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August 6, 2025 35 mins

16th-century Swiss physician Paracelsus was frustrated with established medical practice and academia and he was sometimes on the lam because of his beliefs. He wrote at length about the idea that items in the natural world carried “signatures” in their appearance that could tell you visually how they could be used medicinally.

Research:

  • Bennett, B.C. Doctrine of Signatures: An explanation of medicinal plant discovery or Dissemination of knowledge?. Econ Bot 61, 246–255 (2007). https://doi.org/10.1663/0013-0001(2007)61[246:DOSAEO]2.0.CO;2
  • Dafni, Amots, and E. Lev. “The Doctrine of Signatures in Present-Day Israel.” Economic Botany, vol. 56, no. 4, 2002, pp. 328–34. JSTOR, http://www.jstor.org/stable/4256605
  • “The Doctrine Of Signatures.” The British Medical Journal, vol. 1, no. 627, 1873, pp. 19–19. JSTOR, http://www.jstor.org/stable/25233757
  • “The Doctrine of Signatures.” John Moore Museum. May 11, 2021. https://www.johnmooremuseum.org/the-doctrine-of-signatures/
  • The Editors of Encyclopaedia Britannica. "laudanum". Encyclopedia Britannica, 19 Jul. 2025, https://www.britannica.com/science/laudanum
  • The Editors of Encyclopaedia Britannica. "Peasants’ War". Encyclopedia Britannica, 20 Aug. 2020, https://www.britannica.com/event/Peasants-War
  • Grzybowski, Andrzej and Katarzyna Pawlikowska-Łagód. “Some lesser-known facts on the early history of syphilis in Europe.” Clinics in Dermatology. Volume 42, Issue 2. 2024. Pages 128-133. https://doi.org/10.1016/j.clindermatol.2023.12.003.
  • Hargrave, John G. "Paracelsus". Encyclopedia Britannica, 3 Jul. 2025, https://www.britannica.com/biography/Paracelsus
  • “The history of syphilis part two: Treatments, cures and legislation.” Science Museum UK.  Nov. 8, 2023. https://www.sciencemuseum.org.uk/objects-and-stories/history-syphilis-part-two-treatments-cures-and-legislation
  • Kikuchihara, Y., Hirai, H. (2015). Signatura Rerum Theory. In: Sgarbi, M. (eds) Encyclopedia of Renaissance Philosophy. Springer, Cham. https://doi.org/10.1007/978-3-319-02848-4_405-1
  • Lund, F B. “PARACELSUS.” Annals of surgery vol. 94,4 (1931): 548-61. doi:10.1097/00000658-193110000-00009
  • Michaleas, Spyros N et al. “Theophrastus Bombastus Von Hohenheim (Paracelsus) (1493-1541): The eminent physician and pioneer of toxicology.” Toxicology reports vol. 8 411-414. 23 Feb. 2021, doi:10.1016/j.toxrep.2021.02.012
  • Paracelsus. “Of the supreme mysteries of nature. : Of the spirits of the planets. of occult philosophy. The magical, sympathetical, and antipathetical cure of wounds and diseases. The mysteries of the twelve signs of the zodiack.” London. 1656. Accessed online: https://archive.org/details/paracelsvsofsupr00para/page/n9/mode/2up
  • Simon, Matt. “Fantastically Wrong: The Strange History of Using Organ-Shaped Plants to Treat Disease.” Wired. July 16, 2014. https://www.wired.com/2014/07/fantastically-wrong-doctrine-of-signatures/
  • Tampa, M. et al. “Brief history of syphilis.” Journal of medicine and life vol. 7,1 (2014): 4-10.https://pmc.ncbi.nlm.nih.gov/articles/PMC3956094/#R6
  • Waite, Arthur Edward. “Lives of alchemystical philosophers based on materials collected in 1815 : and supplemented by recent researches with a philosophical demonstration of the true principles of the magnum opus, or great work of alchemical re-construction, and some account of the spiritual chemistry.” London. G. Redway. 1888. Accessed online: https://archive.org/details/livesofalchemyst1888wait

 

 

 

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Episode Transcript

Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:01):
Welcome to Stuff You Missed in History Class, a production
of iHeartRadio. Hello, and welcome to the podcast. I'm Holly
Frye and I'm Tracy V. Wilson. This is a topic
that actually came up on another show that I work
on occasionally called Our Skin. And here's the thing. I

(00:26):
was trying to do calendar math and it hurt my
heart in my brain because I can't figure out when
that one is coming out in relation to when this,
so we'll come out listen. I'm not the boss of
the schedule on that one, so I don't know what's
going on. But there's no overlap other than the mention
of the doctrine of signatures and a little bit of
talk about it. But it ended up being a thing

(00:48):
where I was like, you know, we should probably talk
about that because I don't know that we have and
there's some things and then this ended up being a
lot about Paracelsus because he is important in the history
of medicine. He's mentioned in a lot of our previous episodes.
There hasn't really been an episode focused on him, and

(01:09):
his life was super interesting. He was a very rebellious
person who was very frustrated with established medical practice and academia,
and he was sometimes on the lamb because of his beliefs,
which is pretty fun. I love that if you read
biographies of him, it's like and then he spent a
period of wandering, But then other accounts will be more
detailed and be like, oh, yeah, he got kicked out

(01:32):
and the one he was on the run and then
or not even in some cases, like we mentioned one
in this episode where he was actually wanted for a rest,
but in others it was just like everybody's real sicking
you paracels, you might want to get out of town.
But so I ended up very much down the rabbit
hole of him because he is one of the people

(01:54):
who really really set up this idea of signatures. He's
not the first to have the idea, but he really
expounded on it. He wrote a lot about it, and
so it makes sense to talk about him right alongside
the doctrine of signatures. So today we are going to
talk about his life and work, specifically as it related
to the doctrine of signatures. Before we humans understood the

(02:20):
science behind how the body functioned, which I mean that's
something we are still figuring out, but before we really
had the concept of things like evidence based medicine. There
was the doctrine of signatures, and that name makes it
sound like a book or a tract. Of course, there
have been books and tracks written about it, but that's
not anything physical. It's a concept. The idea is that

(02:43):
you can intuit the things from nature that might heal
a given medical problem by finding ways in which those
items from the natural world resembled the ailing part of
the body. So the signature of a plant in this
ideology is in its physical presentation. And as to where

(03:05):
all of this began, it's almost impossible to pinpoint. We'll
talk a little bit more about some theories later, but
for one, this concept of a plant's appearance giving a
clue as to its possible use kind of sprang up
in multiple world cultures over the centuries. And a second
problem in tracing the roots of this idea lies in
the fact that this was the type of information that

(03:28):
typically was passed down through oral tradition by people who
may have been considered healers in their communities, but not
necessarily doctors or any other profession that would have routinely
made notes about their work. There were occasional mentions of it.
Diascorides wrote in the first century CE quote the herb
Scorpius resembles the tale of the scorpion and is good

(03:51):
against his biting. That is a classic example of the
type of association that was being used to identify what
people believed might treat a problem in the Western world.
Sixteenth century physician Paracelsus is often invoked as perhaps not
the originator of this concept, but certainly a proponent of it,

(04:13):
and also as somebody who codified it. That, like the
terminology of signatures, kind of comes about or around his lifetime.
We'll kind of set the stage by talking about him
and his work. Paracelsus was born Philippus Ariolus Theophrastus Bombastis
von Honheim in Eimsen and Sweden in fourteen ninety three,

(04:38):
and as a boy he did go by the name Theophrastus.
His father, villem was a doctor and a chemist, and
his mother, Elsa Oschner, died when Theophrastus was still a
young child. He and his father moved to Austria, where
his father had gotten an appointment as the town physician
for Villac. There Theophrastus was educated in metal ma with

(05:00):
the intention that as he matured, he would work in
an administrative role in the mining industry of Villac, Austria.
So keep in mind this education, of course, would have
been a bit misguided. At the time, the idea of
transmutation of base metals into gold was still considered a
viable possibility, and people also believe that metals grew underground,

(05:22):
kind of like plants. But what the Ephrastus noticed was
that a lot of the people who worked in the
mines also had medical problems. The Ephrastus did not go
into the mining business, although that education would come into
play later. He went to the University of Vienna starting
in fifteen oh nine and studied math there as well

(05:43):
as astrology and medicine. After a year, which was considered
a completion of his coursework, he moved to the University
of Ferrara in Italy to get a medical degree. From
the age of fourteen, he knew he was called to
a life in medicine, and he chose the name Paracelsus
around fifteen sixteen, shortly after graduating. This offers an indication

(06:06):
that he intended to build on the work of Roman
physician Alice Cornelius Celsus, who lived in the first century
both BCE and CE. He also started kind of wandering
Europe in search of more knowledge, and this was not
entirely uncommon at the time. There had been an explosion
of universities in the Middle Ages, and the printing press

(06:29):
had been invented several decades earlier, and as a consequence,
this was a time when a lot of young thinkers
kind of chose to sample from multiple schools to gain
a broad knowledge base and also kind of seek a
place that felt right to maybe settle down and started life.
Theophrasis spent time at many universities throughout Germany, Austria, and Italy,

(06:50):
but he came away finding the educations that they offered
pretentious and unsatisfying. He famously wrote, I wonder how the
high colleges managed to so many high asses. Paracelsus also
found schools to be pretty useless for getting an education
for the medical vocation. He felt that a university setting

(07:13):
just didn't offer all the information that a doctor would
actually need in their day to day practice, so he
sought out other sources of information, and he came to
the conclusion that he could learn more from everyday people
who dealt with maladies as part of their lives than
he could from academics. He mentions in his writings speaking
with old wives, sorcerers, travelers, innkeepers, monks, barbers, alchemists, and

(07:41):
even gangs of bandits to learn what practices they found
to be beneficial. In fifteen twenty four, he returned to
Villac to visit his father before moving north to Salzburg.
That was where he planned to start practicing medicine, but
his plan in Salzburg got derailed by the German peasants.

(08:01):
This event could be its own episode, but for the
purposes of context for Paracelsus. In this uprising, peasants formed
armies to fight against the aristocracy, which was having its
own conflict with the Roman Catholic Church. But the moves
that the aristocracy was making for its own benefit were
only going to hurt the peasant class, and it would
actually push them from the status of vassals having some

(08:24):
ownership of the land to more of a debt bondage
serfdom position. And given what we said about Paracelsus already,
it's probably no surprise to anyone that he sided with
the peasants. But the peasants were really not equipped to
fight a war, and the aristocracy quickly defeated them, killing
and estimated one hundred thousand people in the process, although

(08:45):
some estimates put that number a good bit higher. And
Paracelsus survived this conflict, but because of his alliance to
the peasants, there was a warrant out for his arrest,
and so he fled Salzburg. This war came up in
our episode on Goods of the Iron Hand, which I
only remembered just now as we are sitting here, even

(09:08):
though that is an episode that I researched and wrote.
So if you want more about that, you can go
listen to the Goots of the Iron Hand episode. We'll
pick up more with Paracelsus's life after this uprising after
a sponsor break. After fleeing Salzburg, Paracelsis lived in Strasburg

(09:36):
for a while before moving on to Basel, Switzerland, and
in Basil he had several successes that would help to
establish his reputation as a doctor. First, he treated a
man named Johann Froben for an infection in his leg
that threatened that limb's future. It was believed before Paracelsus
got involved that the only real option was amputation, but

(09:58):
Paracelsis was able to so gave the leg by clearing
up that infection and helping it heal. It is not
entirely clear how he did this. Boy, am I curious though,
me too. I have a theory we can talk about
on behind the scenes. But it's not a treatment I
would wish on anybody, all right. His next case involved

(10:19):
a friend of Froben named Erasmus. Erasmus had an advanced
case of gout, and for this Paracelsus gave him laudanum.
Some people say Paracelsus actually invented laudanum, although his exact
recipe for it is unknown. It may differ from the
modern definition of what laudanum is, which is a tincture

(10:41):
composed of a ten percent solution of opium powder dissolved
in a high alcohol by volume spirit. Louddum is not
a cure for anything, although it is a very high
dose pain reliever, so high dosed that a part of
their symptoms include pain, especially, they might think they have

(11:02):
been cured, even though laudanum doesn't cure gout. Erasmus was
declared cured, and Paracelsus was soon given the job of
town doctor in Basle, and in that role he quickly
used his status to share his opinions on the medical
practice that had preceded him and just the medical establishment.

(11:22):
In June of fifteen twenty seven, he distributed handbills that
he was going to give a public speech, and when
that day came, Paracelsus appeared in a black robin hat
with red golden trim, carrying a staff and sword, and
he had an assistant with him who was carrying two
large books. So this particular day of this speech was

(11:43):
a day when Basil traditionally had a large public bonfire
as part of the celebration of the Feast of Saint John.
That fire was part of a university event that they
apparently had every year, and at this point Paracelsus taught
at the university. It fell under his duties as Basil
town physician. He sort of showboted for a moment before

(12:04):
the crowd, and then Paracelsus reportedly threw off his hat
and robe, broke his staff and threw the sword on
the ground, saying that a doctor should appear before patients,
not in fancy clothes and adornment, but with knowledge. Then
he threw one of the books on the fire, saying
that was Galen. A second book went on to the fire,

(12:26):
and he said that was Avicenna. We've talked about Avicenna
on the show also called Ibensina, back in twenty fourteen.
Paracelsus then continued this very scathing critique quote old bloodless words,
vain mouthings of ignorance, Latin sounds meaning nothing from these books.

(12:46):
Your doctors get their Latin for diseases they know nothing about,
and their Greek for diseases they never heard of. Gray
bearded frauds, old wormy, moth eaten sophists, lousy pretenders, with
their fire closed, their long steps, their Latin to hide
their ignorance. They cling to the rich like leeches and

(13:06):
let the poor die like flies. When there is a
real disease, they fly from it, afraid for their reputations.
Paracelsus also stated that the various cures that were frequently
used just caused more problems than the disease they were
meant to address, and that all of this was about
getting money, often from people who were being given false hope.

(13:31):
As you can imagine this presentation did not go over
well with any of his colleagues. He had at that
point publicly sought to discredit not only his employers, but
also his peers in academia. And while his push to
learn from and care from the common people of the
city seems very much like a feel good moment, it
was also deeply rooted in his own ego. So of

(13:54):
course he was correct to reject the belief put forth
by Galen that the body was composed of for us
and that an imbalance in those humors was the source
of disease. Like he was rejecting things that were not
founded in science. Uh, And he was extolling the virtues
of looking to nature and the common people for cures.
But he was also pretty clear that he understood all

(14:16):
of that way better than anyone else possibly could. Yeah,
this is like such a similar attitude to like the
wellness industry today saying established doctors know nothing, we have
all the answers. Uh huh. Like this was the same,
the same thing kind of playing out centuries ago. Additionally,

(14:41):
this meant that he considered things like fairies to be real,
and that different varieties of those fairies corresponded to the
elements of earth, water, air, and fire, those being respectively, gnomes, undines, sylphs,
and salamanders. He explained that these elementals were soulless spirits
that were living in the matrices of each element, and

(15:04):
he wrote a lot about these entities and their lifestyles.
He wrote so much, and I was reviewing so much
that I was like having a hard time picking what
I wanted to share. But this tickled me, So here
we go of nomes, he wrote, quote, the lot of
man is very hard. To hope or to wish will
profit him nothing, and he must work for all he wants.

(15:27):
But the nomes have whatever they seek without any labor
in getting or preparing it. Concerning their day and night,
they're sleeping and waking hours, the case is exactly the
same with them as with men. Moreover, they have a
sun and a firmament, no less than we have. That is,
the gnomes have the earth, which is their chaos. This
is to them only as our atmosphere. It is not

(15:49):
as earth to them in our sense. Hence, it follows
that they see through the earth just as we do
through the air, and the sun shines for them through
the earth as it does for us through the air,
for they have the sun, the moon, and the whole
firmament before their eyes. So the four humors are bad,
but y'all gnomes are real, and we need no mention.

(16:12):
Four humors are bad, but four types of fairies are good.
This whole idea of four earthly elements was grounded in alchemy.
That was something that as a boy he had studied
with his father and with other teachers. He also thought
that ghosts were real, explaining them as sort of echoes
of a human trapped on the earthly realm for a

(16:34):
while after death. I feel like this is still a
common way that people talk about ghosts. He was groundbreaking
for his time, but also working with some really non
scientific ideas by modern standards. He also advocated that many
of the spirits that the church had characterized as bad
were just these elementals, and they were scientific, and this too,

(16:56):
ruffled a lot of feathers in academic circles. He seems
to have been really at odds with just about everybody
in the town who could have been considered a professional colleague.
So cut to fifteen twenty eight, by which point it
was pretty clear that it was time for Paracelsus to
leave Basel. He did not settle down for several years,

(17:18):
and he kept moving around, in part because people would
get real tired of him. But he was also returning
to the habit of his earlier years, where he kind
of traveled and studied, although at this time he was
not stopping in for study at universities. He instead observed
real people and their medical issues, and he also, it

(17:39):
seems worked as or shadowed a field medic for the
Venetian Army, and all of this falls in line with
his frequently quoted line of writing, a doctor must be
a traveler. Knowledge is experience. During these years he wrote
about a treatment for syphilis, as well as his theory
on the origin of syphilis. We know what causes syphilis today,

(18:03):
but its exact origins on Earth are still not known.
He believed that this had originated as a result of
sexual intercourse between a sex worker who had gonorrhea and
a person with leprosy. This belief in the origin of
syphilis probably explains his proposal to treat syphilis with mercury,

(18:24):
which was also being used to treat leprosy. Paracelsus wrote
about this treatment in fifteen thirty and it was used
for centuries. This is probably because it did appear in
some cases to eliminate the disease, but modern medical experts
and historians suspect that this was actually the result of
observing syphilis going into a dormant period, which is something

(18:48):
that it naturally does. And there were certainly patients who died.
Their deaths were chalked up to the disease, but it's
just as likely that they died of mercury poisoning. In
his traveling years, Paracelsus also wrote what would become probably
his most well known work. This was Der grozen Wundertzne.

(19:10):
It's a great surgery book. I probably butchered that German
that was published in fifteen thirty six, and this was
based on his time working with military units and treating wounds,
as well as observing how soldiers manage their own care.
And then we get to his writings on hermetic chemistry.
Hermeticism references the writings of a man the Greeks called

(19:32):
Hermes Trismagistos, the Egyptian god Toth. Those writings examine astrology,
the occult, theology, and philosophy, and there's a whole section
of Paracelsus's Hermetic Chemistry writings called concerning the Signature of
Natural Things. So this writing is not only about medicine.

(19:53):
It talks about what the signature of things is. Paracelsus
explained that in his there are only three signators, Man, Archaos,
and the stars, and Archaeus is a term that he
used to describe the vital principle that's responsible for the
growth and continuation of all living things. So, in a

(20:13):
very boiled down sense, that's what he's calling the natural world.
And there's a lot of talk in this writing about
the ways that people can choose to signify themselves, i e.
How they present publicly through dress and presentation, and all
of this really is him setting up this idea that
you can tell a lot about a person or a
thing by simply looking at it. This is a problem.

(20:37):
As an example, quote, black eyes not only denote a
healthy constitution, but also, for the most part, a constant mind,
free from doubt and fear, healthy and hearty, truthful and
loving virtue. Gray eyes are the sign of a crafty man,
Ambiguous and inconsistent. Weak eyes denote good counsels, clever and
profound deliberations and so on. Bright eyes, which turn up

(21:02):
down into both sides, denote a false clever man who
cannot be deceived, faithless, shirking work, desirous of ease, seeking
to gain his livelihood, and laziness by gambling, usury, impurity, theft,
and the like. Obviously this is nonsensical, and there are
many other ways in which Paracelsus believed that a person's

(21:25):
appearance could tell you about their personality and behavior. He
also wrote at length about chiromancy or palm reading, as
though it were a hard science, and the planets and
the metals that they were associated with, and even necromancy,
and then he gets to the curatives. One, for example,
is a tincture made from urine, and there's a full

(21:48):
recipe quote. Take old urine poured away from its deposits,
several cops of it, in which dissolve three handfuls of
ground salt. When you have strained it, boil it and
skim it carefully. In this again, dissolve a handful of
bruised vitriol that's sulfuric acid with two or three ounces

(22:08):
of bruised salt ammoniac, and then carefully skim again with
this liquid, imbibes some filings, and boil it until it
can be pulverized. The dust thus produced reverberate over a
powerful fire, continually stirring it with an iron rod, until
it changes from its own color to another, and at

(22:28):
last to the hues of most brilliant violet. From this
you can easily, with spirits of wine or distilled acetum,
draw off the tincture, and when it is extracted by
separation of the elements, you will collect what remains at
the bottom of the glass. By means whereof you will
be able to produce wondrous effects both within and without

(22:49):
the body. Throughout his various writings on what he calls signatures,
Paracelsus explains that the Earth purposely makes plants resemble other
things to that humans can see the correct plant to
treat their illnesses, but that they don't even necessarily need
to see those things, because our intuition already knows this

(23:10):
truth without consciously seeing the signature. He wrote, quote, the
soul does not perceive the external or internal physical construction
of herbs and roots, but it intuitively perceives at once
their signatum. His idea gleaned from speaking with everyday people,
and which was expounded upon by scientists that followed. Was

(23:31):
it like if you find a plant with a kidney
shaped leaf, that it would be useful in treating ailments
of the kidneys. We should note, though, that this line
of treatment, as outlined by Paracelsus is often a bit
more indirect than simply consuming a plant that you see.
Because he loved his lab work, sometimes he worked things
into a tincture, such as that long process with urine

(23:54):
that we just described. He treated plague in a similar way,
using my minute amounts of the patient's excrement and preparing
a medicine for them. Allegedly he cured a number of
people this way. Yeah, I would like to see the
notes on that. Paracelsus's end is actually a little bit

(24:15):
of a mystery. We know that he died in Salzburg, Germany,
on September twenty fourth, fifteen forty one, at the age
of forty eight, but exactly how that happened has been
relayed in consistently in various accounts through the years. However
it happened, it does appear that it was relatively sudden,
so in one account he is said to have died

(24:35):
in the kitchen of an inn that he was staying at.
Sometimes references that he was sitting on a bench near
the stove and just passed away. Another also mentions the inn,
which is the White Horse Inn, and that account says
he died in his bed there after a sudden illness
that came on that he had for a few days.
And then there is another version that can kind of

(24:57):
build on these two scenarios suggest that the suddenness of
his death or illness was because he had perhaps been
poisoned by an assassin hired by a fellow physician, or
group of physicians who did not like Paracelsus's shakeup of
their profession. We will talk about the doctrine of signatures
after Paracelsus in just a moment, but first we'll hear

(25:21):
from the sponsors that keep the show going. Paracelsus's death
was hardly the end of his work. His writings on
signatures had a life of their own. And also he
did not call it the doctrine of signatures. It picked

(25:42):
up that name several decades later when other people were
writing about it. But the other thing is he had
written additional texts that got published posthumously, and his combination
of science and the occult has remained alluring for a
great many readers in the century since he died. Even
people today, I find them alluuring because they're interesting, but

(26:05):
I don't think they're science. Keep in mind too, that
this time of Paracelsus's life was really a big moment
in human history, particularly in Europe. So at the same
time that Theophrastus slash Paracelsus was exploring the world of knowledge,
the earliest voyages of Spain to North America were underway,

(26:26):
and the beginning of colonization by Europeans. Da Vinci was
painting his masterpieces, Michelangelo was just starting his career, and
Martin Luther was about to start a big uproar in
challenging the Catholic Church. Paracelsus was sometimes called the Luther
of doctors, and he hated it because he was like,
everybody hates him and wants to kill him. Please don't

(26:47):
say that about me. So it is important as we
talk about this to contextualize the work of Paracelsus in
a world that was undergoing a lot of other massive changes.
We know that he was not the only person who
believed in this idea of the doctrine of signatures. But
as we mentioned earlier, the origin of this concept is unknown.

(27:11):
There are a number of ideas related to Paracelsus's use
of the writings of Hermes Trismagestus. There's one school of
thought that the doctrine of signatures originated in Egypt. There's
also a theory that China is really where these concepts began,
and that as trade routes were established with Europe in
the Middle Ages, these ideas spread quickly. There's a whole

(27:34):
other approach that takes the position that we as humans
just want to apply some sort of pattern recognition to
the world around us in order to understand it, regardless
of where we come from geographically or culturally. We're going
to talk about that reference to Chinese origins again in
just a minute. But in the West, all of this

(27:56):
kind of got rolled up under a religious ideology suggesting that,
of course God created all of these clues in the
way things in the natural world were shaped to lead
us to the right treatments. But there are of course
problems inherent in that. For one, it hinges on the
idea that everyone believes in the same god. Doesn't account
for religions where there would be multiple gods. Who's responsible

(28:18):
for making plants shape like organs? For another, It also
puts humankind at the center of everything in the universe,
as though all of these things were created just for us.
Putting all of that aside, what if two physicians were
to disagree on what signature a plant had. That was
part of the early criticism of the doctrine of signatures,

(28:40):
which started really almost as soon as Paracelsus had started
writing his long explanations of it. Flemish physician and botanist
Ramberda Donce, sometimes called the father of botany, wrote of
the doctrine just a couple of decades after Paracelsus's passing,
saying quote, it is so changeable and uncertain that it

(29:01):
seems absolutely unworthy of acceptance. Others followed suit over the years,
including the father of homeopathy, Samuel Hahnemann. The doctrine of
signatures persisted, though, as a guiding tool for medicine, for
a long time. This excerpt is from the British Medical
Journal in eighteen seventy three, and it denounces it is backward,

(29:23):
but the ongoing fascination with it is apparent quote. According
to M. Googler's recent report to the Academy of Medicine
in Paris on the Chinese Materia medica, the belief in
the specific action of drugs seems to have strongly influenced
medical practice in China as it did but lately that
of Europe. Besides, the Chinese believe, as the Europeans did

(29:45):
in the Middle Ages, that the appearance of a substance
will give a clue to the services it may render
to man i e. The doctrine of signatures. Thus, the
luciole is recommended for affections of the visual organs. A
matter having a red root is given for a mental
Polygonum tinctorium, which yields indigo, is reputed efficacious for eruptive fevers.

(30:07):
The reniform fruit of the kadsurachenensis is said to possess
aphrodisiac properties, while ginseng, with its bifurcated root resembling the
legs of a man, is looked upon as restoring virile
powers to the sick and aged. Considerations of the same
kind are doubtless the foundations of the reputation of the
Cordyceps senensis as exciting the genital organs, that of the

(30:30):
Bardon's parvaflora as infallible in making the nails grow. These
are strange illusions, but they merit indulgence from those whose
ancestors administered the lungwort to cure thesis, the gromwild to
cure the gravel, and the carrot for the jaundice. As
more rigorous methods of testing substances and recording treatment efficacy evolved,

(30:51):
the doctritive signatures fell out of favor because so many
of the claims that had been made by its followers
were really proven false. For the most part, the doctrine
of signatures is seen today as a misguided or backwards thinking,
even if it was cutting edge science of the sixteenth century.
But then there are instances where some of the associations

(31:13):
made through it have turned out to actually be useful.
Is there a way to reconcile that some people think so?
In a two thousand and seven article in Economic Botany,
Bradley Bennett suggests a possible reinterpretation of the doctrine of signatures,
writing quote, in traditional cultures, plant knowledge is effectively passed

(31:37):
from one generation to the next through observation and oral tradition.
The doctor of signatures should be reevaluated with respect to
one its role in the discovery of medicinal plants, two
post hawk attribution of signatures, three the nature of signatures,
and four its role as a mnemonic. So this idea

(31:57):
is that a plant that was found to have a
benefit then could have the association of characteristics related to
the illness it was treating applied to the plant retroactively
to sort of help people remember, Oh, that's the plant
that helps me with this thing. Bennett continues later in
that write up, quote, a signature like beauty is in

(32:19):
the eye of the beholder. In sixteen twenty eight, Gui
de le Bross noted that it was easy to imagine
any resemblance between a plant and an animal that happened
to be convenient. Bennett also notes later in that same
paper that quote, seeing a particular signature often requires a
vivid imagination. As a PostScript, we really haven't included a

(32:42):
lot in the way of examples in this episode of
plants that look like a human organ, and then people
might use it to treat an illness related to that organ.
That's on purpose, because there are still people who want
to apply this method. When I was in massage school,
I had an herbal medicine teacher who brought them up repeatedly.

(33:04):
We are not gonna feed into that. Yeah. I also
in an age when things get scrubbed and reported to
people as though it's real, threw AI out of context.
We're not going to offer anything that might help that, right,
because I don't want anybody to get hurt. So that
is the doctorate of signatures and Paracelsus for today. I

(33:28):
have sewing email which makes me great in my heart.
This email is from Sarah and it makes me so
happy and it involves one of the cutest dogs in
the world. Sarah writes, I am in my seventies. I
started sewing when I was probably eleven. Sewed lots of
clothes for myself as a teenager, including a pantsuit alongside
my best friend, sewing hers. We wore them to see

(33:51):
the monkeys at the Hollywood Bowl, just in case we
might meet them. I sewed my wedding dress and lots
of clothes for my kids. I loved the folk patterns
at that time. That was a brand. By the way,
when my creative daughter showed interest in sewing. She issued patterns.
She created all kinds of interesting things, including complex wallets
and purses, just making them up for herself. So fast

(34:14):
forward to the present. I was so excited to hear
your shows on sewing patterns. They were fascinating. And then
a couple of days later, my daughter, her wife and
I started watching The Great British Sewing Bee and guess
what they talked about in the first episode, sewing pattern history.
I was yelping with delight repeatedly while watching the segment.
So fun when worlds collide like that and make sparkles.

(34:35):
Thank you for a fascinating topic well covered. This is Luna,
our rescue from taiwan dog. She is a Taiwanese Mountain
dog cross and the sweetest dog ever. She adores her
family and worries until we all six of us in
the house are back home. This dog is so cute.
It's a sweet little black pup and she has white
sprinkles on her paws and oh, she's really really cute,

(34:58):
and she's hugging a lamb me and it's really adorable.
And then there's Bonus Kitty. This is Mercury one of
our three Humane Society kitties. He is pretty wild and
so much fun. He's also beautiful. This also worked out
because Mercury came up in the episode, and I'm gonna
talk about it in behind the Scenes on Friday. Okay,
we are so thankful Sarah for you sharing this. I'm

(35:19):
glad you like the sewing patterns episode. I always worry
when it's very much in my super Nietzschee interests. But
it might not be for everyone, but I'm glad it's
for some people. If you would like to write to us,
you can do so at History Podcasts at iHeartRadio dot com.
You can also subscribe to the show on the iHeartRadio
app or wherever you listen to your favorite shows. Stuff

(35:42):
you Missed in History Class is a production of iHeartRadio.
For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts,
or wherever you listen to your favorite shows.

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