became a widely accepted cure for kidney stones . Over SHORT COMMUNICATION time, such ‘sympathetic magic’ would develop into rec- ognizable medical systems such as Ayurveda and Unani Cataloguing nature’s ‘library’: and, in Western belief, into a ‘Doctrine’ of Signatures . The doctrine of signatures in Western thought and practice Cataloguing Nature’s ‘Library’ The earliest humans most probably derived information Owen Durant about plants from observing animals . Their proximity to and total reliance on their surroundings for nourish- Abstract ment and medicine made it important that they could Generally viewed as a quaint, if puzzling, relic of the recognize signs of sickness and cure . folk medical tradition, the Doctrine of Signatures and Zoopharmacognosy, the branch of science that wider concepts of ‘sympathetic magic’ have informed seeks to understand animals’ self-medication, particu- selection patterns of natural medicines the world over . larly in the primate kingdom, has identified ‘strong sim- Associations between form and perceived medical value ilarities’ in plant selection criteria between humans and are idiosyncratic and culture specific . Briefly considered chimpanzees 1. here are the factors that led to the development of a Notable is the shared use of rough leaves of certain Doctrine of Signatures in the western tradition and Ficus species for the alleviation of pain associated with what lessons it might impart when re-considered as an intestinal parasites . evolving series of ideas, rather than as a single doctrine . Selection criteria such as leaf texture, smell and taste have no doubt contributed to recognition of medicinal Introduction attributes and are, in certain ways, easier to identify Faced with a multitude of unfamiliar and often danger- than perceived physical resemblance to an organ 2. ous plants that potentially held the keys to life and However, these qualities are still subject to a wide spec- death, our ancestors needed ways to map and distin- trum of interpretation . guish the helpful and harmful from the merely ineffec- How can perceptual and often esoteric impressions tual . One such way was to ascribe meaning to an ob- be objectively assessed? The answer may be, simply, that ject’s shape, colour, location, smell or taste–seeking they cannot be studied bio-scientifically 3. Calling the ‘clues’ from these characteristics to indicate likely me- Doctrine of Signatures ‘largely untestable’ Bennett, dicinal purpose . nevertheless, attempted a meta-analysis of botanical no- For example, a plant resembling a lung (e .g . Pulmo- menclature, looking at the descriptive suffix cordata naria officinalis L ). could be used to treat respiratory (heart) to investigate whether this suffix corresponded illness; red coloured plants (e g. Vinca rosea L ). might to instances of reported cardiac therapeutic use . Using be used to cure blood conditions; plants found near a a sample of some 80 plant binomials he found there to river (e .g . Salix alba L ). could be beneficial in the treat- be no significant correlation . However, the attempt to ment of water-borne diseases . At the same time, sweet link what are known to be subjective descriptions to smelling (e .g . Acorus spp ). or bitter tasting plants (e g. medicinal use can only paint a partial picture at best . Momordica charantia L ). could be used to combat dis- Bennett concluded, among other things, that signatures eases attributed to excessive bitterness (e g. Kidney or acted as a mnemonic (memory aiding) device and Spleen disorders) or excessive sweetness (e .g . Diabetes) . should be regarded as ‘post hoc attributions rather than By finding similarities, patterns or signatures would a priori clues’ to plant use . emerge which could guide foragers and be passed into I would suggest, with the necessity for communica- collective knowledge . Some even believed that plants tion over generations, signatures represent something spoke to them in hallucenogenic rituals (e .g . Ayahuasca) more systematized than mere memory aids . Unable to conveying secrets of their curative powers . document their pharmacopoeia, pre-literate societies Even animal parts and fossils were believed to pos- learned to ‘read’ plants and these signatures evolved to sess healing properties that could be inferred from their function as ‘catalogue numbers’ in a natural ‘library’ . outward appearance . Traditions as diverse as the Scan- How these ‘catalogue numbers’ were determined dinavian and the Native American record the use of Elk’s and assigned would, of course, vary - according to time, hoof as a remedy for ‘falling sickness’ (epilepsy) based place and culture . For example, Pulmonaria officinalis on the Elk’s behavior of using its hoof to relieve itself L ,. (lungwort), present in the northern United States, from ‘vertigo’; the kidney shaped Jew’s Stone (Lapis ju- popular in Europe as a respiratory medicine and astrin- daicus) which appears in Discorides’ De Materia Medica gent, has no recorded medicinal use in North America . PHARMACEUTICAL HISTORIAN · 2017 · Volume 47/4 95 In contrast, Scutellaria lateriflora L., (skullcap), a native (Genesis 30:14-16) where the anthropomorphic man- of North America, known to be anti-convulsive and drake (Figure 1) appears as an aphrodisiac and cure for sedative in the European pharmacopeia has no equiva- impotence . The concept re-surfaces in Franciscan Friar lent Native American medicinal use 4,. 5 Albertus Magnus’ De Mineralibus (c . 1260) and the first natural history encyclopedia, Hortus Sanitatis Religion and Reformation (1484) . The ‘Doctrine’ of Signatures itself is, according to the In the febrile climate of Reformation-era Europe, American Anthropologist Daniel E . Moerman, a ‘Eu- the Doctrine of Signatures remained something in ropean’ idea . Porter (2006) believes that the Doctrine which Christians could still agree . The writings of reli- of Signatures ‘evolved gradually over the centuries’ 6. gious mystics, such as Jakob Böhme (1575-1624) con- Dyer (1889) wrote that the Doctrine of Signatures was cerning cosmic signatures, would foreshadow the ‘new ‘a development of the much older notion of a real con- age’ worldview with its emphasis on the intrinsic unity nection between object and image’ 7. Duffin (2008) of nature . Although the term signature implicitly sug- states that the Doctrine of Signatures’ roots are ‘firmly gests an author and Creator, Böhme’s ideas, in particu- based on Aristotelian principles’ .8 lar, are closer to the Eastern ones of Hinduism and Bud- dhism with their concepts of prana and qi - a ‘life force’ permeating everyone and everything . Figure 2. Plants of the Asteracae family; one of multiple plates in della Porta’s Phytognomica (1588) (Source: The Wellcome Library) Figure 1. Illustration of mandrake from a fifteenth cen- tury Northern Italian herbal (author unknown) In 1588 the Italian polymath Giambattista della (Source: Schoenberg Institute for Manuscript Studies at Porta (1535-1615) published the influential Phytogno- University of Pennsylvania Libraries) monica which bridged the gulf between animism and rationalism . With its systematically juxtaposed images of body and plant parts (Figure 2) Phytognomonica dis- In many respects the Doctrine of Signatures fits plays evidence of a proto-scientific method .9 Indeed, for more comfortably into the realm of religion rather than della Porta, true Natural Magick (as opposed to sor- science . Some of the earliest recorded references to the cery), was ‘nothing else but the survey of the whole Doctrine of Signatures are found in the Old Testament course of nature’ 10. 96 PHARMACEUTICAL HISTORIAN · 2017 · Volume 47/4 A Curious Paradox systems (e.g. Traditional Chinese Medicine or TCM) At its core, the Doctrine of Signatures presents a pro- which are of growing popular interest in the West and are, found conundrum . Hippocrates (460-370 BC) codified increasingly, the focus of serious ethnopharmacological the prevailing medical opinion of his time with the ob- studies which demonstrate the integrity of traditional servation: similia similibus curentur (by similar things healing categories and the superior reliability of ethno- are the sick made healthy); yet, a parallel, but seeming- pharmacologically based drug leads . 15,16,17 ly diametrically opposed, notion of contraria contrariis In the same way that attempts to justify the Doc- remedium (opposites cure opposites) found its expres- trine of Signatures have been labelled as examples of sion in the later Galenic model . Both incorporated rem- post hoc attribution, our evaluation - of a doctrine - rath- edies based on a Doctrine of Signatures-like rationale er than of the disparate ideas which it contains could and this led to the formation of two distinct branches be seen in a similar light; a fundamental misunder- of homeopathic and antipathic medical practice . standing clouded by history . So, how do we reconcile these two linked but ap- Perhaps, it is now time we stopped viewing the Doc- parently contradictory practices? I would argue that trine of Signatures as a doctrine at all, but rather a series clues can be found in the much earlier Vedic concept of interwoven, but distinct, ethnomedical concepts of nirdvandva (cf . Carl Jung) or the transcending of op- which, given a more sympathetic interpretation, could posites; the ‘oneness’ of creation rendering distinctions pass the insight of previous generations into our hands . and, therefore, opposites obsolete 11. Stripped of dogma, the Doctrine of