Alexander von Humboldt cuts a lonely historical figure. In the years after his death he slipped rapidly out of public consciousness: from daring adventurer, pre-eminent natural historian, political progressive and all-round liberal celebrity – to yesterday’s man – largely ignored or overlooked in his native Germany and much of Europe. During his lifetime, in many parts of the world, nothing would have seemed less likely. Throughout Europe, so the approximation goes, he was as famous as Napoleon. In the United States he was dined and entertained by then-president Thomas Jefferson, who held him in the highest possible regard and with whom he sustained a lifelong correspondence. Indeed, Humboldt had a special fondness for the United States, and it is perhaps fitting that there, if anywhere, his reputation endures.

Elsewhere, however, he has slipped so far in our modern appreciation that where he does feature in contemporary debate, he is often criticised as another exploitative bourgeois adventurer, plundering distant lands for personal glory and European wealth. This is a distraction, however, and far wide of the mark. All evidence points away from this idea: he spoke out unequivocally against slavery, against colonialism, against exploitation of both land and people, and was celebrated for doing so amongst the populations of the countries that came to define the rest of his life.

Humboldt (1769-1859) was born into a wealthy German family, the son of a retired general. Although fascinated by the natural world from a very early age, he seemed destined to follow his older brother into a political career. His education and early employment pointed in that direction, but increasingly he developed a passion for travel. He became close friends with Georg Foster, a companion of James Cook on his second voyage to the Pacific, and thereafter actively pursued a career committed to the scientific understanding of the natural world, studying commerce and foreign languages at Hamburg with a view to international travel, and taking exploratory trips around Europe through the 1790s.

In 1799, after months of delay, frustration and forcibly changed plans caused by the politics surrounding the end of the French Revolution and Napoleon’s rise to power, he sailed for Latin America at the start of a five-year expedition with Aime Bonpland that would define the rest of his life. Despite later forays into Russia and a career in the diplomatic service, it was the data he collected and the ideas he formed while in South and Central America that engaged his intellect until his death. On his return from America in 1804 he was a celebrity Europe-wide, and gave voice to a theory of science that has never found equivalence.

Humboldt understood and viewed science in a manner unique among his contemporaries and perhaps from any of his successors. His years in South and Central America fostered in him a world-view that whilst attempting to make sense of the world scientifically, did so in a manner wholly unparalleled in the scientific community.

It may be fair to characterise Humboldt thus: that rather than approaching an understanding of the natural world from the ground up, his natural inclination was to attempt to see things from the top down. His search was for generalities. For systems. For the ways that forces of nature met, interacted with, challenged and changed one another. Rather than approaching species as fixed and particular entities in specific environments, he was concerned with how ecosystems as a whole came into being, and how they and their constituent parts altered over time. He questioned how plants adapted as the landscape and climate shifted, how animal species changed with the plants, and how the structure and behaviour of the plants themselves ‘evolved’ over time. For Humboldt, everything was constant interaction and interrelation: a vision of the world as unified, fundamentally inter-determined and in permanent flux.

And yet his revolutionary ideas failed to spark a revolution: no paradigm has revolved around his vision: science did not follow in Humboldt’s path. This failure of the scientific community to take on more of Humboldt’s ideas can be brought down to two specific facts. The first is that despite total commitment to what we have described as the scientific method, he was in outlook and ultimate objective so unlike any other scientist; his aims were so large and out-of-keeping with contemporary paradigmatic scientific thought that it seems almost as if his contemporaries did not quite know what to do with his ideas. Amidst a culture so committed to the idea of labelling and categorisation, Humboldt himself simply failed to be pinned down. Nobody could quite get a handle on him, and hence his ideas and convictions failed to take solid root. Scientists could admire and attempt to emulate or follow Humboldt, but to do so was to tread a path seen only by him. In Humboldt’s footsteps there was a tendency to lose one’s way.

The second reason for the fall-from-prominence of Humboldt and his ideas was the great event of 19th century science, which followed only a few months after Humboldt’s death in 1859. This was the publication of On the Origin of Species. Darwin’s debt to Humboldt is clear and uncontroversial, and Darwin himself was well aware of it – admiring his scientific method, his overarching vision, as well as the poetic and lucid descriptions of the far-off worlds he encountered. He wrote frequently in his correspondence from the Beagle of his admiration for and indebtedness to Humboldt, and the two exchanged letters that convey a very genuine sense of mutual respect and admiration. Darwin’s work undoubtedly drew on many of the facts and ideas that Humboldt discovered and proposed, but he was able to form a coherent theory that not only explained environmental interrelation, but was able to explain natural history in broadly universal scientific terms. Albeit that Darwin’s work was itself poetic, speculative and radical – it was also authentically and recognisably scientific, and his theory seemingly complete. It was an immediate sensation within the scientific community, and the ideas it contained swiftly spread throughout the public, and certain now-familiar terms began to enter the common vernacular.

It seems that from very early on, Humboldt had some notion of what the younger scientist might achieve. In a letter to Darwin from 1839, he wrote:

You told me in your kind letter that, when you were young, the manner in which I studied and depicted nature in the torrid zones contributed toward exciting in you the ardour and desire to travel in distant lands. Considering the importance of your work, Sir, this may be the greatest success that my humble work could bring. Works are of value only if they give rise to better ones.

Scientific revolutions are usually not the work of one scientist, and although Humboldt’s work inspired and helped to shape the Darwinian revolution that followed it, the science that was practised thereafter by no means encompassed his idea of the world: it was far narrower than that. Humboldt transcended the paradigm of his age, in pursuit of a vision that nobody else has yet been able to follow.

Artwork by JMC.