Carl Linnaeus
PHILOSOPHIA BOTANICA
Translated by Stephen Freer
402pp. Oxford University Press. Paperback, £35.00.
0 19 856934 3
In 1771, the Scottish naturalist William Smellie used an article in the first edition of the Encyclopaedia Britannica (of which he was the main compiler) to attack the “alluring seductions” of the Linnaean system of plant classification. Smellie accused Linnaeus of taking his analogies “beyond all decent limits”, claiming that the Swedish naturalist’s books were enough to make even the most “obscene romance writer” blush. His outrage was shared by the English naturalist William Goodenough, who was appalled by Linnaeus’s “disgusting names, his nomenclatural wantonness, vulgar lasciviousness, and the gross prurience of his mind”.
The subject of all this moral outrage was the methodus propria (“proper method”) of plant classification, devised by the Swedish naturalist Carl von Linné, better known by the Latinized version of his name as Linnaeus. His system was published in a series of books that started appearing in the 1750s, the most important of which were the Philosophia Botanica (“Philosophy of Botany”, 1751) and the Species Plantarum (“Species of Plants”, 1753). These provided the foundations for all subsequent classification, not least because the two-part Latin scientific names, such as Homo sapiens, that we still use were regularized and – even more importantly – publicized by Linnaeus.
Before Linnaeus’s work, classificatory systems varied widely across Europe. The earliest ones for plants were devised by the medical practitioners of the ancient world, and usually grouped and named plants according to their uses, such as which part of the body they were suitable for curing. During the Renaissance, Andrea Cesalpino, prefect of the Pisa botanic garden, tried to reclassify plants independently of the uses to which humans put them by attempting to judge the degree of perfection which their flowers, fruits and roots had attained. This produced a scale, from the lowly (because fruitless) mushroom to the most complex flowering plants. Yet this arrangement was still based on human standards of perfection, so Gaspard Bauhin, director of the Basel botanic garden, wrote a universal history of plants (the Panax), which he hoped would reveal their true relations, the underlying order that he and other naturalists dimly perceived to be embedded in nature itself.
In the seventeenth century, the challenge of uncovering the long-sough natural system was taken up by Joseph Pitton de Tournefort in Paris and John Ray in Cambridge. Ray realized that most classifications – especially those used by herbalists – were still artificial, based on human perceptions of what plants were good for. He and Tournefort were both convinced that there must be a natural alternative, and although Ray was a Protestant and Tournefort a Catholic, they both agreed that what “natural” really meant was “divinely ordained”.
The idea that there must be a true natural system was based on the observation that some plants appear more closely related to one another than they are to others. That which we call a rose, for example, is similar to an apple tree; one only has to look at their flattish, five-petalled flowers to see that. By contrast, a sunflower is more similar to a daisy than it is to a rose or its relatives. Such broad groupings seem self-evident, based on the overall similarities between the plants, but finer distinctions are harder to make. For example, nothing like an apple’s fruit grows on a rose bush, and so the apple (and its relatives) have usually been classified into a separate group within the larger family that comprises the rose and its relatives, but a layperson might have some trouble deciding which fruits belong in which sub-families (or, indeed, even in recognizing a rose hip as a fruit in the vernacular sense). As one moves from seemingly obvious wider categories, like “rose” and “apple”, down to the precise distinctions needed to separate one genus (such as Rosa) from another (such as Rubus, the blackberry genus, which is a member of the same sub-family), the work gets harder. And it gets harder still as you attempt to do the same for species (such as distinguishing Rosa canina, the dog rose, from Rosa eglanteria, the eglantine under which Titania slept). And inevitably as the distinctions get finer, disagreements begin; just how much difference is needed to make a species, compared with the amount needed to define a genus?
Tournefort and Ray each had their own answers to these questions, as, indeed, did virtually every botanist in Europe. Each separated plants into slightly different groups and – even more worryingly – gave them different names. A botanical Babel resulted. Some botanists stuck to their own native language’s plant names, ensuring that the same plant was known by half-a-dozen different names, which effectively prevented botanists from different countries understanding each other. Endless, time-consuming confusion resulted whenever naturalists tried to exchange plants or information about them. In an effort to avoid such misunderstandings, some naturalists stuck with the widely understood classical languages, but either coined their own names for plants, or applied long, descriptive labels that were supposed to make it explicit which plant they were talking about, but were cumbersome to use and almost impossible to remember. The need for a common language became increasingly urgent as Europeans travelled further afield, conquering and collecting as they went. Ray noted that while Aristotle’s pupil Theophrastus had named only 500 plants, Bauhin’s Panax contained 6,000, while Ray’s own work extended to more than twice as many species as Bauhin’s. That exponential growth continued unabated into the eighteenth century, and was one of the major reasons why Linnaeus decided he had to reform the system of classification.
The other powerful motivator was money. From pepper to timber, cotton to sugar, hemp to opium, plants were extremely lucrative – and it was costing Sweden a fortune to import the vast variety of exotic plant-based items that her wealthier citizens were demanding. Before Adam Smith started selling the myth that free trade enriched everyone, many Europeans – including Linnaeus – believed that their nations were suffering a bullion drain: all their gold and silver was being sent to Asia to pay for silks, spices, tea and similar luxuries. If this continued, Europe would eventually be reduced to nothing more than a series of impoverished Asian colonies. This worried Swedes especially, since their country had few gold and silver mines, and their access to the open oceans was blocked by its neighbours, Denmark and Norway. There seemed to be no way for Sweden to acquire valuable overseas colonies, so Linnaeus felt they must instead strive for self-sufficiency, acquiring and growing the plants they needed. As he told the Swedish Academy of Science, “if Oaks did not grow in Sweden, and some mortal wanted to get Oaks into [the country] . . . wouldn’t he serve his country more than if with the sacrifice of many thousands of people he added a Province to Sweden?”.
The economic doctrine that shaped Linnaeus’s thinking was known as cameralism, a name that derives from the Latin camera, a room – the room in question being a treasure chamber. The cameralists’ main concern was to ensure that more treasure entered the chamber than left it, hence the concern about the bullion drain. Such worries motivated Linnaeus’s acclimatization experiments – he was hoping that plants from warmer countries could be gradually fooled into tolerating the harsher Swedish climate. He tried rice, coffee, sugar cane, ginger and olive trees. They all died, yet he yearned for still more exotic crops: “should coconuts chance to come into my hands”, he wrote, “it would be as if fried Birds of Paradise flew into my throat when I opened my mouth”. These nationalistic ambitions drove the Linnaean reform: what was the point of obtaining some rare and valuable plant from the other side of the world, only to discover it was simply some common Swedish weed under another name?
With all this in mind, Linnaeus synthesized Ray’s careful delineation of species with Tournefort’s work on genera. He then built on the German botanist Rudolph Jakob Camerarius’s discovery that plants reproduced sexually, which provided an apparently natural basis for Cesalpino’s focus on flowers as the basis of classification. Linnaeus then combined Cesalpino’s system with the two-part Latin names, which we now call Linnaean binomials but which were first used by Bauhin. As the historian Richard Drayton argues, despite his enormous importance, Linnaeus was a synthesizer rather than an original thinker: his work combined 200 years of European botanical thinking, in an effort to bring order to three centuries of European expansion.
Like his precursors, Linnaeus sought the true natural system; by taking the machinery of nature apart, he hoped to recover the blueprint its Creator had used to build it. “This”, as he wrote in the Philosophia Botanica, “is the beginning and the end of what is needed in botany.” Yet, by his own admission, he failed, offering his readers only “fragments” of the divine harmony. Years, perhaps generations, of further work would, he thought, be needed to complete what he had begun, and in the mean time, there were those ever-growing piles of the world’s plants to sort out and acclimatize.
The methodus propria was designed to be so easy to apply that it would remove the ambiguities inherent in lengthy descriptions. To use it, all one had to do was count: the number of stamens (the flower’s male parts) determined its class, while the pistils, or carpels (the female parts) fixed its order. Equipped with Linnaeus’s books, a novice could learn to identify plants in minutes, while the learned could fit the novelties of the world into an existing order. Any plant – whether an exotic African or a familiar wildflower – that had two stamens, belonged unambiguously to the class “Diandria”, and if it also possessed one carpel it fitted into the subsidiary order “Monogynia”. There was a place for everything and, thanks to the tireless voyages of Linnaeus’s pupils and disciples, soon everything would be in its place.
The names of the Linnaean classes and orders were derived from the Greek aner, aman or husband, and gyne, woman or wife. Linnaeus took the implications of his names literally, describing the flowers as “bridal beds”, which were “perfumed with so many soft scents”, to spur the floral groom to “embrace his beloved bride and offer her his gifts”. The key to the sexual system, as the method inevitably became known, was the nuptiae plantarum, the marriages of plants. But few plants have one stamen and one carpel, so in most cases the Linnaeans found themselves describing the most disgraceful orgies, in which groups of “brides” fell lewdly into the embraces of whole armies of “husbands”.
The simplicity of the sexual system made it extremely popular, as did its erotic connotations – at least in the eyes of some readers. It inspired Erasmus Darwin to write a book-length poem, “The Botanic Garden”, in which he not only retained Linnaeus’s sexual metaphors but proudly claimed that, with English a more direct language than Latin, he had been able to make his translations even more “expressive and concise” than the originals. Which perhaps explains his book’s popularity. But while such matters might be suitable subjects for educated gentlemen to read about, Smellie and Goodenough were worried about other readers. The simplicity of Linnaeus’s system was making it increasingly popular and accessible; that troubled the self-appointed guardians of horticultural morals because botany was thought to be a most appropriate science for women to study and to introduce their children to. Linnaeus’s frank insistence on the sexual nature of plants seemed entirely inappropriate for these audiences; his success in popularizing and democratizing botany was precisely what created opposition.
Reading this excellent translation of the Philosophia Botanica by Stephen Freer, it is impossible to understand what the fuss was about. Linnaeus presented his system in the form of brief aphorisms – such as “No sane person introduces primitive generic names”. He then expanded on these with a couple of sentences condemning what he calls “barbaric” names (those not derived from Greek or Latin), because “they are from languages not understood by the learned”. His example was the fern genus Osmunda, which is derived from the old English Christian name, Osmund (a variant of Edmund that is almost unheard of these days, but the scientific name is still in use, despite the great Swede’s disapproval). Hardly the kind of thing to excite today’s censorious moralists. However, if readers looking for titillation are likely to be disappointed by this book, historians, botanists and gardeners are among those who will find it fascinating. Not only does Linnaeus set out the basic rules that are still in use; he gives a great many practical details of how to describe, measure and preserve plants, as well as of how to organize a botanical outing or site a greenhouse.
