At the same time, science requires the most vigorous and uncompromising scepticism, because the vast majority of ideas are simply wrong, and the only way to winnow the wheat from the chaff is by critical experiment and analysis. If you’re open to the point of gullibility and have not a microgram of sceptical sense in you, then you cannot distinguish the promising ideas from the worthless ones. Uncritically accepting every proffered notion, idea and hypothesis is tantamount to knowing nothing. Ideas contradict one another; only through sceptical scrutiny can we decide among them. Some ideas really are better than others.
The judicious mix of these two modes of thought is central to the success of science. Good scientists do both. On their own, talking to themselves, they churn up many new ideas, and criticize them systematically. Most of the ideas never make it to the outside world. Only those that pass a rigorous self-filtration make it out to be criticized by the rest of the scientific community.
Because of this dogged mutual and self-criticism, and the proper reliance on experiment as the arbiter between contending hypotheses, many scientists tend to be diffident about describing their own sense of wonder at the dawning of a wild surmise. This is a pity, because these rare exultant moments demystify and humanize the scientific endeavour.
No one can be entirely open or completely sceptical. We all must draw the line somewhere.* An ancient Chinese proverb advises, ‘Better to be too credulous than too sceptical’, but this is from an extremely conservative society in which stability was much more prized than freedom and where the rulers had a powerful vested interest in not being challenged. Most scientists, I believe, would say, ‘Better to be too sceptical than too credulous’. But neither is easy. Responsible, thoroughgoing, rigorous scepticism requires a hardnosed habit of thought that takes practice and training to master. Credulity — I think a better word here is ‘openness’ or ‘wonder’ – does not come easily either. If we really are to be open to counterintuitive ideas in physics or social organization or anything else, we must grasp those ideas. It means nothing to be open to a proposition we don’t understand.
[* And in some cases scepticism would be simply silly, as for example in learning to spell.]
Both scepticism and wonder are skills that need honing and practice. Their harmonious marriage within the mind of every schoolchild ought to be a principal goal of public education. I’d love to see such a domestic felicity portrayed in the media, television especially: a community of people really working the mix – full of wonder, generously open to every notion, dismissing nothing except for good reason, but at the same time, and as second nature, demanding stringent standards of evidence; and these standards applied with at least as much rigour to what they hold dear as to what they are tempted to reject with impunity.
18
The Wind Makes Dust
[T]he wind makes dust because it intends to blow, taking away our footprints.
Specimens of Bushmen Folklore,
W.H.I. Bleek and L.C. Lloyd,
collectors, L.C. Lloyd, editor (1911)
[E]very time a savage tracks his game he employs a minuteness of observation, and an accuracy of inductive and deductive reasoning which, applied to other matters, would assure some reputation as a man of science . . . [T]he intellectual labour of a ‘good hunter or warrior’ considerably exceeds that of an ordinary Englishman.
Thomas H. Huxley, Collected Essays,
Volume II, Darwiniana: Essays
(London: Macmillan, 1907), pp. 175-6
[from ‘Mr Darwin’s Critics’ (1871)]
Why should so many people find science hard to learn and hard to teach? I’ve tried to suggest some of the reasons – its precision, its counterintuitive and disquieting aspects, its prospects of misuse, its independence of authority, and so on. But is there something deeper? Alan Cromer is a physics professor at Northeastern University in Boston who was surprised to find so many students unable to grasp the most elementary concepts in his physics class. In Uncommon Sense: The Heretical Nature of Science (1993), Cromer proposes that science is difficult because it’s new. We, a species that’s a few hundred thousand years old, discovered the method of science only a few centuries ago, he says. Like writing, which is only a few millennia old, we haven’t gotten the hang of it yet – or at least not without very serious and attentive study.
Except for an unlikely concatenation of historical events, he suggests, we would never have invented science:
This hostility to science, in the face of its obvious triumphs and benefits, is … evidence that it is something outside the mainstream of human development, perhaps a fluke.
Chinese civilization invented movable type, gunpowder, the rocket, the magnetic compass, the seismograph, and systematic observations and chronicles of the heavens. Indian mathematicians invented the zero, the key to comfortable arithmetic and therefore to quantitative science. Aztec civilization developed a far better calendar than that of the European civilization that inundated and destroyed it; they were better able, and for longer periods into the future, to predict where the planets would be. But none of these civilizations, Cromer argues, had developed the sceptical, inquiring, experimental method of science. All of that came out of ancient Greece:
The development of objective thinking by the Greeks appears to have required a number of specific cultural factors. First was the assembly, where men first learned to persuade one another by means of rational debate. Second was a maritime economy that prevented isolation and parochialism. Third was the existence of a widespread Greek-speaking world around which travelers and scholars could wander. Fourth was the existence of an independent merchant class that could hire its own teachers. Fifth was the Iliad and the Odyssey, literary masterpieces that are themselves the epitome of liberal rational thinking. Sixth was a literary religion not dominated by priests. And seventh was the persistence of these factors for 1,000 years.
That all these factors came together in one great civilization is quite fortuitous; it didn’t happen twice.
I’m sympathetic to part of this thesis. The ancient lonians were the first we know of to argue systematically that laws and forces of Nature, rather than gods, are responsible for the order and even the existence of the world. As Lucretius summarized their views, ‘Nature free at once and rid of her haughty lords is seen to do all things spontaneously of herself without the meddling of the gods.’ Except for the first week of introductory philosophy courses, though, the names and notions of the early lonians are almost never mentioned in our society. Those who dismiss the gods tend to be forgotten. We are not anxious to preserve the memory of such sceptics, much less their ideas. Heroes who try to explain the world in terms of matter and energy may have arisen many times in many cultures, only to be obliterated by the priests and philosophers in charge of the conventional wisdom, as the Ionian approach was almost wholly lost after the time of Plato and Aristotle. With many cultures and many experiments of this sort, it may be that only on rare occasions does the idea take root.
Plants and animals were domesticated and civilization began only ten or twelve thousand years ago. The Ionian experiment is 2,500 years old. It was almost entirely expunged. We can see steps towards science in ancient China, India and elsewhere, even though faltering, incomplete, and bearing less fruit. But suppose the lonians had never existed, and Greek science and mathematics never flourished. Is it possible that never again in the history of the human species would science have emerged? Or, given many cultures and many alternative historical skeins, isn’t it likely that the right combination of factors would come into play somewhere else, sooner or later – in the islands of Indonesia, say, or in the Caribbean on the outskirts of a Mesoamerican civilization untouched by Conquistadores, or in Norse colonies on the shores of the Black Sea?
The impediment to scientific thinking is not, I think, the difficulty of the subject. Complex intellectual feats have been mainstays even of oppressed cultures. Shamans, magicians and theologians are highly skilled in their intricate and arcane arts. No, the impediment is political and hierarchical. In those cultures lacking unfamiliar challenges, external or internal, where fundamental change is unneeded, novel ideas need not be encouraged. Indeed, heresies can be declared dangerous; thinking can be rigidified; and sanctions against impermissible ideas can be enforced – all without much harm. But under varied and changing environmental or biological or political circumstances, simply copying the old ways no longer works. Then, a premium awaits those who, instead of blandly following tradition, or trying to foist their preferences on to the physical or social Universe, are open to what the Universe teaches. Each society must decide where in the continuum between openness and rigidity safety lies.
Greek mathematics was a brilliant step forward. Greek science, on the other hand – its first steps rudimentary and often uninformed by experiment – was riddled with error. Despite the fact that we cannot see in pitch darkness, they believed that vision depends on a kind of radar that emanates from the eye, bounces off what we’re seeing, and returns to the eye. (Nevertheless, they made substantial progress in optics.) Despite the obvious resemblance of children to their mothers, they believed that heredity was carried by semen alone, the woman a mere passive receptacle. They believed that the horizontal motion of a thrown rock somehow lifts it up, so that it takes longer to reach the ground than a rock dropped from the same height at the same moment. Enamoured of simple geometry, they believed the circle to be ‘perfect’; despite the ‘Man in the Moon’ and sunspots (occasionally visible to the naked eye at sunset), they held the heavens also to be ‘perfect’; therefore, planetary orbits had to be circular.