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Doctrine of signatures

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Eyebright was used for eye infections, owing to the supposed resemblance of its flower to an eye.

The Doctrine of Signatures, also known as the Doctrine of Correspondences, states that herbs or animals have physical or behavioral traits that mirror the ailment it can successfully treat.[1] It dates from the time of Dioscorides and Galen and was popularized in the 16th and 17th centuries.[1] A theological justification, as stated by botanists such as William Coles, was that God would have wanted to show men what plants would be useful for.

This theory is a possible explanation for the ancient discovery of medicinal properties, however, there is not definitive proof as to whether the medicinal property or the connection in physical/behavioral traits was realized first.[2] The theory later became a scientific basis for trying new remedies solely based upon their qualities in an attempt to find new medicines. While there are some homeopathic remedies that are still used today which have been connected to this theory, there are also remedies from this theory which have been found harmful.[1][3] For instance, birthwort (so-called because of its resemblance to the uterus) was once used widely for pregnancies, but is carcinogenic and very damaging to the kidneys, owing to its aristolochic acid content.[4] As a defense against predation, many plants contain toxic chemicals, the action of which is not immediately apparent, or easily tied to the plant rather than other factors.

History

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The origins of the doctrine of signatures is debated by historians.[5] The concept of the doctrine of signatures dates back to Hippocratic medicine and the belief that "cures for human ills were divinely revealed in nature, often through plants."[6] The concept would be further developed by Dioscorides.[7] Dioscorides would provide ample descriptions of plant medications through various drawings, detailing the importance of their look, name, shelf life, how to tell when plants have gone bad, and how to properly harvest the crop for medical use.[7] Paracelsus (1493–1541) developed the concept further, writing that "Nature marks each growth ... according to its curative benefit", and it was further developed by Giambattista della Porta in his Phytognomonica (1588).[8]

The writings of Jakob Böhme (1575–1624) coined the term doctrine of signatures within his book The Signature of All Things (or Signatura Rerum) published in 1621.[8] He suggested that God marked objects with a sign, or "signature", for their purpose,[9] specifically that "...to that Signature, his inward form is noted in the form of his face; and thus also is a beaft [beast],an herb, and the trees; every thing as it is inwardly (in its innate vertue [virtue] and quality) fo it is outwardly figned [signed]..."[10]. Plants bearing parts that resembled human body-parts, animals, or other objects were thought to have useful relevance to those parts, animals, or objects. The "signature" could sometimes also be identified in the environments or specific sites in which plants grew.

The English physician-philosopher Sir Thomas Browne in his discourse The Garden of Cyrus (1658) uses the Quincunx pattern as an archetype of the 'doctrine of signatures' pervading the design of gardens and orchards, botany and the Macrocosm at large.

The 17th century botanist William Coles supposed that God had made 'Herbes for the use of men, and hath given them particular Signatures, whereby a man may read ... the use of them.'[8] Coles's The Art of Simpling and Adam in Eden, stated that walnuts were good for curing head ailments because in his opinion, "they Have the perfect Signatures of the Head". Regarding Hypericum, he wrote, "The little holes whereof the leaves of Saint Johns wort are full, doe resemble all the pores of the skin and therefore it is profitable for all hurts and wounds that can happen thereunto."[9]

A theological justification was made for this philosophy: "It was reasoned that the Almighty must have set his sign upon the various means of curing disease which he provided".[11]

For the late medieval viewer, the natural world was vibrant with images of the Deity: 'as above, so below,' a Hermetic principle expressed as the relationship between macrocosm and microcosm; the principle is rendered sicut in terra. Michel Foucault expressed the wider usage of the doctrine of signatures, which rendered allegory more real and more cogent than it appears to a modern eye:

Up to the end of the sixteenth century, resemblance played a constructive role in the knowledge of Western culture. It was resemblance that largely guided exegesis and the interpretation of texts; it was resemblance that organized the play of symbols, made possible knowledge of things visible and invisible, and controlled the art of representing them. (The Order of Things, p. 17)

20th century mentions of the doctrine of signatures include 5 cited publications in the 1996 Economic Botany Index (1947-1996). [2]

Remedies Linked to the Doctrine of Signatures

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Name Link to Doctrine History of Use Effectiveness
Common Figwort (Scrophulariaceae)[12][13] Figwort's roots have small nodules that resemble nodes within the lymph system or swelling.[12] Used in Spain to treat hemorrhoids, digestive conditions, respiratory, and skin conditions.[12] The treatment linked to the doctrine of signs was inflammation and conditions that cause lymph node swelling which are thought to resemble to the root nodules. [13] Treatment of symptoms related to the lymphatic system.[13] This is potentially linked to the fact that this species has iridoids which can exhibit anti-inflammatory and antioxidant properties.[14]
Eyebright aka Euphrasy/Euphrasia (Euphrasia rostkoviana)[13][15] flower blossoms resemble eyes[13][15] Used in Medieval Europe to treat conditions to do with irritated or swollen eyes like cataracts or conjunctivitis. They also were used for digestive conditions, jaundice, diabetes, and respiratory conditions. Some of these treatments are not eye related, and thus do not reflect the doctrine.[16] Contains flavonoids and polyphenols which have been linked to lowered inflammation by interacting cytokines.[16] Extracts of the plant have successfully shown antibacterial properties, specifically with gram positive bacteria. It is still used and effective within conjunctivitis[13][16] and blepharitis[16] treatments through eye drops.
Swallowwort (Papaveraceae)[13] Yellow colored latex connected to bile that is produced in the liver, stored in the gall bladder, or in some cases stomach bile.[13] In traditional Chinese medicine, this plant was used for treatment of jaundice, accumulation of fluids, or clots. In other regions it was used for ulcers, liver conditions, digestive comlplaints[17], oral infections, tuberculosis, and dermatological conditions [18] "Isoquinoline alkaloids, flavonoids, carotenoids, saponins, organic acids, and vitamins A and C are the distinct biologically active compounds of C. majus. According to the metabolites identified, it has been found to possess a range of pharmacological effects such as antimicrobial activity, anti-inflammatory, analgesic, natriuretic, antidiuretic, and anticancer effects."[18] The plant has been linked with hepatoxicity. Due to the cause of this side effect being under investigation, medicinal use in high or consistent doses is unusual due to potential health effects.[17]
Birthwort (Aristolochia clematitis)[19] Said to resemble the womb and birth canal in shape and believed to provide a good birth[19] Utilized in India, Greece, and China to induce menstruation (emmenagogues), induce labor, abortive measures, contraception, fever reduction (febrifuge), bladder stones, edemas, and gout.[20] It was also combined with quicklime and used as fish poison. [20] This plant has been linked with aristolochic acid nephropathy which can cause progressive interstitial fibrosis--a lung disease-- and bladder, kidney, or urethral cancers.[21] Specifically, it is linked to urothelial neoplasms, a precancerous cell in the urinary system.[22]
Hedge woundwort (Stachys sylvatica) [23] Believed to treat wounds and bruises because the plants themselves have holes in the leaves. [24][25] During the medieval period, flowers were ground, mixed with salt and used on spear and sword wounds.[26] [27] Both the flower and leaf extract show antibacterial and antioxidant attributes which help to control oxidative stress and risk of infection in healing.[28]
Liverwort (Marchantiophyta or Hepatica)[29] The mat forming liverworts resembled lobes of the liver.[29] "Antimicrobial, antifungal, antipyretic, antidotal activity; used to cure cuts, burns, scalds, fractures, swollen tissue, poisonous snake bites and gallstones"[30] There is some scientific support for specific species having properties which can aid treatment of hepatitis, blisters, gastrointestinal complaints, and fever. This is linked to antibacterial and antifungal properties. Liverworts also have metabolites that interact with the central nervous system and thus can have serious side effects. [31]
Lungwort (Pulmonaria officinalis)[13][19][32] The spotted leaves resemble structures within the lungs.[13] Was used in Europe to treat phthisis, another name for tuberculosis.[33] Within a 2022 systematic review of scientific research, Chauhan and associates concluded that "safety studies and clinical trials are missing for lungworts to establish most of their potential biological properties."[34]
Spleenwort (Asplenium)[35] The grass is said to resemble both hair and worms and used to treat worms or hair loss. [13][36] Usually ingested as a tea used to relieve stomach issues and parasitic worm infections in both Europe and China[36][37] As of 2021, systematic reviews of different medicinal applications showed no scientific consensus that they are effective in treating any conditions.[38] [39]
Walnuts (Juglans)[25][40][13] Believed to treat brain related conditions because seed resembles a brain or gastrointestinal complaints because of the appearance of the intestines.[25] Used to treat headaches [41][13] Walnuts contain fatty acids, which are valuable for the brain.[13] From a medicinal standpoint, there is not a significant evidence base that it can prevent cognitive decline.[42]
Lungwort was thought to have the signature of the lungs and was used to treat lung infections.

It is worth noting that it is possible that these are post hoc attributions-- the appearance and treatment linked after the medicinal property was discovered.[19] Depending on the article, remedies connected to the doctrine vary in number and consistency.

Scientific, Spiritual, and Social Context

[edit]

Signatures are often described as post hoc attributions and mnemonics used to remember the properties of a plant rather than the reason it was originally used.[43] There is no scientific or historical evidence that plant shapes and colors have aided in the discovery of their medical uses.[43]

In Europe, the idea of doctrine of signatures was linked with Christian beliefs[43]. However, similar theories were created within black magic with sympathetic magic.[44] Similar theories have been observed all over the world in ancient Egypt, China, pre-Columbian America, and the middle east.[44][43] This can also begin to explain how varied, and in some times contradictory, applications of the doctrine can be because traditional botany is subject to optimal foraging theory.[45]

Some sociologists frame the doctrine of signatures as a type of "enchantment", the idea that it is not just what one observes but how they observe it and was a device used to elevate a group of "elite" observers who could interpret the world with more accuracy.[46]

It's important to note similar, yet conflicting theories like the theory of opposites where Galen supposed that a cold and wet thing could be used to treat an imbalance in a hot and dry organ.[47] Hypotheses like these and the questions they pose, regardless of validity of the hypotheses themselves, inspired scientific investigations into the safety and usefulness of many plant based remedies.[48][49]

In literature

[edit]

The phrase "signatures of all things" appears in the beginning of episode 3 in James Joyce's novel Ulysses. The character Stephen Dedalus walking along the beach, thinking to himself "Signatures of all things I am here to read, seaspawn and seawrack, the nearing tide, that rusty boot". The Canadian poet Anne Szumigalski, 1922–1999, entitled her third full-length collection Doctrine of Signatures.

See also

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References

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Citations

  1. ^ a b c Lev, Efraim (June 2002). "The doctrine of signatures in the medieval and Ottoman Levant". Vesalius: Acta Internationales Historiae Medicinae. 8 (1): 13–22. ISSN 1373-4857. PMID 12422877.
  2. ^ a b Bennett, Bradley C. (2007-09-01). "Doctrine of Signatures: An explanation of medicinal plant discovery or Dissemination of knowledge?". Economic Botany. 61 (3): 246–255. doi:10.1663/0013-0001(2007)61[246:DOSAEO]2.0.CO;2. ISSN 1874-9364.
  3. ^ Dafni, Amots; Lev, E. (2002-12-01). "The doctrine of signatures in present-day Israel". Economic Botany. 56 (4): 328–334. doi:10.1663/0013-0001(2002)056[0328:TDOSIP]2.0.CO;2. ISSN 1874-9364.
  4. ^ Robertson, John. "Aristolochia, birthwort". The Poison Garden. John Robertson. Archived from the original on 15 March 2010. Retrieved 9 May 2022.
  5. ^ Kruse, Steven (2022-08-02). "Doctrine of Signatures Exhibition online". www.whipplemuseum.cam.ac.uk. Retrieved 2025-04-18.
  6. ^ Schmidt, Richard Penrose (1982). "Brief Comment on the Doctrine of Signatures". Literature and Medicine. 1 (1): 53–54. ISSN 1080-6571.
  7. ^ a b Porter, Roy (1999). The greatest benefit to mankind: a medical history of humanity. New York: W.W. Norton. ISBN 978-0-393-31980-4.
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  9. ^ a b Pearce, J.M.S. (May 16, 2008). "The Doctrine of Signatures" (PDF). European Neurology. 60 (1). karger.com: 51–52. doi:10.1159/000131714. PMID 18520149. S2CID 207742334. Retrieved August 31, 2008.
  10. ^ Bohme, Jakob (1621). Signatura Rerum [The Signature of All Things] (in Latin). Translated by Ellistone, John. London (published 1652).
  11. ^ White (1896), p. 38.
  12. ^ a b c Blanco-Salas, José; Hortigón-Vinagre, María P.; Morales-Jadán, Diana; Ruiz-Téllez, Trinidad (2021-07-02). "Searching for Scientific Explanations for the Uses of Spanish Folk Medicine: A Review on the Case of Mullein (Verbascum, Scrophulariaceae)". Biology Special Issue Bioactivity of Medicinal Plants and Extracts. 10 (7): 618. doi:10.3390/biology10070618. ISSN 2079-7737. Archived from the original on 2024-07-25.{{cite journal}}: CS1 maint: unflagged free DOI (link)
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  16. ^ a b c d Gruľová, Daniela; De Feo, Vincenzo (2017). "Euphrasia Rostkoviana Hayne Active Components and Biological Activity for the Treatment of Eye Disorders" (PDF). Scientific Bulletin of the Uzhhorod University – via Research Gate.
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  34. ^ Chauhan, Shweta; Jaiswal, Varun; Cho, Yeong-Im; Lee, Hae-Jeung (2022-07-01). "Biological Activities and Phytochemicals of Lungworts (Genus Pulmonaria) Focusing on Pulmonaria officinalis". Applied Sciences. 12 (13): 6678. doi:10.3390/app12136678. ISSN 2076-3417.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  35. ^ Irvine, Alexander (1860). The Phytologist: A Botanical Journal, Volume 4. William Pamplin. p. 308. As late as 1657 we find William Coles, who was a herbarist ... speaking of Spleenwort, or Miltwort, tells us that the learned Crollius, amongst the signatures of parts, doth set down Ceterach to have the signature of the spleen, and that therefore it is profitable for all diseases thereof;
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Bibliography

Further reading

[edit]
  • Boehme, Jakob (1651) Signatura Rerum (The Signature of All Things). Gyles Calvert.
--- Translation by J. Ellistone.
  • Buchanan, Scott Milross (1938) The doctrine of signatures: a defense of theory in medicine.
  • Cole, W. (1657) Adam in Eden or Nature's Paradise. J Streater for Nathanial Brooke.
  • Conrad, L.I.; M Neve, V Nutton and R Porter (1995). The Western Medical Tradition, 800 BC – 1800 AD. Cambridge University Press.
  • Porter, Roy (1997) The Greatest Benefit to Mankind: A Medical History of Humanity from Antiquity to the Present. HarperCollins.
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