The encounter of environmental history and intellectual history is a union of two insidiously oceanic inquiries. “Oceanic” in the sense of limitlessness, or oneness with the universe.Footnote ¹ “All history is the history of thought”, and the history of thought is in modern intellectual history a universal investigation, of advertisements for sofas and Ayn Rand and adoption laws in early colonial Bihar.Footnote ² But all history is also the history of space, and of the environment that surrounds the sofas and the laws. It is apparent, now, that “history occurs in space as well as time”.Footnote ³ Environmental history is everywhere as well as nowhere.Footnote ⁴ It is a new universal understanding, which subverts even the historians’ own anxieties about universalization: a “negative universal history”.Footnote ⁵

The symposium on History and Sustainability is the product of a workshop at the Joint Center for History and Economics at Harvard University in October 2008. Gro Harlem Brundtland, who initiated the late twentieth-century idea of sustainable development in the 1987 report of the World Commission on Environment and Development, was the first speaker, interviewed about the environment, the United Nations, and transnational environmental policy. Paul Warde spoke about ideas of durability in discourses on agriculture and forestry in early modern Europe, and Sverker Sörlin about nineteenth-century ideas of humanity as a global entity. Alison Frank described the history of unsustainability, in the rise and decline of the Galician oil industry. My own paper, on environmental capital, was about the twentieth-century idea of nature as a capital stock. There were comments by David Blackbourn, Angus Burgin, Anthony La Vopa, and Charles Rosenberg.

The meeting was part of a programme on environmental history that was started in 1994 at the Cambridge Centre for History and Economics, by Paul Warde and Meena Singh.Footnote ⁶ One of the consequences of the 2008 meeting has been a new programme on the global history of energy, at the Joint Center for History and Economics and at the MIT Research Group on History, Energy, and Environment. There is new work on the early twentieth-century projects of a geo-engineered Euro-African continent Atlantropa, by Philipp Lehmann; on tsarist and Bolshevik efforts to change the physical landscapes of Central Asia, by Maya Peterson; on the environmental and energy history of the ranching and meat-packing industry in the United States, by Joshua Specht; and on the history of artificial lights in North America, by Jeremy Zallen.Footnote ⁷

The papers in the symposium are an interesting illustration of the “new” intellectual history of the past few years, in which the history of ideas is extended to the most diverse kinds of intellectuals—theorists of coppicing and the central inspector of the Lviv–Czernowitz railway, economists and congressmen and the authors of illustrated guidebooks—and to diverse kinds of thoughts. All the papers are also influenced by the even more all-embracing prospect of an intellectual or intellectual/cultural history of the ideas of individuals who are not intellectuals. “The meanest of men has his Theory”, in Coleridge's words, and “to think at all is to theorize”.Footnote ⁸ There can be an intellectual history of low ideas, in this sense, or a history which is inspired by the techniques of intellectual history, in taking seriously languages and ideas in context. Even the history of forest wardens and itinerant oil collectors, like the history of Bohemian serfs and slaves chained in New Orleans slave markets, is a history of thought.Footnote ⁹

The new environmental history is even more embracing. Environmental history has always been a history of ideas and of imagined space.Footnote ¹⁰Changes in the Land is a history of the early American–European world of ideas about plants and animals and names, and so is The Roots of Dependency.Footnote ¹¹ But in the last decade or so of an institutional expansion in the discipline (or subdiscipline), in the US, Europe and Asia, the techniques of environmental history have been extended to ever more diverse inquiries. The multiple or variable scales which have been so important in recent historiography—shifting between the local, regional, national, transoceanic and global—were the insights, initially, of environmental historians.Footnote ¹² There is a “nascent historiographical middle ground” in early American history that “focuses on the interplay among political, economic, cultural, and biological forces”, and “by blending environmental history, transatlantic history, borderlands history, ethnohistory, and colonial studies”, extends to even the largest of political investigations: into the “potency of state power” and the “arrows of environmental and historical change”.Footnote ¹³

The romance of environmental and intellectual history is the encounter, in these auspicious circumstances, of two inclusive inquiries. It is connected to other imposing changes, and in particular to the new prospects for economic history, the history of economic thought, and the history of economic life. One of the continuing preoccupations of the “new” intellectual history (and of MIH, from its inception) has been with the history of economic ideas, and thereby—because even the highest or most theoretical economic intellectuals were concerned, since the origins of political economy, with the “medium” economic thought of public policy and the “low” economic thought of public expectations—with thoughts and ideas of different kinds.Footnote ¹⁴ The new environmental history has also, to a striking extent, been a history of traditionally economic subjects, including cities, industries, energy, land use, population and migration.

The new political or cultural or environmental history of economic life has room for individuals with ideas, expectations and memories, including ideas about distant places and metaphors of distant times. Galicia was the “Polish Baku” and the “Austrian El Dorado”, in the history recounted by Alison Frank; in Paul Warde's history of agricultural ideas, coal was “England's Peru”. The Thirlmere reservoir in the English Lake District was the site of a spectacular conflict of economic interests, as Harriet Ritvo described in The Dawn of Green, and it was also a site of political and hydraulic inspection by the engineer of the Hetch Hetchy Dam in the Californian Sierra Nevada.Footnote ¹⁵ The history of migration in Asia is in part a history of changes in ideas about climate and cultivation, as Sunil Amrith has shown, and the history of environmental change in the Malayan peninsula is in part a story of “family histories of movement, displacement, and loss”.Footnote ¹⁶ The history of the environment has been of new interest, recently, to economists and to historians of political thought.Footnote ¹⁷ It has also offered the possibility of a renewed economic history, or a new and permissive history of economic life, in which economists and historians, cultural or intellectual or political, are alike included.

These possibilities are the outcome of very large changes within historical (and economic) thought. They are the opportunities, in particular, of a postmaterialist world of the mind, in the familiar sense of going beyond the vulgar Marxian presumption of ideas as determined by material circumstances, and in the sense, too, of going beyond the other vulgar nineteenth-century presumption, of rational economic man. This is an emancipation for intellectual history, because it becomes possible to investigate the economic contexts of thought, without the anxiety that the economic is more real than the thought. It is no longer necessary, as Eric Hobsbawm pointed out in 1955, to see “ideals and movements [as] transitory and superficial, lobbying in some sense eternal and ‘real’”.Footnote ¹⁸ For environmental history, the postmaterialist world is even more emancipating. It makes possible a history of rocks and rivers and pathogens, without the anxiety that the rivers are more real—and more determining—than the individuals who live around them: a new material history.

The expansion of environmental–intellectual history is the outcome, finally, of an even larger transformation. The “negative universal history” that Dipesh Chakrabarty described in his essay “The Climate of History” was the union of the historians’ “suspicion of the universal” and the “emergent, new universal history of humans that flashes up in the moment of the danger that is climate change”: “a universal that arises from a shared sense of a catastrophe” and “calls for a global approach to politics without the myth of a global identity”.Footnote ¹⁹ The history of global environmental policy is itself an intriguing prospect for a non-national political–intellectual history, with room for the “high”, “medium” and “low” thought of public officials.Footnote ²⁰ But environmental–intellectual histories, including histories of the consumption, production and politics of energy—which are histories of how we came to live as we live now, and of the other outcomes that were possible for individuals in the past—are important to historians of other kinds as well. They are histories which are important in our own times, or our own lives.