On the morning of 29 January 1842, Charles Darwin, then 32 years old and still almost 20 years removed from publishing Origin of Species, had been called upon to attend a personal meeting with Alexander von Humboldt through a mutual friend in London. Then 72 years old and one of the most celebrated scientists in Europe, Humboldt was a fount of knowledge on natural history and well known to deploy his erudition dexterously in small settings as well as on large stages.
When Darwin arrived at the house in Belgrave Square to meet Humboldt, he was prepared with a litany of questions on plant distribution and species migration. He left three hours later dumbfounded and dismayed – the elder scientist’s flow of words barely stopped to allow Darwin to speak, let alone develop lines of inquiry into matters of interest. For three long hours Humboldt chattered away, cheerfully but endlessly, “beyond all reason”, as Darwin later put it.
This curious episode hints at the challenge of characterizing Humboldt’s towering contributions to scientific knowledge. The historian must navigate multiple disciplines in arts and science, each with their own respective histories, in at least four languages. The historian, unlike Darwin, must get a word in edgewise.
Many of the figures who appear alongside Humboldt in historian Andrea Wulf’s 2015 book, The Invention of Nature, as his predecessors, contemporaries, or proteges known to posterity through their mastery of some specific field of creativity or industry. Histories of evolution, geology, and statecraft, for example, cannot be written without reference to the accomplishments of Darwin, Lyell, and Jefferson. Somewhat like Gottfried Leibniz, another imposing and rather underappreciated genius of European civilization, Humboldt’s tireless productivity — and he was still working on the fifth volume of his Cosmos series when he died, just shy of his 90th birthday — the wide range of his interests, and his appearance at the birth of so many nascent fields of inquiry have made it challenging for historians and the public to get the measure of him.
Indeed, Wulf’s task is daunting. Her efforts to humanize Humboldt, to understand his work in its context, and the subsequent legacy of his ideas deserve high praise. Her strategy in doing so is to argue that there is a uniquely Humboldtian approach to understanding nature. The Humboldtian approach may be summarized simply in two claims. The first is that every force of nature is interlaced and connected, and the second is that these forces should be perceived with both the head and the heart. Both of these claims might appear self-evidently true to modern readers with a stake in ecology, the environment, or natural history. But they, too, have histories; they were contested, defended, and controversial in Humboldt’s time. They were hard-won. Wulf persuasively places Humboldt at the centre of them.
To illustrate the novel quality of Humboldt’s idea of a single complexly interwoven web of life, Wulf foregrounds wider debates around the classification system of Linnaeus, the proto-evolutionary and evolutionary ideas of Darwin and his contemporaries, and 19th-century assumptions about progress. The master concept throughout, for Humboldt, is dynamic change. Whereas the Linnaean approach to botany was based on counting and categorizing the plant’s physical characteristics to determine its relationship to other plants and to the system as a whole, Humboldt categorized them into geographical zones and regions. To understand the characteristics of plants as influenced by their respective environments — to “read” nature in this way — reveals “a global force behind nature, the movements of civilizations as well as of landmass.”
The implications of this were not, of course, lost on the young Darwin, and one of the most arresting features of The Invention of Nature is the manner in which Wulf digs out the marginalia in Darwin’s notes — and there are “several hundred references to Humboldt in Darwin’s manuscripts” – creating a kind of dialogue between the two men. It reveals a younger scientist gripped by Humboldt’s way of thinking. If, as Humboldt insisted, bodies of land and water moved, if temperatures fluctuated over time, if the earth itself was changing, then it stands to reason that all plants and animals have also been subject to change. Darwin was then sorting through his findings on his great Beagle voyage, thinking about common ancestry, and on the verge of formulating the theory of natural selection.
Even more to the point, if the environment changes over time, it must also be true that the environment can be destroyed. Humboldt said as much repeatedly and explicitly berated European governments for not only the cruelty of certain of their colonial policies but also for the exemplary carelessness they exhibited for its environmental impacts. For Wulf, this life-long conviction of Humboldt’s, stated and restated in so many iterations, must be his greatest gift to posterity. It spoke to the 19th century observer’s sense of optimism, “with progress as the century’s watchword”, when “no one worried that nature itself might be destroyed”. It also speaks to the 21st-century observer’s faith in technological solutions to environmental problems created by human beings.
Humboldt was so successful at embedding the idea that nature is a single unified system of dynamic forces into the fabric of European and North American intellectual life because he understood that the web is not only interwoven with us but also within us. This is the second claim of the Humboldtian worldview, that nature, when properly channeled and understood, is something felt and experienced deeply and personally that stimulates the imagination as well as the intellect. In this, Humboldt carried Goethe’s spirit and genius with him.
Although Goethe is remembered today for his poetry, he was also an amateur scientist, and he impressed upon the younger Humboldt the dramatic power of understanding, thinking, and talking about nature as a source of beauty, imagination, and consolation. As Goethe’s Faust himself says, the profound truths of nature will not yield to the crude “screw and levers” of the empiricist, and there are other deeper mysteries that connect us to nature and to the universe. He filled his books with detailed illustrations, lyrical descriptions of sea sands, rising suns, riverbanks, and “the glowing womb of the earth”, teeming with plants and animals all dependent on each other. “With an aesthetic breeze”, Goethe remarked, Humboldt lit science into a “bright flame”.
Wulf even speculates that the poetry of the Humboldtian worldview so affected Darwin that the last paragraph of Origin of Species, in which he contemplates the life and history of a single entangled bank — surely also among the finest examples of English-language prose, scientific or otherwise — was inspired in part by a specific passage from Humboldt’s Personal Narrative. Wulf’s book is replete with examples of Humboldt’s influence on his contemporaries. He delivered free lectures about poetry, astronomy, geology, and landscape painting to packed, diverse, mixed-gender audiences in Berlin. He was one of Europe’s most famous and influential public figures for 50 years. He was probably the first popularizer of science.
Wulf’s proposals for Humboldt’s claims for the attention of modern readers vary in their persuasiveness. References to climate change feel laboured and anachronistic, and it is not a term that Humboldt coined or would have recognized. He mournfully recorded the harmful effects of deforestation in South America, for example, and proposed it would create additional waves of destruction, including the evaporation of rivers and the disappearance of brush-wood. But he did not arrive at “climate change” as we understand it today. Wulf remarks in the prologue that Humboldt was “far ahead of his time”. This phrase, as always, stands no test — it is less anachronistic and truer to say that Humboldt was, in fact, of his time but possessing a rather exceptional faculty for insight into it.
Humboldt’s accomplishments are so extensive they are in no need of inflating. It is enough to understand him, his ideas, and his context and to establish his place in the history of science. But Humboldt’s story is also partly about restoring meaning and perspective to why we perceive nature as an ecological system, why we feel connected to it in mysterious ways, and why we should feel moved to protect it. From this angle, and thanks to Wulf, Humboldt appears very much like our contemporary.