Editing Doctrine of signatures

{{Short description|Ancient herbalist theory}}
[[File:Euphrasia rostkoviana ENBLA02.jpeg|thumb|250px|[[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.<ref name=":0">{{Cite journal |last=Lev |first=Efraim |date=June 2002 |title=The doctrine of signatures in the medieval and Ottoman Levant |url=https://pubmed.ncbi.nlm.nih.gov/12422877/ |journal=Vesalius: Acta Internationales Historiae Medicinae |volume=8 |issue=1 |pages=13–22 |issn=1373-4857 |pmid=12422877}}</ref> Theological justifications, such as that of botanist William Cole, were that God would want to show men what plants would be useful for.<ref name="ScienceMus" /> The doctrine of signatures has a debated origin.<ref name=":3">{{Cite web |last=Kruse |first=Steven |date=2022-08-02 |title=Doctrine of Signatures Exhibition online |url=https://www.whipplemuseum.cam.ac.uk/news/doctrine-signatures-exhibition-online |access-date=2025-04-18 |website=www.whipplemuseum.cam.ac.uk |language=en}}</ref> Many historians believe it begins with primitive thinking methods, while other historians believe it originated with [[Dioscorides]] and was popularized in the 16th and 17th centuries after [[Jakob Böhme]] coined the doctrine of signatures in his book ''The Signature of All Things''.<ref name="ScienceMus" /><ref name=":3" /><ref name=":2" /> 

This theory is a possible explanation for the ancient discovery of medicinal properties; however, there is no definitive proof as to whether the medicinal property or the connection in physical/behavioral traits was realized first.<ref name=":1">{{Cite journal |last=Bennett |first=Bradley C. |date=2007-09-01 |title=Doctrine of Signatures: An explanation of medicinal plant discovery or Dissemination of knowledge? |url=https://link.springer.com/article/10.1663/0013-0001(2007)61%5B246:DOSAEO%5D2.0.CO;2 |journal=Economic Botany |language=en |volume=61 |issue=3 |pages=246–255 |doi=10.1663/0013-0001(2007)61[246:DOSAEO]2.0.CO;2 |issn=1874-9364|url-access=subscription }}</ref> 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.<ref name=":0" /><ref>{{Cite journal |last1=Dafni |first1=Amots |last2=Lev |first2=E. |date=2002-12-01 |title=The doctrine of signatures in present-day Israel |url=https://link.springer.com/article/10.1663/0013-0001(2002)056%5B0328:TDOSIP%5D2.0.CO;2 |journal=Economic Botany |language=en |volume=56 |issue=4 |pages=328–334 |doi=10.1663/0013-0001(2002)056[0328:TDOSIP]2.0.CO;2 |issn=1874-9364|url-access=subscription }}</ref> 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.<ref>{{cite web |url=http://www.thepoisongarden.co.uk/atoz/aristolochia_clematitis.htm |title=Aristolochia, birthwort |last=Robertson |first=John |website=The Poison Garden |publisher=John Robertson |access-date=9 May 2022 |archive-url=https://web.archive.org/web/20100315060407/http://www.thepoisongarden.co.uk/atoz/aristolochia_clematitis.htm |archive-date=15 March 2010 |url-status=dead}}</ref> 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 ==
[[File:Illustration_of_doctrine_of_signatures_from_Ars_Magna_Lucis_Et_Umbrae.jpg|thumb|253x253px|Diagram by [[Athanasius Kircher]] describing the relationship of the human body, constellations, and plants with signatures for medical use]]
The origins of the doctrine of signatures are debated by historians.<ref>{{Cite web |last=Kruse |first=Steven |date=2022-08-02 |title=Doctrine of Signatures Exhibition online |url=https://www.whipplemuseum.cam.ac.uk/news/doctrine-signatures-exhibition-online |access-date=2025-04-18 |website=www.whipplemuseum.cam.ac.uk |language=en}}</ref> 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."<ref>{{Cite journal |last=Schmidt |first=Richard Penrose |date=1982 |title=Brief Comment on the Doctrine of Signatures |url=https://muse.jhu.edu/article/376928/pdf |journal=Literature and Medicine |volume=1 |issue=1 |pages=53–54 |doi=10.1353/lm.2011.0208 |issn=1080-6571|url-access=subscription }}</ref> The concept would be further developed by [[Pedanius Dioscorides|Dioscorides]].<ref name=":2">{{Cite book |last=Porter |first=Roy |title=The greatest benefit to mankind: a medical history of humanity |date=1999 |publisher=W.W. Norton |isbn=978-0-393-31980-4 |location=New York}}</ref> 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.<ref name=":2" /> [[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).<ref name="ScienceMus" />

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.<ref name="ScienceMus">{{cite web |url=http://www.sciencemuseum.org.uk/broughttolife/techniques/doctrine.aspx |title=Doctrine of Signatures |publisher=Science Museum |access-date=February 8, 2014 |archive-date=January 3, 2014 |archive-url=https://web.archive.org/web/20140103201719/http://www.sciencemuseum.org.uk/broughttolife/techniques/doctrine.aspx |url-status=dead }}</ref> He suggested that God marked objects with a sign, or "signature", for their purpose,<ref name=Pearce>{{cite journal |url=http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowPDF&ArtikelNr=131714&Ausgabe=237347&ProduktNr=223840&filename=131714.pdf |journal=European Neurology |date=May 16, 2008
| author=Pearce, J.M.S. |publisher=karger.com |title=The Doctrine of Signatures |access-date=August 31, 2008 |doi=10.1159/000131714 |pmid=18520149 |volume=60 |issue=1 |pages=51–52|s2cid=207742334 |doi-access=free }}</ref> specifically that "to that Signature, his inward form is noted in the form of his face; and thus also is a beast, an herb, and the trees; every thing as it is inwardly [in its innate virtue and quality] so it is outwardly signed".<ref>{{Cite book |last=Bohme |first=Jakob |title=Signatura Rerum |year=1621 |location=London |publication-date=1652 |language=Latin |translator-last=Ellistone |translator-first=John |trans-title=The Signature of All Things}}</ref> 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."<ref name=ScienceMus/> 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."<ref name=Pearce/>

In the late 19th century, [[Andrew Dickson White]] published his book ''History of the Warfare of Science with Theology in Christendom'', which pushed back against the doctrine of signatures.<ref name=":4">{{Cite book |last=White |first=Andrew Dickson |url=https://archive.org/details/cu31924022599330/page/n5/mode/1up |title=A history of the warfare of science with theology in Christendom |date=1896 |publisher=New York, D. Appleton and company |others=Cornell University Library}}</ref> White explains the connectiveness between Christianity and the doctrine of signatures as its increased presence and significance in the orthodox faith as theological pseudoscience.<ref name=":4" /> White further explains how the doctrine of signatures developed into the church as a justification to "[disgust] the demon with the body which he tormented" and how "the patient was made to swallow or apply to himself various unspeakable ordures", with various uses of animal organs as medications to protect against demons.<ref name=":4" />

For the late medieval viewer, the natural world was vibrant with images of the Deity: '[[as above, so below]]', a [[Hermeticism|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:
{{blockquote|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)}}Late 20th-century mentions of the doctrine of signatures include five cited publications in the 1996 Economic Botany Index (1947–1996).<ref name=":1" /> In the early 21st century, Amots Dafni and Efraim Lev conducted a survey and used literature to understand how the doctrine of signatures has evolved in the Middle East.<ref name=":11" /> Their studies show that the doctrine of signatures evolved into four main categories: "similarity of the plant or plant organ to the damaged human organ, similarity to animal shape or behavior, similarity of plant color to the color of the disease's symptoms or the medical phenomena, and similarity of plant habitat or characteristic to human features."<ref name=":11">{{Cite journal |last1=Dafni |first1=Amots |last2=Lev |first2=E. |date=2002 |title=The Doctrine of Signatures in Present-Day Israel |url=https://www.jstor.org/stable/4256605 |journal=Economic Botany |volume=56 |issue=4 |pages=328–334 |doi=10.1663/0013-0001(2002)056[0328:TDOSIP]2.0.CO;2 |jstor=4256605 |issn=0013-0001|url-access=subscription }}</ref>

== Linked remedies ==
{| class="wikitable"
|+
!Name
!Link to doctrine
!History of use
!Effectiveness
|-
|[[Scrophularia nodosa|Common figwort]] ([[Scrophulariaceae]])<ref name=":13">{{Cite journal |last1=Blanco-Salas |first1=José |last2=Hortigón-Vinagre |first2=María P. |last3=Morales-Jadán |first3=Diana |last4=Ruiz-Téllez |first4=Trinidad |date=2021-07-02 |title=Searching for Scientific Explanations for the Uses of Spanish Folk Medicine: A Review on the Case of Mullein (Verbascum, Scrophulariaceae) |journal=Biology |language=en |volume=10 |issue=7 |pages=618 |doi=10.3390/biology10070618 |doi-access=free |pmid=34356473 |pmc=8301161 |issn=2079-7737 }}</ref> [[File:Scrophularia capillaris.jpg|center|thumb|242x242px|Sample of ''Scrophularia capillaris'' and root structure]]
|Figwort's roots have small nodules that resemble nodes within the lymph system or swelling.<ref name=":13" />
|Used in Spain to treat hemorrhoids, digestive conditions, respiratory conditions, and skin conditions.<ref name=":132">{{Cite journal |last1=Blanco-Salas |first1=José |last2=Hortigón-Vinagre |first2=María P. |last3=Morales-Jadán |first3=Diana |last4=Ruiz-Téllez |first4=Trinidad |date=2021-07-02 |title=Searching for Scientific Explanations for the Uses of Spanish Folk Medicine: A Review on the Case of Mullein (Verbascum, Scrophulariaceae) |journal=Biology |language=en |volume=10 |issue=7 |pages=618 |doi=10.3390/biology10070618 |doi-access=free |pmid=34356473 |pmc=8301161 |issn=2079-7737 }}</ref> In ancient China, ''[[Scrophularia ningpoensis]]'', another member of the Scrophulariaceae family, was used for sore throats, abscesses, carbuncles, and constipation.<ref>{{Cite journal |last1=Ren |first1=Dan |last2=Shen |first2=Zhan-yun |last3=Qin |first3=Lu-ping |last4=Zhu |first4=Bo |date=2021-04-06 |title=Pharmacology, phytochemistry, and traditional uses of Scrophularia ningpoensis Hemsl |url=https://linkinghub.elsevier.com/retrieve/pii/S0378874120335765 |journal=Journal of Ethnopharmacology |volume=269 |pages=113688 |doi=10.1016/j.jep.2020.113688 |pmid=33338592 |issn=0378-8741|url-access=subscription }}</ref> Native American women in the Shenandoah Valley would use this plant after childbirth to prevent bleeding and cramps or as a calming tonic.<ref>{{Cite book |last1=Simpson |first1=Ann |url=https://books.google.com/books?id=tChfEAAAQBAJ&dq=Scrophulariaceae+doctrine&pg=PP1 |title=Wildflowers of Shenandoah National Park: A Field Guide to the Park's Wildflowers |last2=Simpson |first2=Rob |date=2022-07-01 |publisher=Rowman & Littlefield |isbn=978-1-4930-6031-3 |language=en}}</ref> The treatment linked to the doctrine of signs was for inflammation and conditions that cause lymph node swelling, which are thought to resemble the root nodules.<ref>{{Cite book |last=Graves |first=Julia |url=https://books.google.com/books?id=8ybT6QU1l3gC&q=figwort&pg=PT12 |title=The Language of Plants: A Guide to the Doctrine of Signatures |date=2012 |publisher=Steiner Books |isbn=978-1-58420-103-8 |language=en}}</ref>
|Study of this plant has correlated it with anti-inflammatory effects.<ref name=":133">{{Cite journal |last1=Blanco-Salas |first1=José |last2=Hortigón-Vinagre |first2=María P. |last3=Morales-Jadán |first3=Diana |last4=Ruiz-Téllez |first4=Trinidad |date=2021-07-02 |title=Searching for Scientific Explanations for the Uses of Spanish Folk Medicine: A Review on the Case of Mullein (Verbascum, Scrophulariaceae) |journal=Biology |language=en |volume=10 |issue=7 |pages=618 |doi=10.3390/biology10070618 |doi-access=free |pmid=34356473 |pmc=8301161 |issn=2079-7737 }}</ref> This is potentially linked to the fact that this species has [[iridoid]]s, which can exhibit anti-inflammatory and antioxidant properties.<ref>{{Cite journal |last1=Thabet |first1=Amany A. |last2=Ayoub |first2=Iriny M. |last3=Youssef |first3=Fadia S. |last4=Al-Sayed |first4=Eman |last5=Efferth |first5=Thomas |last6=Singab |first6=Abdel Nasser B. |date=2022-08-01 |title=Phytochemistry, structural diversity, biological activities and pharmacokinetics of iridoids isolated from various genera of the family Scrophulariaceae Juss. |journal=Phytomedicine Plus |volume=2 |issue=3 |pages=100287 |doi=10.1016/j.phyplu.2022.100287 |issn=2667-0313|doi-access=free }}</ref>
|-
|[[Euphrasia|Eyebright]] aka Euphrasy/Euphrasia (''[[Euphrasia rostkoviana]]'')<ref name="ScienceMus2">{{cite web |title=Doctrine of Signatures |url=http://www.sciencemuseum.org.uk/broughttolife/techniques/doctrine.aspx |url-status=dead |archive-url=https://web.archive.org/web/20140103201719/http://www.sciencemuseum.org.uk/broughttolife/techniques/doctrine.aspx |archive-date=January 3, 2014 |access-date=February 8, 2014 |publisher=Science Museum}}</ref> [[File:Euphrasia stricta kz10.jpg|center|thumb|226x226px|Euphrasia flower]]
|Named "eyebright" because its flower blossoms resemble eyes.<ref name="ScienceMus2" />
|Used in medieval Europe to treat conditions that have 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.<ref name=":32">{{Cite journal |last1=Gruľová |first1=Daniela |last2=De Feo |first2=Vincenzo |date=2017 |title=Euphrasia Rostkoviana Hayne Active Components and Biological Activity for the Treatment of Eye Disorders |url=https://www.researchgate.net/publication/320102226 |journal=Scientific Bulletin of the Uzhhorod University |via=Research Gate}}</ref>
|Contains [[flavonoid]]s and [[polyphenol]]s, which have been linked to lowered inflammation by interacting with [[cytokine]]s.<ref name=":32" /> Extracts of the plant have successfully shown antibacterial properties, specifically with [[gram-positive bacteria]]. It is still used and effective within [[conjunctivitis]]<ref name=":32" /> and [[blepharitis]]<ref name=":32" /> treatments through eye drops.
|-
|Swallowwort ([[Papaveraceae]])<ref>{{Cite book |last=Wood |first=Matthew |url=https://books.google.com/books?id=Czw-DwAAQBAJ&dq=Chelidonium+%22doctrine+of+signatures%22&pg=PR9 |title=The Book of Herbal Wisdom: Using Plants as Medicines |date=2017-12-19 |publisher=North Atlantic Books |isbn=978-1-62317-124-7 |language=en}}</ref> [[File:Chelidonium majus 4 RF.jpg|center|thumb|Swallowwort plant|208x208px]]
|Linked through animal behavior, "some say that this [the name] was because it flowered at about the time the swallows reappeared and finished when they left; but there grew a story that swallow mothers bathed their blind nestlings with its [figwort's] juices to help them see."<ref>{{Cite book |last=Hart-Davies |first=Christina |url=https://books.google.com/books?id=dxf7EAAAQBAJ&q=nestling&pg=PP1 |title=The Herbal Year: Folklore, History and Remedies |date=2024-04-02 |publisher=Yale University Press |isbn=978-0-300-26586-6 |language=en}}</ref><ref>{{Cite book |last=Leyel |first=C. F. |url=https://books.google.com/books?id=8kz6q3Alkm4C&q=swallow&pg=PA11 |title=Cinquefoil |date=2007 |publisher=Health Research Books |isbn=978-0-7873-1413-2 |language=en}}</ref><ref>{{Cite book |last=Richardson |first=Rosamond |url=https://books.google.com/books?id=sFAmEAAAQBAJ&q=swallowwort&pg=PT4 |title=Britain's Wild Flowers: A Treasury of Traditions, Superstitions, Remedies and Literature |date=2017-04-13 |publisher=National Trust |isbn=978-1-911358-34-3 |language=en}}</ref> Swallowwort may also be referred to as celandine (species ''[[Chelidonium majus]]'' in the family Papaveraceae), and this is cited as being linked to the doctrine because of the yellow latex believed to link with jaundice and liver bile.<ref>{{Cite book |last=Wood |first=Matthew |url=https://books.google.com/books?id=Czw-DwAAQBAJ&dq=Chelidonium+%22doctrine+of+signatures%22&pg=PR9 |title=The Book of Herbal Wisdom: Using Plants as Medicines |date=2017-12-19 |publisher=North Atlantic Books |isbn=978-1-62317-124-7 |language=en}}</ref>
|In traditional Chinese medicine, this plant was used for the treatment of jaundice, accumulation of fluids, or clots. In other regions it was used for ulcers, liver conditions, digestive complaints,<ref name=":52">{{Cite journal |last1=Pantano |first1=Flaminia |last2=Mannocchi |first2=Giulio |last3=Marinelli |first3=Enrico |last4=Gentili |first4=S. |last5=Graziano |first5=Silvia |last6=Busardò |first6=F. P. |last7=Di Luca |first7=Natale Mario |date=2017 |title=Hepatotoxicity induced by greater celandine (Chelidonium majus L.): a review of the literature |url=https://iris.uniroma1.it/handle/11573/968547 |journal=European Review for Medical and Pharmacological Sciences |volume=21 |issue=1 |pages=46–52}}</ref> oral infections, tuberculosis, and dermatological conditions.<ref name=":42">{{Cite journal |last1=Kwon |first1=Haejin |last2=Sathasivam |first2=Ramaraj |last3=Yoon |first3=Jiwon |last4=Park |first4=Chanung |last5=Park |first5=Nam Il |last6=Chung |first6=Yong Suk |last7=Park |first7=Sang Un |date=2024-03-01 |title=Expression Analysis of Phenylpropanoid Pathway Genes and Phenylpropanoid Accumulation in Different Organs of Chelidonium majus L. |journal=Natural Product Communications |language=EN |volume=19 |issue=3 |pages=  |doi=10.1177/1934578X241239835 |issn=1934-578X|doi-access=free }}</ref>
|"[[Isoquinoline alkaloids]], flavonoids, [[carotenoid]]s, [[saponin]]s, 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."<ref name=":42" /> The plant has been linked with [[hepatotoxicity]]. 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.<ref name=":52" />
|-
|Birthwort (''[[Aristolochia clematitis]]'')<ref name=":03">{{Cite journal |last=Durant |first=Owen |date=2017-12-01 |title=Cataloguing nature's 'library': The doctrine of signatures in Western thought and practice |url=https://www.ingentaconnect.com/content/bshp/ph/2017/00000047/00000004/art00004 |journal=Pharmaceutical Historian |volume=47 |issue=4 |pages=95–98}}</ref> [[File:Aristolochia clematitis 002.JPG|center|thumb|184x184px|''Aristolochia clematitis'']]
|Said to resemble the womb and birth canal in shape and believed to provide a good birth.<ref name=":03" />
|Utilized in India, Greece, and China to induce menstruation ([[emmenagogue]]s), induce labor, abortive measures, contraception, fever reduction ([[febrifuge]]), bladder stones, edemas, and gout.<ref name=":6">{{Cite journal |last1=Scarborough |first1=John |last2=Fernandes |first2=Andrea |date=2011 |title=Ancient Medicinal Use of Aristolochia: Birthwort's Tradition and Toxicity |url=https://www.jstor.org/stable/23645794 |journal=Pharmacy in History |volume=53 |issue=1 |pages=3–21 |jstor=23645794 |pmid=22702021 |issn=0031-7047}}</ref> It was also combined with quicklime and used as fish poison.<ref name=":6" />
|This plant has been linked with [[aristolochic acid]] [[Kidney disease|nephropathy]], which can cause [https://www.thoracic.org/education-center/ild/pdf/2020_ats_pf-ild_v13_web.pdf progressive interstitial fibrosis]—a lung disease—and bladder, kidney, or urethral cancers.<ref>{{Citation |last1=Nortier |first1=Joëlle L. |title=Aristolochic Acid Nephropathy and Balkan Nephropathy |date=2022 |work=Tubulointerstitial Nephritis |pages=207–216 |editor-last=Atta |editor-first=Mohamed G. |url=https://link.springer.com/chapter/10.1007/978-3-030-93438-5_16 |access-date=2025-04-18 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-93438-5_16 |isbn=978-3-030-93438-5 |last2=Vanherweghem |first2=Jean-Louis |last3=Jelakovic |first3=Bojan |editor2-last=Perazella |editor2-first=Mark A.|url-access=subscription }}</ref> Specifically, it is linked to urothelial neoplasms, a precancerous cell in the urinary system.<ref>{{Citation |last1=Stegelmeier |first1=Bryan L. |title=Chapter 7 - Poisonous Plants |date=2023-01-01 |work=Haschek and Rousseaux' s Handbook of Toxicologic Pathology (Fourth Edition) |pages=489–546 |editor-last=Haschek |editor-first=Wanda M. |url=https://linkinghub.elsevier.com/retrieve/pii/B9780443161537000071 |access-date=2025-04-21 |publisher=Academic Press |doi=10.1016/b978-0-443-16153-7.00007-1 |isbn=978-0-443-16153-7 |last2=Davis |first2=T. Zane |editor2-last=Rousseaux |editor2-first=Colin G. |editor3-last=Wallig |editor3-first=Matthew A. |editor4-last=Bolon |editor4-first=Brad|url-access=subscription }}</ref>
|-
|[[Hedge woundwort]] (''Stachys sylvatica'')<ref>{{cite web |author=McDougal, Kevin |date=2013 |title=Hedge Woundwort |url=http://www.incredible-edible-todmorden.co.uk/apothecary/hedge-woundwort |url-status=dead |archive-url=https://web.archive.org/web/20131215110138/http://www.incredible-edible-todmorden.co.uk/apothecary/hedge-woundwort |archive-date=December 15, 2013 |access-date=February 8, 2014}}</ref> [[File:Stachys sylvatica 3 RF.jpg|center|thumb|''Stachys sylvatica'']]
|Believed to treat wounds and bruises because the plants themselves have holes in the leaves.<ref>{{Cite journal |last=Bagli |first=Marco |date=2021 |title=Wort Plant Names in Contemporary English |url=https://ricerca.unistrapg.it/handle/20.500.12071/45068?mode=simple |journal=Iperstoria |issn=2281-4582}}</ref><ref name=":7">{{Cite book |last=Hughes |first=Jon G. |url=https://books.google.com/books?id=GolgEAAAQBAJ&dq=woundwort+%22doctrine+of%22&pg=PT4 |title=Witches, Druids, and Sin Eaters: The Common Magic of the Cunning Folk of the Welsh Marches |date=2022-09-20 |publisher=Simon and Schuster |isbn=978-1-64411-429-2 |language=en}}</ref>
|During the medieval period, flowers were ground, mixed with salt, and used on spear and sword wounds.<ref>{{Cite book |last=Barnes |first=Simon |url=https://books.google.com/books?id=TZxZEAAAQBAJ&dq=woundwort+%22doctrine+of%22&pg=PT3 |title=The History of the World in 100 Plants |date=2022-10-27 |publisher=Simon and Schuster |isbn=978-1-3985-0549-0 |language=en}}</ref><ref>{{Cite book |last=Brown |first=Michael |url=https://books.google.com/books?id=ZWuEEAAAQBAJ&q=woad |title=Medieval Plants and their Uses |date=2022-12-02 |publisher=White Owl |isbn=978-1-5267-9459-8 |language=en}}</ref>
|Both the flower and leaf extract show antibacterial and antioxidant attributes, which help to control [[oxidative stress]] and risk of infection in healing.<ref>{{Cite journal |last1=Ouerfelli |first1=Manel |last2=Majdoub |first2=Nesrine |last3=Aroussi |first3=Jihen |last4=Almajano |first4=María Pilar |last5=Bettaieb Ben Kaâb |first5=Leila |date=2021-09-01 |title=Phytochemical screening and evaluation of the antioxidant and anti-bacterial activity of Woundwort (Anthyllis vulneraria L.) |url=https://link.springer.com/article/10.1007/s40415-021-00736-6 |journal=Brazilian Journal of Botany |language=en |volume=44 |issue=3 |pages=549–559 |doi=10.1007/s40415-021-00736-6 |bibcode=2021BrJBo..44..549O |issn=1806-9959|hdl=2117/356661 |hdl-access=free }}</ref>
|-
|Liverwort ([[Marchantiophyta]] or ''[[Hepatica]]'')<ref name=":8">{{Cite book |last=Wilbraham |first=Joanna |url=https://books.google.com/books?id=zfRGEQAAQBAJ&dq=liverwort+%22doctrine+of%22&pg=PP1 |title=Mosses, Liverworts, and Hornworts of the World: A Guide to Every Order |date=2025-08-05 |publisher=Princeton University Press |isbn=978-0-691-26877-4 |language=en}}</ref> [[File:Illustration.Hepatica nobilis.jpg|center|thumb|Illustration of Hepatica plant|268x268px]]
|The mat-forming liverworts resembled lobes of the liver.<ref name=":8" />
|"Antimicrobial, antifungal, antipyretic, antidotal activity; used to cure cuts, burns, scalds, fractures, swollen tissue, poisonous snake bites and gallstones".<ref>{{Cite journal |last1=Jacek |first1=Drobnik |last2=Adam |first2=Stebel |date=2021 |title=Four Centuries of Medicinal Mosses and Liverworts in European Ethnopharmacy and Scientific Pharmacy: A Review |url=https://www.mdpi.com/2223-7747/10/7/1296 |journal=Plants |language=en |volume=10 |issue=7 |doi=10.3390/plant |doi-broken-date=25 April 2025 |doi-access=free |issn=2223-7747 |archive-url=http://web.archive.org/web/20250207003405/https://www.mdpi.com/2223-7747/10/7/1296 |archive-date=2025-02-07}}</ref>
|There is some scientific support for specific species having properties that 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.<ref>{{Cite journal |last1=Bandyopadhyay |first1=Anustup |last2=Dey |first2=Abhijit |date=2022-05-01 |title=The ethno-medicinal and pharmaceutical attributes of Bryophytes: A review |journal=Phytomedicine Plus |volume=2 |issue=2 |pages=100255 |doi=10.1016/j.phyplu.2022.100255 |issn=2667-0313|doi-access=free }}</ref>
|-
|[[Lungwort]] (''Pulmonaria officinalis'')<ref name=":03" /><ref name="Birmingham">{{cite web |title=The Tudors |url=http://www.birminghambotanicalgardens.org.uk/wp-content/uploads/2009/10/tudors.pdf |url-status=usurped |archive-url=http://web.archive.org/web/20210904213217/http://www.birminghambotanicalgardens.org.uk/wp-content/uploads/2009/10/tudors.pdf |archive-date=4 September 2021 |access-date=11 November 2014 |publisher=Birmingham Botanical Gardens}}</ref> [[File:Pulmonaria officinalis 800.jpg|center|thumb|192x192px|Lungwort plant]]
|The spotted leaves resemble structures within the lungs.{{cn|date=April 2025}}
|Was used in Europe to treat [[Phthisis pulmonalis|phthisis]], another name for tuberculosis.<ref>{{Cite journal |date=1873 |title=The Doctrine Of Signatures |url=https://www.jstor.org/stable/25233757 |journal=The British Medical Journal |volume=1 |issue=627 |pages=19 |jstor=25233757 |issn=0007-1447}}</ref>
|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."<ref>{{Cite journal |last1=Chauhan |first1=Shweta |last2=Jaiswal |first2=Varun |last3=Cho |first3=Yeong-Im |last4=Lee |first4=Hae-Jeung |date=2022-07-01 |title=Biological Activities and Phytochemicals of Lungworts (Genus Pulmonaria) Focusing on Pulmonaria officinalis |journal=Applied Sciences |language=en |volume=12 |issue=13 |pages=6678 |doi=10.3390/app12136678 |doi-access=free |issn=2076-3417}}</ref>
|-
|[[Spleenwort]] (''Asplenium'')<ref>{{cite book |last1=Irvine |first1=Alexander |url=https://books.google.com/books?id=u8cgAQAAMAAJ |title=The Phytologist: A Botanical Journal, Volume 4 |date=1860 |publisher=William Pamplin |page=308 |quote=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;}}</ref> [[File:Asplenium viride RF.jpg|center|thumb|177x177px|''Spleenwort'' plant]]
|The grass is said to resemble both hair and worms and is used to treat worms or hair loss.<ref name=":9">{{Cite book |url=https://doi.org/10.52305/zdnj1623 |title=Ferns: Growth, Diversity and Ecological Importance |date=2023 |publisher=Nova Science Publishers |doi=10.52305/zdnj1623 |isbn=979-8-88697-554-3 |editor-last=Kumar Srivastava |editor-first=Shobhit |editor-last2=Prakash Srivastava |editor-first2=Gyan}}</ref>
|Usually ingested as a tea used to relieve stomach issues and parasitic worm infections in both Europe and China.<ref name=":9" /><ref>{{Citation |last1=Ye |first1=Huagu |title=Medicinal Ferns of Parkeriaceae, Athyriaceae, Thelypteridaceae, Aspleniaceae, Blechnaceae, Dryopteridaceae, and Davalliaceae |date=2021 |work=Common Chinese Materia Medica: Volume 1 |pages=93–125 |editor-last=Ye |editor-first=Huagu |url=https://link.springer.com/chapter/10.1007/978-981-16-2062-1_6 |access-date=2025-04-21 |place=Singapore |publisher=Springer Nature |language=en |doi=10.1007/978-981-16-2062-1_6 |isbn=978-981-16-2062-1 |last2=Li |first2=Chuyuan |last3=Ye |first3=Wencai |last4=Zeng |first4=Feiyan |last5=Liu |first5=Fangfang |last6=Wang |first6=Faguo |last7=Ye |first7=Yushi |last8=Fu |first8=Lin |last9=Li |first9=Jianrong |editor2-last=Li |editor2-first=Chuyuan |editor3-last=Ye |editor3-first=Wencai |editor4-last=Zeng |editor4-first=Feiyan|url-access=subscription }}</ref>
|As of 2021, systematic reviews of different medicinal applications showed no scientific consensus that they are effective in treating any conditions.<ref>{{Cite journal |last1=Flores-González |first1=Mathias |last2=Simirgiotis |first2=Mario |last3=Torres-Benítez |first3=Alfredo |date=2021-07-14 |title=Systematic Review: Antioxidant and Neuroprotective Capacity of Species of the Genus Asplenium (Monilophyta: Aspleniaceae) |url=https://www.mdpi.com/2673-9992/8/1/14 |journal=Plants |language=en |publisher=MDPI |pages=14 |doi=10.3390/IECBS2021-10665|doi-access=free }}</ref><ref>{{Cite journal |last1=Petkov |first1=Venelin |last2=Batsalova |first2=Tsvetelina |last3=Stoyanov |first3=Plamen |last4=Mladenova |first4=Tsvetelina |last5=Kolchakova |first5=Desislava |last6=Argirova |first6=Mariana |last7=Raycheva |first7=Tsvetanka |last8=Dzhambazov |first8=Balik |date=2021-05-25 |title=Selective Anticancer Properties, Proapoptotic and Antibacterial Potential of Three Asplenium Species |journal=Plants |language=en |volume=10 |issue=6 |pages=1053 |doi=10.3390/plants10061053 |doi-access=free |issn=2223-7747 |pmc=8225096 |pmid=34070269|bibcode=2021Plnts..10.1053P }}</ref>
|-
|[[Walnut]]s (Juglans)<ref name=":7" /><ref>{{Cite journal |last=Bennett |first=Bradley C. |date=2007-09-01 |title=Doctrine of Signatures: An explanation of medicinal plant discovery or Dissemination of knowledge? |url=https://link.springer.com/article/10.1663/0013-0001(2007)61%5B246:DOSAEO%5D2.0.CO;2 |journal=Economic Botany |language=en |volume=61 |issue=3 |pages=246–255 |doi=10.1663/0013-0001(2007)61[246:DOSAEO]2.0.CO;2 |issn=1874-9364|url-access=subscription }}</ref> [[File:Walnuts - whole and open with halved kernel.jpg|center|thumb|200x200px|Walnut nut and shell]]
|Believed to treat brain-related conditions because the seed resembles a brain or gastrointestinal complaints because of the appearance of the intestines.<ref name=":7" />
|Used to treat headaches.<ref>{{Cite journal |last=Marabini |first=Camilla |date=2024-12-10 |title=Food in Shakespeare: a Study of Culinary References in the Bard's Plays |url=https://unitesi.unive.it/handle/20.500.14247/15246 |journal=Ca'Foscari University of Venice}}</ref>
|Walnuts contain fatty acids, which are valuable for the brain.<ref>{{Cite journal |last1=Chauhan |first1=Abha |last2=Chauhan |first2=Ved |date=2020-02-20 |title=Beneficial Effects of Walnuts on Cognition and Brain Health |journal=Nutrients |language=en |volume=12 |issue=2 |pages=550 |doi=10.3390/nu12020550 |doi-access=free |issn=2072-6643 |pmc=7071526 |pmid=32093220}}</ref><ref>{{Cite book |last1=Mukherjee |first1=Soumya |url=https://www.taylorfrancis.com/books/9781003300502 |title=Plant-based Foods and their Implications in Brain Health |last2=Ramakrishna |first2=Akula |last3=Bhattacharjee |first3=Atanu |date=2024-11-19 |publisher=CRC Press |isbn=978-1-003-30050-2 |edition=1 |location=New York |language=en |doi=10.1201/9781003300502}}</ref> From a medicinal standpoint, there is not a significant evidence base that it can prevent cognitive decline.<ref>{{Cite journal |last1=Cahoon |first1=Danielle |last2=Shertukde |first2=Shruti P. |last3=Avendano |first3=Esther E. |last4=Tanprasertsuk |first4=Jirayu |last5=Scott |first5=Tammy M. |last6=Johnson |first6=Elizabeth J. |last7=Chung |first7=Mei |last8=Nirmala |first8=Nanguneri |date=2021-01-01 |title=Walnut intake, cognitive outcomes and risk factors: a systematic review and meta-analysis |journal=Annals of Medicine |volume=53 |issue=1 |pages=972–998 |doi=10.1080/07853890.2021.1925955 |issn=0785-3890 |pmc=8211141 |pmid=34132152}}</ref>
|}
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.<ref name=":03" /> Depending on the article, remedies connected to the doctrine vary in number and consistency.

== Scientific, spiritual, and social context ==
Signatures are often described as [[Post hoc ergo propter hoc|post hoc attributions]] and [[mnemonics]] used to remember the properties of a plant rather than the reason it was originally used.<ref name=":02">{{Cite journal |last=Bennett |first=Bradley C. |date=2007-09-01 |title=Doctrine of Signatures: An explanation of medicinal plant discovery or Dissemination of knowledge? |url=https://link.springer.com/article/10.1663/0013-0001(2007)61%5B246:DOSAEO%5D2.0.CO;2 |journal=Economic Botany |language=en |volume=61 |issue=3 |pages=246–255 |doi=10.1663/0013-0001(2007)61[246:DOSAEO]2.0.CO;2 |issn=1874-9364|url-access=subscription }}</ref> There is no scientific or historical evidence that plant shapes and colors have aided in the discovery of their medical uses.<ref name=":02" />

In Europe, the idea of doctrine of signatures was linked with Christian beliefs.<ref name=":02" /> However, similar theories were created within black magic with [[sympathetic magic]].<ref name=":12">{{Cite journal |last1=Dafni |first1=Amots |last2=Lev |first2=E. |date=2002-12-01 |title=The doctrine of signatures in present-day Israel |url=https://link.springer.com/article/10.1663/0013-0001(2002)056%5B0328:TDOSIP%5D2.0.CO;2 |journal=Economic Botany |language=en |volume=56 |issue=4 |pages=328–334 |doi=10.1663/0013-0001(2002)056[0328:TDOSIP]2.0.CO;2 |issn=1874-9364|url-access=subscription }}</ref> Similar theories have been observed all over the world in ancient Egypt, China, pre-Columbian America, and the Middle East.<ref name=":12" /><ref name=":02" /> This can also explain how varied, and at times contradictory, applications of the doctrine can be because traditional botany is subject to [[optimal foraging theory]].<ref name=":5">{{Cite journal |last1=Gaoue |first1=Orou G. |last2=Coe |first2=Michael A. |last3=Bond |first3=Matthew |last4=Hart |first4=Georgia |last5=Seyler |first5=Barnabas C. |last6=McMillen |first6=Heather |date=2017 |title=Theories and Major Hypotheses in Ethnobotany |url=https://www.jstor.org/stable/45171690 |journal=Economic Botany |volume=71 |issue=3 |pages=269–287 |doi=10.1007/s12231-017-9389-8 |jstor=45171690 |bibcode=2017EcBot..71..269G |issn=0013-0001|url-access=subscription }}</ref> Remedies would, in many cases, be based on the environmental availability of that resource rather than its objective effectiveness.<ref name=":5" />

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 it was a device used to elevate a group of "elite" observers who could interpret the world with more accuracy.<ref name=":10">{{Cite journal |last=Findlen |first=Paula |date=1995 |title=Review of Culture and Enchantment |url=https://www.jstor.org/stable/236481 |journal=Isis |volume=86 |issue=1 |pages=146–147 |doi=10.1086/357147 |jstor=236481 |issn=0021-1753|url-access=subscription }}</ref> In this context, the elite observers would be those that, for example, notice that lungwort's leaves look like lung tissue rather than positing that the dark red flowers could look like blood clots or the pink petals like irritated skin.<ref name=":10" /> The idea being that within many descriptors, the "correct" one that links to the signature could only be found by someone within this elite group.<ref name=":10" />

It is 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.<ref>{{Citation |last=Hankinson |first=R. J. |title=20 Galen on Hippocratic Physics |date=2016-01-01 |work=Ancient Concepts of the Hippocratic |volume=46 |pages=421–443 |url=https://brill.com/display/book/edcoll/9789004307407/B9789004307407_022.xml |access-date=2025-04-21 |publisher=Brill |language=en |doi=10.1163/9789004307407_022 |pmid=26731820 |isbn=978-90-04-30740-7|url-access=subscription }}</ref> Hypotheses like these and the questions they posed, regardless of the validity of the hypotheses themselves, inspired scientific investigations into the safety and usefulness of many plant-based remedies.<ref>{{Cite journal |last=Hill |first=Albert F. |date=1950 |title=Review of Drugs from Plants. Sigma Introduction to Science, 10 |url=https://www.jstor.org/stable/2811031 |journal=The Quarterly Review of Biology |volume=25 |issue=2 |pages=228 |doi=10.1086/397615 |jstor=2811031 |issn=0033-5770|url-access=subscription }}</ref><ref>{{Cite web |title=A World of Similarity: The Doctrine of Signatures and its application in medicinal plant identification |url=https://www.researchgate.net/publication/269688037 |archive-url=http://web.archive.org/web/20230201074900/https://www.researchgate.net/publication/269688037_A_World_of_Similarity_The_Doctrine_of_Signatures_and_its_application_in_medicinal_plant_identification |archive-date=2023-02-01 |access-date=2025-04-22 |website=ResearchGate |language=en}}</ref>

== In literature ==

The phrase "signatures of all things" appears in the beginning of episode three in James Joyce's novel ''[[Ulysses (novel)|Ulysses]]''. The character Stephen Dedalus is 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 ==
* [[Table of magical correspondences]]
* [[Sympathetic magic]]
* [[Naturalistic fallacy]]
* [[Pictogram]]

== References ==
'''Citations'''
{{Reflist|30em}}

'''Bibliography'''
{{refbegin}}
*{{cite book |last=Stern |first=Kingsley R. |title=Introductory Plant Biology |url=https://archive.org/details/introductoryplan00ster_0 |url-access=registration |edition=5th |year=1991 |publisher=Wm. C. Brown Publishers |isbn=0-697-09947-4 }}
*{{cite book |publisher=D. Appleton and Company |volume=2 |last=White |first=Andrew Dickson |title=A History of the Warfare of Science with Theology in Christendom |year=1896 |author-link=Andrew Dickson White |url=https://archive.org/details/cu31924022599330 }}
{{refend}}

== Further reading ==
* Boehme, Jakob (1651) ''Signatura Rerum'' (The Signature of All Things). Gyles Calvert.
:--- Translation by J. Ellistone.
* Buchanan, Scott Milross (1938) ''[https://books.google.com/books?id=93bOlHs9ZooC 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&nbsp;– 1800 AD''. Cambridge University Press.
* Porter, Roy (1997) ''The Greatest Benefit to Mankind: A Medical History of Humanity from Antiquity to the Present''. HarperCollins.

{{pseudoscience}}

[[Category:Obsolete medical theories]]
[[Category:Herbalism]]
[[Category:History of science]]
[[Category:Pseudoscience]]