In an earlier post in this blog I spoke about the myth of the Enlightenment, which gave rise to the theory of indefinite progress and the forecast of enormous advances for humankind that would be within our reach in the not too distant future. Although the first half of the eighteenth century was a brake on almost all the cultural activities of our civilization, including science, they were delighted with themselves. Friedrich Melchior, Baron von Grimm (1723-1807), expressed it with unequaled candor, in these words :
The eighteenth century has surpassed all the others in the praises it has lavished on itself.
One of the ideas in vogue by that time was the assumption that scientific advances would let man reach immortality, not too far in time. Although the idea, as a distant possibility, goes back to Roger Bacon, it seemed much closer in the late eighteenth century. Hence the anecdote told of the octogenarian wife of marshal Villeroi, who exclaimed, while looking at Professor Charles’s ascent in a hydrogen balloon:
Yes, it is true! They’ll discover the secret of not dying, after I’ll be dead!
The optimistic ideas of the eighteenth century suffered a sudden, impressive turn in the nineteenth, when came to dominate a pessimistic vision of the future of mankind, based mainly on two scientific discoveries:
- The thermal death of the universe, divulged in 1852 by William Thomson (Lord Kelvin), which evolved from the idea of entropy, discovered by Carnot and Clausius: a thermodynamic magnitude that measures the degree of energy disorder, which can only grow in a closed system (isolated from its outside). As the universe is an isolated system, according to the second principle of thermodynamics, its thermal death in a total disorder must be expected in the very long term.
- The discovery of red giant stars as a phase of star evolution, made in 1868 by the Jesuit and Italian astronomer Angelo Secchi, who predicted that the sun will abandon its current phase in a much shorter time than would be necessary to arrive to the thermal death of the universe; a time estimated today in a few billion years.
The end of the universe and the end of the solar system put limits on the hunger for immortality, to the point that for some time not much was said about the subject, although the philosopher Nietzsche, with his idea of the superman, again proposed a more optimistic view which did not last long, for the twentieth century gave a strong push to pessimism. And this time the end of humanity seemed much closer, almost imminent, also due to two discoveries in the field of mass destruction weapons that made possible for man to exterminate himself, not in the very distant future, millions of years away, but in the present:
- Poisonous gases, which I discussed in another post and started from the research of the German chemist Fritz Haber. Their first and most deadly example was mustard gas, used in the First World War with such horrible effects, that nobody (not even Hitler) dared to use it in the second.
- Nuclear weapons, whose arsenals are, and have been for decades, capable of putting an end to human life on Earth.
During the second half of the twentieth century, the world was permanently on the verge of a total nuclear war that would have destroyed our civilization and probably our species. Nuclear warfare and its consequences became one of the favorite subjects of dystopian science-fiction. One of the best was A Canticle for Leibowitz, by Walter M. Miller Jr. (1959).
It is curious that nuclear deterrence would have prevented the unleashing of World War III, as pointed out in a recent article by Carl Bildt, who fears that the total elimination of nuclear weapons could precisely push us towards that scenario.
With the collapse of the Soviet Union, the imminent danger of nuclear war seemed to be receding, resulting in a revival of optimistic ideas during the late twentieth and early twenty-first century and the resurgence of human immortality as something imminent, especially by the philosophical current called transhumanism, a name invented in 1957 by Julian Huxley, who misunderstood the work of Pierre Teilhard de Chardin, as he proved in the prologue he wrote for the English version of The Phenomenon of Man.
Now, however, we begin to realize that increasing nuclear proliferation greatly increases the danger, as expressed significantly in A canticle for Leibowitz:
We've pieced enough together since that was written to know that even some of the lesser rulers of that time had got their hands on such weapons before the holocaust came.
In this novel, when humanity begins to recover from the atomic war a few centuries later, no one remembers which country was the first to trigger the war. The recent evolution of international policy is a good indication of this danger. Are we approaching a new era of pessimism?
 Quoted in , by Rémy Brague.
 Former prime minister of Sweden.
The same post in Spanish