Freeman J. Dyson
Institute for Advanced Study
Princeton, New Jersey
 

I.  Bernal's Book  

The World, The Flesh and the Devil; An Enquiry into the Future of the Three Enemies of the Rational Soul, is the full title of Bernal's first book which he wrote at the age of 28.  Forty years later he said in a foreword to the second edition, “This short book was the first I ever wrote.  I have a great attachment to it because it contains many of the seeds of ideas which I have been elaborating throughout my scientific life.  It still seems to me to have validity in its own right.”  It must have been a consolation to Bernal, crippled and incapacitated in the last years of his life, to know that this work of his spring-time was again being bought and read by a new generation of young readers.

Bernal's book begins with these words:  “There are two futures, the future of desire and the future of fate, and man's reason has never learnt to separate them.”  I do not know of any finer opening sentence of a work of literature in English.  Bernal's modest claim that his book “still seems to have validity in its own right” holds good in 1972 as it did in 1968.  Enormous changes have occurred since he wrote the book in 1929, both in science and in human affairs.  It would be miraculous if nothing in it had become dated or superseded by the events of the last forty years.  But astonishingly little of it has proved to be wrong or irrelevant to our present concerns.

I decided that the best way I can do honor to Bernal in this lecture is to use his book as a point of departure for my own speculations about the future of mankind.  I shall not expound or criticize the book in detail.  I hope that much of what I shall say will be fresh and will go in some directions beyond Bernal's horizons.  But it will be obvious to those of my audience who have read Bernal that my ideas are deeply influenced by him.  To those of you who have not read Bernal I hope that I may provide a stimulus to do so.

Bernal saw the future as a struggle of the rational side of man's nature against three enemies.  The first enemy he called the World, meaning scarcity of material goods, inadequate land, harsh climate, desert, swamp, and other physical obstacles which condemn the majority of mankind to lives of poverty.  The second enemy he called the Flesh, meaning the defects in man's physiology that expose him to disease, cloud the clarity of his mind, and finally destroy him by senile deterioration.  The third enemy he called the Devil, meaning the irrational forces in man's psychological nature that distort his perceptions and lead him astray with crazy hopes and fears, overriding the feeble voice of reason.  Bernal had faith that the rational soul of man would ultimately prevail over these enemies.  But he did not foresee cheap or easy victories.  In each of these struggles, he saw hope of defeating the enemy only if mankind is prepared to adopt extremely radical measures.

Briefly summarized, the radical measures which Bernal prescribed were the following.  To defeat the World, the greater part of the human species will leave this planet and go to live in innumerable freely floating colonies scattered through outer space.  To defeat the Flesh, humans will learn to replace failing organs with artificial substitutes until we become an intimate symbiosis of brain and machine.  To defeat the Devil, we shall first reorganize society along scientific lines, and later learn to exercise conscious intellectual control over our moods and emotional drives, intervening directly in the affective functions of our brains with technical means yet to be discovered.  This summary is a crude oversimplification of Bernal's discussion.  He did not imagine that these remedies would provide a final solution to the problems of humanity.  He well knew that every change in the human situation will create new problems and new enemies of the rational soul.  He stopped where he stopped because he could not see any farther.  His chapter on “The Flesh” ends with the words:  “That may be an end or a beginning, but from here it is out of sight.”

How much that was out of sight to Bernal in 1929 can we see from the vantage point of 1972?  The first and most obvious difference between 1929 and 1972 is that we have now a highly vocal and well-organized opposition to the further growth of the part that technology plays in human affairs.  The social prophets of today look upon technology as a destructive rather than a liberating force.  In 1972 it is highly unfashionable to believe as Bernal did that the colonization of space, the perfection of artificial organs and the mastery of brain physiology are the keys to man's future.  Young people in tune with the mood of the times regard space as irrelevant, and they consider ecology to be the only branch of science that is ethically respectable.  However, it would be wrong to imagine that Bernal's ideas were more in line with popular views in 1929 than they are in 1972.  Bernal was never a man to swim with the tide.  Technology was unpopular in 1929 because it was associated in people's minds with the gas warfare of the first World War, just as now it is unpopular by association with Hiroshima and the defoliation of Vietnam.  In 1929 the dislike of technology was less noisy than today but no less real.  Bernal understood that his proposals for the remaking of man and society flew in the teeth of deeply entrenched human instincts.  He did not on that account weaken or compromise his statement.  He believed that a rational soul would ultimately come to accept his vision of the future as reasonable, and that for him was enough.  He foresaw that mankind might split into two species, one following the technological path which he described, the other holding on as best it could to the ancient folkways of natural living.  And he recognized that the dispersion of mankind into the vastness of space is precisely what is required for such a split of the species to occur without intolerable strife and social disruption.  The wider perspective which we have gained between 1929 and 1972 concerning the harmful effects of technology affects only the details and not the core of Bernal's argument.

Another conspicuous difference between 1929 and 1972 is that men have now visited the moon.  Surprisingly, this fact makes little difference to the plausibility of Bernal's vision of the future.  Bernal in 1929 foresaw cheap and massive emigration of human beings from the earth.  He did not know in detail how it should be done.  We still do not know how it should be done.  Certainly it will not be done by using the techniques that took men to the moon in 1969.  We know that in principle the cost in energy or fuel of transporting people from Earth into space need be no greater than the cost of transporting them from New York to London.  To translate this “in principle” into reality will require two things: first a great advance in the engineering of hypersonic aircraft, and second the growth of a traffic massive enough to permit large economies of scale.  It is likely that the Apollo vehicle bears the same relation to the cheap mass-transportation space-vehicle of the future as the majestic airship of the 1930s bears to the Boeing 747 of today.  The airship R101 was absurdly large, beautiful, expensive, and fragile, just like the Apollo Saturn 5.  If this analogy is sound, and I believe it is, we shall have transportation into space at a reasonable price within about fifty years from now.  But my grounds for believing this are not essentially firmer than Bernal's were for believing it in 1929.