The Invention of Nature

A few years before Humboldt first met Goethe, the German philosopher Immanuel Kant had declared a philosophical revolution that he had boldly claimed was as radical as that of Copernicus some 250 years previously. Kant took up a position between rationalism and empiricism. The laws of nature as we understand them, Kant wrote in his famous Critique of Pure Reason, only existed because our mind interpreted them. Just as Copernicus had concluded that the sun couldn’t be moving around us, so, Kant said, we had to completely change our understanding of how we made sense of nature.

The dualism between the external and the internal world had preoccupied philosophers for millennia. It was a question that asks: Is the tree that I’m seeing in my garden the idea of that tree or the real tree? For a scientist such as Humboldt who was trying to understand nature, this was the most important question. Humans were like citizens of two worlds, occupying both the world of the Ding an sich (the thing-in-itself) which was the external world, and the internal world of one’s perception (how things ‘appeared’ to individuals). According to Kant, the ‘thing-in-itself’ could never be truly known, while the internal world was always subjective.

What Kant brought to the table was the so-called transcendental level: the concept that when we experience an object, it becomes a ‘thing-as-it-appears-to-us’. Our senses as much as our reason are like tinted spectacles through which we perceive the world. Though we may believe that the way we order and understand nature is based on pure reason – upon classification, the laws of motion and so on – Kant believed that this order was shaped by our mind, through those tinted spectacles. We impose this order on nature, and not nature upon us. And with this the ‘Self’ became the creative ego – almost like a lawgiver of nature even if it meant that we could never have a ‘true’ knowledge of the ‘thing-in-itself’. The result was that the emphasis was shifting towards the Self.

There was more that interested Humboldt. One of Kant’s most popular lecture series at the university in Königsberg (today’s Kaliningrad in Russia but then part of Prussia) was on geography. Over forty years, Kant taught this lecture series forty-eight times. In his Physische Geographie, as the series was called, Kant insisted that knowledge was a systematic construct in which individual facts needed to fit into a larger framework in order to make sense. He used the image of a house to explain this: before constructing it brick by brick and piece by piece, it was necessary to have an idea of how the entire building would look. It was this concept of a system that became the linchpin of Humboldt’s later thinking.

There was no avoiding these ideas in Jena – everybody was talking about them – with one British visitor remarking that the small town was the ‘most fashionable seat of the new philosophy’. Goethe admired Kant and had read all his works and Wilhelm was so fascinated that Alexander worried his brother would ‘study himself to death’ over the Critique of Pure Reason. One of Kant’s pupils, who was teaching at Jena University, told Schiller that within the next century Kant would be as famous as Jesus Christ.

What interested those in the Jena circle most was this relationship between the internal and the external world. Ultimately it led to the question: How is knowledge possible? During the Enlightenment the internal and the external world had been regarded as two entirely separate entities, but later English Romantics such as Samuel Taylor Coleridge and American Transcendentalists such as Ralph Waldo Emerson would declare that man had once been one with nature – during a long vanished Golden Age. It was this lost unity that they strove to restore, insisting that the only way to do so was through art, poetry and emotions. According to the Romantics, nature could only be understood by turning inwards.

Humboldt was immersed in Kant’s theories and would later keep a bust of the philosopher in his study, calling him a great philosopher. Half a century later, he would still say that the external world only existed in so far as we perceived it ‘within ourselves’. As it was shaped inside the mind, so did it shape our understanding of nature. The external world, ideas and feelings ‘melt into each other’, Humboldt would write.