The Invention of Nature (5 page)

Goethe’s house in Weimar (Illustration Credit 2.2)

His favourite place, though, was his Garden House near the River Ilm, outside the old city walls on the duke’s estate. Just a ten-minute walk from his main residence, this small cosy house had been his first home in Weimar, but now it was his refuge where he withdrew from the continuous stream of visitors. Here he wrote, gardened or welcomed his most intimate friends. Vines and sweet-scented honeysuckle climbed along the walls and windows. There were vegetable plots, a meadow with fruit trees and a long path lined with Goethe’s beloved hollyhocks. When Goethe had first moved there in 1776, he had not only planted his own garden but had also convinced the duke to transform the castle’s formal baroque garden into a fashionable English landscape park where irregularly planted groves of trees gave a natural feel.

Goethe ‘was getting tired of the world’. The Reign of Terror in France had turned the initial idealism of the 1789 revolution into a bloody reality of mass executions of tens of thousands of so-called enemies of the revolution. This brutality, along with the ensuing violence that the Napoleonic Wars spread across Europe, had disillusioned Goethe, putting him in the ‘most melancholic mood’. As armies marched through Europe, he worried about the threats that faced Germany. He lived like a hermit, he said, and the only thing that kept him going was his scientific studies. Science for him was like a ‘plank in a shipwreck’.

Today Goethe is famed for his literary works but he was a passionate scientist too, fascinated by the formation of the earth as well as botany. He had a rock collection that eventually numbered 18,000 specimens. As Europe descended into war, he quietly worked on comparative anatomy and optics. In the year of Humboldt’s first visit, he established a botanical garden at the University of Jena. He wrote an essay, the Metamorphosis of Plants, in which he argued that there was an archetypal, or primordial, form underlying the world of plants. The idea was that each plant was the variation of such an urform. Behind variety was unity. According to Goethe, the leaf was this urform, the basic shape from which all others had developed – the petals, the calyx and so on. ‘Forwards and backwards the plant is always nothing but leaf,’ he said.

These were exciting ideas, but Goethe had no scientific sparring partner with whom to develop his theories. All that changed when he met Humboldt. It was as if Humboldt ignited the spark that had been missing for so long. When Goethe was with Humboldt, his mind worked in all directions. He pulled out old notebooks, books and drawings. Papers piled up on the table as they discussed botanical and zoological theories. They scribbled, sketched and read. Goethe was not interested in classification but in the forces that shaped animals and plants, he explained. He distinguished between the internal force – the urform – that provided the general form of a living organism and the environment – the external force – that shaped the organism itself. A seal, for example, had a body adapted to its sea habitat (the external force), Goethe said, but at the same time its skeleton displayed the same general pattern (the internal force) as those of land mammals. Like the French naturalist Jean-Baptiste Lamarck and later Charles Darwin, Goethe recognized that animals and plants adapted to their environment. The urform, he wrote, could be found in all living organisms in different stages of metamorphosis – even between animals and humans.

Listening to Goethe talk with such breathless enthusiasm about his scientific ideas, Humboldt advised him to publish his theories on comparative anatomy. And so Goethe began to work at a frenzied pace, spending the early morning hours dictating to an assistant in his bedroom. Still in bed, propped up on pillows and wrapped in blankets to keep out the cold, Goethe worked more intensely than he had for years. There wasn’t much time because by 10 a.m. Humboldt arrived and their discussions continued.

It was during this period that Goethe began to fling both his arms around whenever he went for a walk – provoking alarmed glances from his neighbours. He had discovered, he finally explained to a friend, that this exaggerated swinging of one’s arms was a remnant from the four-legged animal – and therefore one of the proofs that animals and humans had a common ancestor. ‘That’s how I walk more naturally,’ he said, and couldn’t have cared less if Weimar society regarded this rather strange behaviour as unrefined.

Over the next few years, Humboldt regularly travelled to Jena and Weimar whenever he found time. Humboldt and Goethe went on long walks and dined together. They conducted experiments and inspected the new botanical garden in Jena. An invigorated Goethe moved easily from one topic to another: ‘early morning corrected poem, then anatomy of frogs’ was a typical entry in his diary during one of Humboldt’s visits. Humboldt was making him dizzy with ideas, Goethe told a friend. He had never met anyone so versatile. Humboldt’s drive, Goethe said, ‘whipped the scientific things’ with such speed that it was sometimes hard to follow.

Three years after his first visit, Humboldt arrived in Jena for a three-month break. Once again Goethe joined him there. Instead of going back and forth to Weimar, Goethe moved to his rooms at the Old Castle in Jena for a few weeks. Humboldt wanted to conduct a long series of experiments on ‘animal electricity’ because he was trying to finish his book on the subject. Almost every day – often with Goethe – Humboldt walked the short distance from his brother’s house to the university. He spent six or seven hours in the anatomy theatre as well as lecturing on the subject.

When a violent thunderstorm hit the area one warm spring day, Humboldt dashed outside to set up his instruments in order to measure the electricity in the atmosphere. As the rain lashed down and thunder reverberated across the fields, the small town was illuminated by a wild dance of lightning. Humboldt was in his element. The next day, when he heard that a farmer and his wife had been killed by the lightning, he rushed over to obtain their corpses. Laying out their bodies on the table in the round anatomy tower, he analysed everything: the man’s leg bones looked as if they had been ‘pierced by shotgun pellets!’, Humboldt noted excitedly, but the worst damage was to the genitals. At first he thought that the pubic hair might have ignited and caused the burns, but dismissed the idea when he saw the couple’s unharmed armpits. Despite the increasingly putrid smell of death and burned flesh, Humboldt enjoyed every minute of this gruesome investigation. ‘I cannot exist without experiments,’ he said.

Humboldt’s favourite experiment was one that he and Goethe discovered together by chance. One morning Humboldt placed a frog’s leg on a glass plate and connected its nerves and muscles to different metals in sequence – to silver, gold, iron, zinc and so on – but generated only a discouraging gentle twitch in the leg. When he then leaned over the leg in order to check the connecting metals, it convulsed so violently that it leapt off the table. Both men were stunned, until Humboldt realized that it had been the moisture of his breath that had triggered the reaction. As the tiny droplets in his breath had touched the metals they had created an electric current that had moved the frog’s leg. It was the most magical experiment he had ever carried out, Humboldt decided, because by exhaling on to the frog’s leg it was as if he were ‘breathing life into it’. It was the perfect metaphor for the emergence of the new life sciences.

In this context they also discussed the theories of Humboldt’s former professor, Johann Friedrich Blumenbach, about the forces that shaped organisms – the so-called ‘formative drive’ and ‘vital forces’. Fascinated, Goethe then applied these ideas to his own about the urform. The formative drive, Goethe wrote, triggered the development of certain parts in the urform. The snake, for example, has an endlessly long neck because ‘neither matter nor force’ had been wasted on arms or legs. By contrast, the lizard has a shorter neck because it also has legs, while the frog has an even shorter neck because its legs are longer. Goethe then went on to explain his belief that – contrary to Descartes’s theory that animals were machines – a living organism consisted of parts that only function as a unified whole. To put it simply, a machine could be dismantled and then assembled again, while the parts of a living organism worked only in relation to each other. In a mechanical system the parts shaped the whole while in an organic system the whole shaped the parts.

Humboldt widened this concept. And although his own theories of ‘animal electricity’ were eventually proved wrong, they did give him the foundation of what would become his new understanding of nature.1 Whereas Blumenbach and other scientists applied the idea of forces to organisms, Humboldt applied them to nature on a much broader level – interpreting the natural world as a unified whole that is animated by interactive forces. This new way of thinking changed his approach. If everything was connected, then it was important to examine the differences and similarities without ever losing sight of the whole. Comparison became Humboldt’s primary means of understanding nature, not abstract mathematics or numbers.

Goethe was captivated, reporting to his friends how much he admired the young man’s intellectual virtuosity. It was telling that Humboldt’s presence in Jena coincided with one of Goethe’s most productive phases in years. Not only did he join Humboldt in the anatomy tower but Goethe was also composing his epic poem Hermann and Dorothea and returning to his theories on optics and colour. He examined insects, dissected worms and snails and continued his studies in geology. His days and nights were now occupied with work. ‘Our little academy’, as Goethe called it, was very busy. Wilhelm von Humboldt was working on a verse translation of one of Aeschylus’s Greek tragedies which he discussed with Goethe. With Alexander, Goethe set up an optical apparatus to analyse light and investigated the luminescence of phosphor. In the afternoons or evenings they sometimes met at Wilhelm’s and Caroline’s house but more often assembled at Friedrich Schiller’s house on the market square, where Goethe recited his poems and others presented their own work until late at night. Goethe was so exhausted that he admitted to almost looking forward to a few peaceful days in Weimar ‘to recover’.

Alexander von Humboldt’s pursuit of knowledge was so infectious, Goethe told Schiller, that his own scientific interests had been woken from hibernation. Schiller, though, worried that Goethe was being pulled too far away from poetry and aesthetics. All this was Humboldt’s fault, Schiller believed. Schiller also thought that Humboldt would never accomplish anything great because he dabbled in too many subjects. Humboldt was only interested in measurements and, despite the richness of his knowledge, his work displayed a ‘poverty of meaning’. Schiller remained a lone, negative voice. Even the friend he confided in disagreed: yes, Humboldt was enthusiastic about measurements but these were the building blocks for his wider understanding of nature.

After a month in Jena, Goethe returned to Weimar but quickly missed his new-found stimulation and immediately invited Humboldt to visit. Five days later Humboldt arrived in Weimar and stayed for a week. The first evening Goethe kept his guest to himself but on the next day they had lunch at the castle with Karl August followed by a big dinner party at Goethe’s house. Goethe showed off what Weimar had to offer: he took Humboldt to see the landscape paintings in the duke’s collections, as well as some geological specimens that had just arrived from Russia. Almost every day they went for meals at the castle, where Karl August invited Humboldt to conduct some experiments to entertain his guests. Humboldt had to oblige but he thought the time spent at court was utterly wasted.

For the next month, until Humboldt’s final departure from Jena, Goethe commuted between his house in Weimar and his rooms in the castle in Jena. They read natural history books together, and went out for long walks. In the evening they shared meals and reviewed the latest philosophical texts. They now often met at Schiller’s newly bought Garden House, just outside the city walls. Schiller’s garden was bordered by a little river at the back where the men sat in a small arbour. A round stone table in the middle was laden with glasses and plates of food but also with books and papers. The weather was glorious and they enjoyed the mild early summer evenings. At night, they could only hear the gurgling of the stream and the song of the nightingale. They talked about ‘art, nature and the mind’, as Goethe wrote in his diary.

Schiller (left) with Wilhelm and Alexander von Humboldt and Goethe in Schiller’s garden in Jena (Illustration Credit 2.3)

The ideas they discussed were engaging scientists and thinkers across Europe: the question of how to understand nature. Broadly speaking, two schools of thought vied for dominance: rationalism and empiricism. Rationalists tended to believe that all knowledge came from reason and rational thought, while the empiricists argued that one could ‘know’ the world only through experience. Empiricists insisted that there was nothing in the mind that had not come from the senses. Some went so far as to say that at birth the human mind was like a blank piece of paper without any preconceived ideas – and that over a lifetime it filled up with knowledge that came from sensory experience alone. For the sciences this meant that the empiricists always had to test their theories against observations and with experiments, while the rationalists could base a thesis on logic and reason.

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.