel by Freeman J. Dyson Page B

teeth; and being sown up and down, may chance to spring up armed men.
    The important word in Milton’s statement is “thereafter.” Books should not be convicted and imprisoned until after they have done some damage. What Milton declared unacceptable was prior censorship, prohibiting books from ever seeing the light of day. Next, Milton comes to the heart of the matter, the difficulty of regulating “things, uncertainly and yet equally working to good and to evil”:
    Suppose we could expel sin by this means; look how much we thus expel of sin, so much we expel of virtue: for the matter of them both is the same; remove that, and ye remove them both alike.
    This justifies the high providence of God, who, though he commands us temperance, justice, continence, yet pours out before us even to a profuseness all desirable things, and gives us minds that can wander beyond all limit and satiety. Why should we then affect a rigor contrary to the manner of God and of nature, by abridging or scanting those means, which books freely permitted are, both to the trial of virtue, and the exercise of truth. It would be better done to learn that the law must needs be frivolous which goes to restrain things, uncertainly and yet equally working to good and to evil.
    My last quotation expresses Milton’s patriotic pride in the intellectual vitality of seventeenth-century England, a pride that twenty-first-century Americans have good reason to share:
    Lords and Commons of England, consider what Nation it is whereof ye are, and whereof ye are the governors: a Nation notslow and dull, but of a quick, ingenious, and piercing spirit, acute to invent, subtle and sinewy to discourse, not beneath the reach of any point the highest that human capacity can soar to.… Nor is it for nothing that the grave and frugal Transylvanian sends out yearly from as far as the mountainous borders of Russia, and beyond the Hercynian wilderness, not their youth, but their staid men, to learn our language and our theologic arts.
    Perhaps, after all, as we struggle to deal with the enduring problems of reconciling individual freedom with public safety, the wisdom of a great poet who died more than three hundred years ago may still be helpful.
    That was the end of the debate. No vote was taken to determine who won. The purpose of the debate was not to win but to educate. Bill Joy and I remain friends.
    1. HarperCollins, 2002.
    2. This description of my debate with Bill Joy is taken from a lecture that I gave at the University of Virginia in 2004. The lecture will be published in a forthcoming book,
A Many-Colored Glass: Reflections on the Place of Life in the Universe
(University of Virginia Press, 2006).

5
WHAT A WORLD!
    IT IS REFRESHING to read a book full of facts about our planet and the life that has transformed it, written by an author who does not allow facts to be obscured or overshadowed by politics. Vaclav Smil is well aware of the political disputes that are now raging about the effects of human activities on climate and biodiversity, but in
The Earth’s Biosphere: Evolution, Dynamics, and Change
1 he does not give them more attention than they deserve. He emphasizes the enormous gaps in our knowledge, the sparseness of our observations, and the superficiality of our theories. He calls attention to the many aspects of planetary evolution that are poorly understood, and that must be better understood before we can reach an accurate diagnosis of the present condition of our planet. When we are trying to take care of a planet, just as when we are taking care of a human patient, diseases must be diagnosed before they can be cured.
    The book has two themes, a major and a minor one. The major theme is the description of the biosphere. The biosphere is the interacting web of plants and rocks, fungi and soils, animals and oceans, microbes and air that constitutes the habitat of life on our planet. To understand the biosphere, it is essential to see it from both