Because heat drove the mine machinery, propelled the locomotives, animated the propeller-driven or paddlewheel boats — those very things that gave England the temporary mastery of the seas — because, via the burning of coal, it stoked steel foundries (from which the forge masters drew their financial might), heat destroyed the agrarian, cool society of water mills and windmills.

    It created a new and burning society. Everywhere, fires unknown before that time were lit in such a way that a thousand things that had been stable for a long time disappeared, while others began to move. Then cities were smothered under blankets of unbreathable smoke, and London's streets, squares, and rooftops vanished under the fog from those fires. In our youth, we could still visit this soft and opaque capital, the same one that Turner painted through veils of fog.

    We will not be surprised, then, to contemplate dangerous fires in Turner, like The Burning of the Houses of Parliament (1835), or the mobile smoke of steamboats spitting sooty clouds from their smokestacks, like those of the tugboat towing The Fighting 'Temeraire' (1838) toward its last berth. He makes us see what he observed: the England and Scotland of his time. But he rarely paints the landscapes of traditional England, like Gainsborough or Constable — its fields, meadows, and gardens still plunged in the old society of the 18th century and its agrarian, aristocratic world. Rather, he makes us see the novelties of a country in the throes of a complete scientific, technological, and social renewal. To clarify both the industrial revolution as event and the canvasses of Turner that reflect it, nature and geography thus give way in favor of the history of mechanical and social sciences: economics and sociology.

    On the strength of such interpretations, I wrote in my youth a short tract about these splendors. I thought there was sense and truth in it, since Turner's canvasses spit flame like those new steamboats, and were thus quite the opposite of, for example, an earlier work by George Garrard, whose drawing follows the mechanical latticework suspended from the tackle of a docked wooden ship, next to The Warehouse of Samuel Whitbread the brewer, a hangar where all the old tools are kept . . .

    If Garrard illustrates, in a certain sense, the Analytical Mechanics of Lagrange, his contemporary Turner, for his part, stages Carnot's theory of heat engines, written at the same time. The two works translate the two dynamics, the old one of cold power, and the new thermodynamics, whose name would be born later and which replaced the old thermology of hearths and fireplaces, of household combustion. The change of draughtsmanship and of color palette points to the evolution between two systems of tools, two sets of machines, two conceptions of work. Two worlds, in sum, conceived by — if not born of — these two sciences.

    It was stunning to me, this exact commonality of views between scientists and artists. It was as if the latter had conceived the same ideas as the former, in the same universe and in the same time — without, of course, their knowing or being able to influence one another. Convinced by the dazzling and rigorous detail of a parallel that opened another dimension of analysis, I never reconsidered these results. Until very recently.

    A New Library Inside a Refrigerator

    But now, here is something new, come not from heat, but from cold. Results obtained via core samples drilled through layers of ice in the glaciers of Greenland have laid waste to my old intuition, which had sprung from the history of natural and social sciences.

    Fallen every year in these zones close to the North Pole, snow forms strata that eventually harden into layers of ice covered by the snowfall of each succeeding year. Little by little an ensemble of horizontal pages forms, which is then vertically cut by the drilled core samples. The elements suspended in the air are captured by the snow, season after season, and are set down with the snow and stay there, preserved by pressure and cold. Chemical analysis of these elements, prisoners from that moment on in each of these successive strata, restores the state of the atmosphere in the very year of each snowfall; it makes legible, as in an open book, flipped page by page, the diverse climatic moments of eras whose dates and memory we had often lost.

    In the years when Turner was painting his sooty and pyrotechnical canvasses, Tambora, a volcano over nine thousand feet high, and situated in the Lesser Sunda Islands of Indonesia, exploding suddenly, spewed clouds of burning ash into the upper atmosphere. Terrestrial attraction long held them above the equatorial belt like a satellite. Later, they dispersed toward the temperate zones and finally over the poles, where they fell with the snow, settled there, and were preserved. The core samples in which they are found today attest that the island, and then the whole globe, endured on that day of wrath and in the months that followed one of the most frightening eruptions in the recent history of the planet. Thanks to Tambora, in those years England — among other neighboring countries — under a cloud of volcanic ash spewed up from Indonesia, was regaled with lacquered shadows at noon, with winy dawns and carnelian dusks.

    To be sure, Turner painted steamships and fires of all sorts, but the sieve of ashen fog that dropped like a veil between things as they usually are and his strange canvasses Ñ did this ashy screen come from the eruption of that volcano in the Sunda Islands, or from the social reflections of the industrial revolution? Did it come from the phenomena of nature or from the effects of society? Were the air, the light, and the sky of London direct manifestations of telluric powers, or were they indirect manifestations of relations of force remodeled by fire- driven machines and the factory proletariat? Since the immediate moves more quickly than the mediated, geophysics seems more powerful than economic history, Tambora more powerful than Marxist analysis. Was I mistaken? I am ready to admit it.

    By shouting that the fine arts, like mental illness or scientific discoveries, are socially determined, do we keep ourselves from hearing even the volcanoes' thunder? By contrast, how many epistemologies have not heard the noise of Nagasaki? In physics, an experiment has no social effects. Scientific ideas must deafen us so that we hear neither eruptions nor atomic bombs! In the first of these two cases, social science forgets climate — the atmosphere itself and its opacities, the earth and its instabilities. In the second, indifferent to humanity, the hard sciences seem to ignore war, its murders and its miseries, and death, received or given. Does the ear's hearing or the eye's vision improve according to the deafening or blinding of the other?

    Yet groups of mortals do live in the world: this obvious fact, accessible to laypeople, is invisible to the division of the sciences. Where, then, does this reciprocal blindness and deafness come from, the absence of contact between kinds of knowledge so divided that their exclusive limits produce, more than error, the lacunary ignorance of an empty set?

    Will it suffice if the twins stop arguing so that they can hear what people outside the family are saying? Will we ever deceive ourselves by anything but corporatism? Because we're so fond of explaining the universe and history according to the groups that we belong to, does our specialization forever block up our eyes and our ears?

    Yes, intelligence, discovery and invention — in short, the truth — are born from filling out the sets emptied by reciprocal deafness or blindness. Filled back up, these intersections have as much to do with nature and society as they do with science and the humanities.

    If the humanities mean something, then they must define humanity, and in fact they never stop talking about identity, in culture, in gender, in language. How, then, to define this identity in its turn? Tautologically, identity means that an individual is no one other than him or herself. To verify a person's identity, customs examines his or her passport, whose first page announces a first name, last name, height, eye color, nationality ... information that expresses associations of belonging: to the set of people with the same name, the same body type, the same language, etc. ... I am such and such an individual and I belong, among other things, to one subset, 'male,' and to another, 'French-speaking,' etc. ... Logic and mathematics designate belonging and identity under two different signs, and confusing them leads to grave errors.

    What is racism, then? The reduction of an individual's identity to one of the categories that he or she belongs to. So it is said of someone: he's African, she's a woman, he's Chicano, etc. Reducing identity to a simple act of belonging, the unfortunately all too common expressions 'cultural identity,' 'masculine identity,' or 'feminine identity' express racism in its pure form. You are yourself; thou art thou; we cannot be reduced to a gender, nor to a sex, nor to a language, nor to a culture. The confusion between belonging and identity leads to more than logical and formal errors: it leads to moral wrongs and to the crimes of racism.

    So the person lives in the place where many subsets overlap: identity is born from the intersection of belongings. The richness of the first depends, we know well, on the number of the second.

    Similarly, a man of culture, informed about his own culture and happy to belong to it, has no right to this title unless he knows and appreciates many cultures — unless he cultivates their intersection. The depth of the first depends, we know well, on the number of the second. Likewise, a scientist or scholar has no right to that title unless, ceasing to defend his own disciples or her own discipline, she stops explaining everything from her discipline's point of view, but admires other disciplines, far or near, and learns from them.

    Identity comes from the intersection of belongings; culture comes from the intersection of cultures; discovery or true invention spring from the intersection of disciplines. As a result the hard sciences and the humanities find themselves on the same footing as far as truth is concerned. What one can say about humanist culture can also be said about scientific truth: multiculturalism, in the first case, equals, in the second, interdisciplinarity.

    To try to speak the truth about Turner's canvasses, I should therefore travel the world, from the Sunda Islands to Greenland, before returning to the London fog. I should also move from geology to glaciology, before returning to sociology, economics, the history of science and the history of art. I must cross borders and seas, on Earth as much as in the country of Encyclopedia.

    The question of truth, and therefore of discovery, is thus posed in the same way as the question of culture or cultures. Just as there are French, Italian, and Mexican cultures, so official knowledge is divided into provinces: logic, astronomy, sociology..., and scholarly or scientific truth haunt the intersections between disciplines. Just as the passion for belonging often engenders violence, and in fact human misery in general, so belonging to a single branch of knowledge engenders corporatism. Like the world and like knowledge, the university is also divided into provinces linked in a relation of domination, some having more power than others. And here, perhaps, we touch on the gravest danger for today's universities: the danger of losing, through provincialism, the truth of their name, and the fertility that this universality promises. Can discovery come about in a closed group, ranged in battle order, in which all defend only their own interests? Why does it always come from elsewhere, and not from the corporate body? Because the corporation does not concern itself with truth, but with money, with power, and with glory.

    Michel Serres is a philosopher of science, a faculty member of Stanford University, and a member of the French Academy. The following is an excerpt from the Hayward- Keniston lecture delivered at the University on October 31, 1996. The full text of the lecture will be published in SubStance in a special issue devoted to Michel Serres. The issue can be obtained from: Journals Dept., University of Wisconsin Press, 114 N. Murray St., Madison, WI 53715. The excerpt is printed with the permission of Substance The lecture is translated by Catherine Brown with William Paulson.