Isaiah Berlin, a ciência e os perigos da certeza

terça-feira, outubro 28, 2014

Isaiah Berlin, science and the dangers of certainty 

By Wavefunction on Monday, October 27, 2014

The essence of science is uncertainty. The scientific process gropes, not finds, its way to the truth. And yet there are those who have sought certainty and sacred truth not just in science but in human affairs. In science this illusory search can be a mere annoyance or at worse it can be a recipe for shattered careers and wasted man hours, but in human affairs it can lead to the most horrific tragedies. As Jacob Bronowski poignantly put it in "The Ascent of Man""Science is a very human form of knowledge. We are always at the brink of the known; we always feel forward for what is to be hoped. Every judgment in science stands on the edge of error and is personal. Science is a tribute to what we can know although we are fallible. In the end, the words were said by Oliver Cromwell: "I beseech you in the bowels of Christ: Think it possible you may be mistaken."

The great philosopher of ideas Isaiah Berlin delivers that last message to us from the grave with resounding sincerity in an article published by the New York Review of Books which reprints Berlin's 1996 address as commencement speaker at the University of Toronto. Berlin lived from 1909 to 1997 and he is most widely known to the public as the originator of the distinction between hedgehogs and foxesBut he was also recognized as one of the most thoughtful thinkers and writers of his generation, and because of his long life and wide-ranging intellect was in a good position to catalogue the horrors of the entire century and distill their central message.

That central lesson, as Berlin puts it, is the gospel of the one unalterable truth the meld of sacred values that one must pursue at the expense of everything else. That gospel is hardly new - men have pursued it to nefarious and tragic ends for centuries - but it saw its most horrific culmination in terms of scale and purposeful slaughter in the crimes of the twentieth century.

Berlin lays most of the blame for the century's excesses at the feet of Karl Marx, and it is hard to argue that if there was one philosopher who has caused so many ills during the last two hundred years it has been Marx. But there were certainly others, dogmatic and prejudiced men whose sometimes idle speculations fueled other murderous philosophies. There were the armchair philosophers and casual anti-Semities (de GobineauChamberlainfor instance whose writings inspired Hitler during his early years. These armchair philosophers - and Berlin's words about the momentous consequences that the 'mere' words and ideas of philosophers can have are timeless - knew they were in possession of the one truth just like their predecessors. And this led to ruin for millions. Not all these philosophers actively plotted the murder of their fellow countrymen of course, but they were clearly unaware how their vision of some Universal Truth could lead others to do so. Here's the problem:

If you are truly convinced that there is some solution to all human problems, that one can conceive an ideal society which men can reach if only they do what is necessary to attain it, then you and your followers must believe that no price can be too high to pay in order to open the gates of such a paradise. Only the stupid and malevolent will resist once certain simple truths are put to them. Those who resist must be persuaded; if they cannot be persuaded, laws must be passed to restrain them; if that does not work, then coercion, if need be violence, will inevitably have to be used—if necessary, terror, slaughter. Lenin believed this after reading Das Kapital, and consistently taught that if a just, peaceful, happy, free, virtuous society could be created by the means he advocated, then the end justified any methods that needed to be used, literally any.

The embrace of any kind of means as justification for ends is hardly Lenin's invention, and we can be sure that men will continue to wield this fatal idea. But there is an even more fundamental reason why such ideas are dangerous. It's not just the lives they take, but the inherent flaws they present. Here Berlin reminds us of the essential role that pluralism has played in human history, a philosophy that he himself did so much to expound on.

This is the idea of which I spoke, and what I wish to tell you is that it is false. Not only because the solutions given by different schools of social thought differ, and none can be demonstrated by rational methods—but for an even deeper reason. The central values by which most men have lived, in a great many lands at a great many times—these values, almost if not entirely universal, are not always harmonious with each other. Some are, some are not. Men have always craved for liberty, security, equality, happiness, justice, knowledge, and so on. But complete liberty is not compatible with complete equality—if men were wholly free, the wolves would be free to eat the sheep. Perfect equality means that human liberties must be restrained so that the ablest and the most gifted are not permitted to advance beyond those who would inevitably lose if there were competition. Security, and indeed freedoms, cannot be preserved if freedom to subvert them is permitted. Indeed, not everyone seeks security or peace, otherwise some would not have sought glory in battle or in dangerous sports.

Justice has always been a human ideal, but it is not fully compatible with mercy. Creative imagination and spontaneity, splendid in themselves, cannot be fully reconciled with the need for planning, organization, careful and responsible calculation. Knowledge, the pursuit of truth—the noblest of aims—cannot be fully reconciled with the happiness or the freedom that men desire, for even if I know that I have some incurable disease this will not make me happier or freer. I must always choose: between peace and excitement, or knowledge and blissful ignorance. And so on.

It is the inability to grasp this fundamental tussle between different values that in part leads people to believe in holy truths. But Berlin is honest and reflective enough to admit that he sees no straightforward solution to this dilemma. This is perhaps because the only solution is to admit the dilemma and live with it, to respect a plurality of opinion and abide by the views of multitudes, to recognize that the contradictions that man presents are the contradictions that man contains. In fact this reconciliation with differing views lies at the heart of both liberal democracy and scientific exploration.

Science has always prided itself on respecting a plurality of views, perhaps because its practitioners have realized how fickle pronouncements of ultimate truth are. At the end of the nineteenth century a few leading physicists declared that fundamental physics was now set in stone and all that was needed was the drive toward more accurate measurements. The world of relativity and quantum theory shattered that fond illusion. Similarly many experts in evolution believed that the genome was unalterable once it was passed on from parents to children. The discovery of epigenetics put a completely different spin on genetic inheritance. The same slaying of longstanding beliefs - Aristotle's four elements, vitalism, the ether - has pervaded the history of science.

It is thus clear that science has always suffered when its adherents have insisted that there was one truth to be known, shared and cherished. But it - and humanity - have suffered even more when the belief in such a truth came not from the scientific edifice itself from but from a political or social outlook that used that edifice to its own ends. The greatest harm comes not when scientists claim universal truth but when all of us, scientists as well as non-scientists, believe that science should support what we believe are sacred political or social values.