Paracelsus (said to be pronounced /ˌpærəˈsɛlzəs/; German: [paʁaˈtsɛlzʊs]; born 10 November 1493, died 24 September 1541), whose full name was Philippus Aureolus Theophrastus Bombastus von Hohenheim, was a Swiss doctor, alchemist, religious scholar, and thinker during the German Renaissance.
He helped change medicine during the Renaissance by focusing on observing patients and combining that with traditional knowledge. He is known as the "father of toxicology" because he studied how poisons affect the body. Paracelsus also made predictions about the future, and his writings were studied by a group called the Rosicrucians in the 1600s. A medical movement called Paracelsianism developed later, based on the ideas found in his works.
Biography
Paracelsus was born in Einsiedeln, a village near the Etzel Pass in Schwyz. He was born in a house next to a bridge over the Sihl River. His father, Wilhelm (died 1534), was a chemist and physician. Wilhelm was not born to married parents and was a descendant of the noble Georg [de] Bombast von Hohenheim (1453–1499), who was a commander of the Order of Saint John in Rohrdorf.
Paracelsus’s mother was likely from the Einsiedeln region and worked as a bondswoman for Einsiedeln Abbey before her marriage. She also served as a superintendent in the abbey’s hospital. Paracelsus often wrote about his rural background and sometimes used the name Eremita (“hermit,” from the name of Einsiedeln, meaning “hermitage”) in his writings.
Paracelsus’s mother likely died in 1502. After her death, his father moved to Villach, Carinthia, where he worked as a physician, treating pilgrims and people in a cloister. Paracelsus was educated by his father in botany, medicine, mineralogy, mining, and natural philosophy. He also received a strong humanistic and theological education from local clergy and the convent school of St. Paul’s Abbey in Lavanttal. It is likely that his father taught him most of what he learned early in life. Some biographers say he studied with four bishops and Johannes Trithemius, abbot of Sponheim. However, there is no evidence that Trithemius spent much time in Einsiedeln or that Paracelsus visited Sponheim or Würzburg before Trithemius’s death in 1516. It is more likely that Paracelsus learned from their writings, not from direct teaching. At age 16, he began studying medicine at the University of Basel and later moved to Vienna. He earned his medical doctorate from the University of Ferrara in 1515 or 1516.
Paracelsus sought knowledge that was not found in books or traditional teachings. Between 1517 and 1524, he traveled widely across Europe, visiting Italy, France, Spain, Portugal, England, Germany, Scandinavia, Poland, Russia, Hungary, Croatia, Rhodes, Constantinople, and possibly Egypt. During this time, he worked as an army surgeon and participated in wars led by Venice, Holland, Denmark, and the Tatars. After returning home, he tried to settle in Salzburg, Austria, but fled to avoid arrest for his involvement in the Peasants’ Revolt. Later, he became a citizen of Strasbourg.
In 1524, after visiting his father in Villach and finding no local work, Paracelsus settled in Salzburg as a physician and stayed there until 1527. From 1519 or 1520, he had been writing medical works and completed Elf Traktat and Volumen medicinae Paramirum, which described eleven common illnesses and early medical ideas. While returning to Villach and working on these writings, he considered deep questions about life, death, health, disease causes, humanity’s place in the world, and the relationship between humans and God.
In 1526, Paracelsus bought citizenship in Strasbourg to practice medicine. Soon after, he was called to Basel to treat Johann Frobenius, a printer, and reportedly cured him. At the same time, Erasmus of Rotterdam, a Dutch Renaissance humanist at the University of Basel, observed Paracelsus’s skills and exchanged letters with him about medicine and theology.
In 1527, Paracelsus became a city physician (Stadtarzt) in Basel and was allowed to lecture at the University of Basel. Basel was a center of Renaissance humanism, and Paracelsus met Erasmus, Wolfgang Lachner, and Johannes Oekolampad. When Erasmus fell ill in Basel, he wrote to Paracelsus: “I cannot offer you a reward equal to your art and knowledge—but I offer you a grateful soul. You brought Frobenius back from the dead, who is my other half. If you save me, you will save both of us.”
Paracelsus’s lectures at the University of Basel were given in German, not Latin. He wanted his lessons to be accessible to everyone. He criticized Basel’s physicians and apothecaries harshly, causing political unrest and threats to his life. To show his rejection of traditional medicine, he publicly burned books by Galen and Avicenna. On June 23, 1527, he burned a copy of Avicenna’s Canon of Medicine, a major academic text, in the market square. He often used strong language, disliked untested theories, and mocked people who valued titles more than practical skills. He said, “If disease tests us, all our splendor, titles, rings, and names will be as helpful as a horse’s tail.” During his time as a professor, he invited barber-surgeons, alchemists, and apothecaries—people without formal education—to demonstrate his belief that only those who practiced an art truly understood it: “The patients are your textbook, the sickbed is your study.” Paracelsus was compared to Martin Luther because of his defiance of medical authorities, but he refused the comparison, saying, “I leave it to Luther to defend what he says, and I will be responsible for what I say. If you wish Luther in the fire, you wish me in the fire too.” A companion from his time in Basel described him as someone who spent much time drinking and eating, rarely being sober. Threatened with a lawsuit, he left Basel for Alsace in February 1528.
In Alsace, Paracelsus returned to being an itinerant physician. After staying in Colmar with Lorenz Fries and briefly in Esslingen, he moved to Nuremberg in 1529. His reputation preceded him, and local medical professionals refused to let him practice.
The name “Paracelsus” first appeared in 1528 as a pseudonym for a political-astrological work published in Nuremberg. Pagel (1982) suggests the name was used for non-medical works, while his real name, Theophrastus von Hohenheim, was used for medical writings. The first use of “Doctor Paracelsus” in a medical publication was in 1536, as the author of Grosse Wundartznei. The name is usually interpreted as a Latinized version of Hohenheim (based on “Celsus,” meaning “high” or “tall”) or as a claim to “surpass Celsus.” Some believe the name was given to him by friends in Colmar in 1528, not by Paracelsus himself, who opposed Latinized names.
Philosophy
Paracelsus was a doctor who lived in the early 16th century. He was influenced by ancient philosophical ideas that were important during the Renaissance, such as those taught by Marsilio Ficino and Pico della Mirandola. Astrology played a key role in his medical practice, and he used it to help treat illnesses. Many doctors of that time also studied and used astrology. Paracelsus wrote about how to make special objects called talismans, which were believed to help cure diseases.
Paracelsus believed that science and religion were closely connected. He thought that discoveries in science were messages from God, and it was a sacred responsibility for people to learn and understand these messages. He believed that the qualities found in natural things, like plants or minerals, were not natural but supernatural. These qualities existed in God before the universe was created and would return to God when the Earth and the heavens no longer existed. This idea is similar to a belief from Aristotle about where elements belong in nature. Paracelsus saw science as a way to learn about the world and also to find signs of God’s presence. He believed that someone who did not believe in God could not be a successful doctor, because they would not be working in God’s name. To Paracelsus, being a good doctor required faith in God, strong character, and devotion to spiritual values. He encouraged doctors to study philosophy, improve themselves, and practice humility, believing these traits were as important as medical skills.
Chemistry and alchemy
Paracelsus was one of the first medical professors to recognize that doctors needed strong knowledge in natural sciences, especially chemistry. He was the first to use chemicals and minerals in medicine.
Paracelsus was likely the first to name the element zinc (zincum) around 1526. He may have chosen the name because the crystals of zinc looked sharp and pointed after being heated. In German, "zink" means "pointed." Paracelsus also created chemical therapy, chemical tests for urine, and suggested a theory about how digestion works using chemistry. He used chemistry in his teaching to medical students and doctors, but many people disagreed with his ideas.
In the early 1500s, Paracelsus unknowingly observed hydrogen. He noticed that when acids react with metals, a gas forms as a byproduct. Later, in 1650, Théodore de Mayerne repeated this experiment and found the gas was flammable. However, neither Paracelsus nor Mayerne thought the gas was a new element.
Paracelsus rejected the ideas of Aristotle and Galen, as well as the theory of humors. He accepted the four classical elements—water, air, fire, and earth—but saw them as a base for other properties. In a book published after his death, A Book on Nymphs, Sylphs, Pygmies, and Salamanders, and on the Other Spirits, he described four elemental beings. Salamanders were linked to fire, gnomes to earth, undines to water, and sylphs to air.
Paracelsus often described fire as the "Firmament," a layer between air and water in the sky. He used an egg to explain the elements. He said air surrounded the world like an eggshell. The egg white below the shell was like fire because it had a chaotic quality that supported earth and water. Earth and water formed a globe, like the yolk of an egg. In De Meteoris, Paracelsus said the firmament was the heavens.
From his study of elements, Paracelsus used the idea of three main parts to explain medicine. He believed medicines were made of three principles: sulphur (a flammable part), mercury (a fluid and changeable part), and salt (a solid, lasting part). He first wrote about this "three primes" theory in a work called Opus paramirum around 1530. Paracelsus thought that sulphur, mercury, and salt were the causes of diseases. He believed each disease had three possible cures, depending on which principle was affected. He took these ideas from medieval alchemy, where sulphur, mercury, and salt were important. He demonstrated his theory by burning wood, saying fire was sulphur, smoke was mercury, and ash was salt. Paracelsus also believed these three principles explained the nature of medicine and human identity. Salt represented the body, mercury the spirit (like imagination and judgment), and sulphur the soul (like emotions). He thought understanding these principles helped doctors treat diseases. He also believed that substances harmful in large amounts could help in small amounts, using examples like magnets and static electricity.
Although Paracelsus accepted the four classical elements, Robert Boyle criticized his ideas in The Sceptical Chymist (1661). Boyle wrote that Paracelsus’ three principles (sulphur, mercury, and salt) were not as well-supported as Aristotle’s theory of the four elements. Boyle argued that Paracelsus’ ideas were based on limited experiments and were less reliable than Aristotle’s theory, which had been studied for centuries. Boyle also rejected both Paracelsus’ three principles and the classical elements, saying no system should assume a fixed number of elements. He focused his criticism mainly on Paracelsus’ theory, arguing that if it had flaws, so did Aristotle’s theory.
Contributions to medicine
Paracelsus believed that health and sickness in the body depended on the balance between humans (microcosm) and nature (macrocosm). He used a different method than earlier doctors, focusing not on purifying the soul but on finding the right balance of minerals in the body. He thought certain illnesses could be cured with chemical treatments. Because of this belief, he saw the universe (macrocosm) reflected in every person (microcosm). One example of this idea is the doctrine of signatures, which used the appearance of plants to guess their healing powers. For instance, the root of the orchid resembled a testicle, so it was thought to help treat illnesses of that body part. Paracelsus used the microcosm-macrocosm theory to show how the goals of health and salvation were connected. Just as people needed morality to protect themselves from evil spirits, they also needed good health to avoid disease.
Paracelsus believed that true understanding of the body required knowing what each part needed to stay healthy. He thought the stars influenced body parts and that diseases came from "poisons" sent from the stars. However, he did not see these poisons as always harmful, because their effects depended on the amount used. Unlike Galen, Paracelsus believed that similar substances could cure similar illnesses. He argued that because everything in the universe was connected, healing ingredients could be found in herbs, minerals, and chemical mixtures. Paracelsus saw the universe as a single living system filled with a life-giving spirit, including humans, which he called "God." His ideas clashed with the Catholic Church, which believed the creator and created were separate. Because of this, some people thought of him as a Protestant.
Paracelsus is often credited with bringing opium back to Western Europe during the German Renaissance. He praised the benefits of opium and a medicine he called laudanum, which was later believed to be an opium tincture. However, he did not leave a complete recipe, and the ingredients he used were different from those in 17th-century laudanum.
He also created or named a liniment called opodeldoc, a mixture of soap in alcohol, with camphor and sometimes herbal essences like wormwood added. His recipe became the basis for later versions of this medicine.
His work Die große Wundarzney was an early step toward antisepsis, a practice of keeping wounds clean to prevent infection. This idea came from his experiences as a military doctor during the Venetian wars. He argued that using dirty substances like cow dung or feathers on wounds should stop, and instead, wounds should be kept clean. He believed that if infection was prevented, the body could heal on its own. At the time, many doctors thought infection was a natural part of healing, but Paracelsus promoted cleanliness, wound protection, and proper diet. He was also the first to recognize that syphilis was an inherited disease and that it spread through contact. He treated it with carefully measured doses of mercury.
Hippocrates believed illness came from an imbalance of four humors: blood, phlegm, black bile, and yellow bile. Galen later expanded this idea, which remained popular until the mid-1800s. Paracelsus, however, believed in three humors: salt (stability), sulfur (combustibility), and mercury (liquidity). He saw disease as the separation of one humor from the others. He thought body organs worked like alchemical tools, separating pure from impure. At his time, common treatments included diets, purging, and bloodletting to balance the four humors. Paracelsus disagreed, arguing that illness came from outside agents, not internal imbalances. He opposed excessive bloodletting, saying it disrupted the body’s harmony. He believed fasting helped the body heal itself, calling it "the greatest remedy, the physician within."
Paracelsus introduced clinical diagnosis and specific medicines, which was unusual for his time, when many relied on general cures. He suggested that diseases were separate entities, not just states of being, an idea that foreshadowed the germ theory. He used black hellebore for arteriosclerosis and recommended iron for "poor blood." He is also credited with creating the terms "chemistry," "gas," and "alcohol."
During his lifetime and after, Paracelsus was seen as a miracle healer who studied folk medicines ignored by traditional doctors like Galen and Avicenna. Some believed he cured the plague with his remedies. Before the 19th century, effective treatments for infectious diseases were unknown, so he developed many of his own. For fevers, he prescribed diaphoretics and tonics for temporary relief. His remedies often included "theriac," a medicine from Eastern traditions sometimes containing opium. One of his recipes for a potion to treat plague was:
"Make the potion so that the plague is expelled through sweat: one measure of medicinal brandy, twelve parts of theriac, four parts of myrrh, six parts of horse chestnut root, one part of whale sperm, one part of medicinal earth, two parts of swallow root, one part each of diptan, bibernel, and valerian root, and a quarter part of camphor. Mix all together in a clean glass, let it sit in the sun for eight days, then give the sick person half a spoonful."
— E. Kaiser, Paracelsus. 10. Auflage. Rowohlt's Monographien. p. 115, Reinbek bei Hamburg. 1090- ISBN 3-499-50149-X (1993)
One of his less-known achievements was studying minerals and the healing power of alpine mineral springs. His travels took him to many remote areas, where he gathered knowledge about natural remedies.
Reception and legacy
The oldest known portrait of Paracelsus is a woodcut created by Augustin Hirschvogel in 1538. This image was made while Paracelsus was still alive. An earlier painting by Quentin Matsys was lost, but three 17th-century copies remain. One was painted by an unknown Flemish artist and is stored in the Louvre museum. Another was painted by Peter Paul Rubens and is in Brussels. A third was painted by a student of Rubens and is now in Uppsala. A second portrait by Hirschvogel, dated 1540, claims to show Paracelsus at the age of 47, less than a year before his death. In this portrait, Paracelsus is shown holding his sword with his right hand, gripping the spherical pommel. The image includes two mottos: "Let no man belong to another who can belong to himself" and "All perfect gifts are from God, imperfect ones from the Devil." Later portraits include a German version of these mottos in rhyming lines. Portraits made after Paracelsus’s death, especially in the second half of the 16th century, often show him in the same pose, holding his sword by its pommel.
A portrait known as the "Rosicrucian portrait," published in 1567 with a book titled Philosophiae magnae Paracelsi, is based on the 1540 Hirschvogel portrait but mirrored, so Paracelsus’s left hand rests on the sword pommel. This image includes additional details: the sword’s pommel is marked with the word "Azoth," and the Bombast von Hohenheim family crest appears next to Paracelsus, surrounded by eight crosses. In the background, symbols linked to early Rosicrucian beliefs are shown, including a child’s head emerging from the ground, representing rebirth. This portrait may have been created by Frans Hogenberg under the guidance of Theodor Birckmann.
German Rosicrucians highly respected Paracelsus, seeing him as a prophet. They studied his writings systematically, a field sometimes called "Paracelsianism." Francis Bacon warned against Paracelsus and the Rosicrucians, stating that Paracelsus and alchemists had distorted the idea that humans are "microcosmus" (small representations of the universe).
Paracelsianism also led to the first complete collection of Paracelsus’s works. Johannes Huser of Basel gathered original writings and manuscripts, creating a ten-volume edition between 1589 and 1591.
Prophecies in Paracelsus’s writings on astrology and divination were published separately as Prognosticon Theophrasti Paracelsi in the early 17th century. His prediction of a "great calamity just beginning," linked to the End Times, was later associated with the Thirty Years’ War. His description of Gustavus Adolphus of Sweden as the "Lion from the North" was based on a reference to the Bible.
Carl Gustav Jung studied Paracelsus. He wrote two essays on him: one delivered in Einsiedeln, the village where Paracelsus was born, in 1929, and another in 1941 to mark the 400th anniversary of Paracelsus’s death in Zurich.
Many fictional stories about Paracelsus have been written. The first historical novel about him was published in 1830 by Dioclès Fabre d’Olivet. Robert Browning wrote a long poem titled Paracelsus in 1835. Meinrad Lienert published a story in 1915 about Paracelsus’s sword, claiming it was written by Gall Morel. Arthur Schnitzler wrote a play titled Paracelsus in 1899. Erwin Guido Kolbenheyer created a trilogy of novels called Paracelsus-Trilogie between 1917 and 1926. Martha Sills-Fuchs wrote three plays between 1936 and 1939, portraying Paracelsus as a prophet who healed the German people. A German film titled Paracelsus was made in 1943, directed by Georg Wilhelm Pabst. In the same year, Richard Billinger wrote a play about Paracelsus for the Salzburg Festival.
Finnish writer Mika Waltari’s book The Adventurer (1948) includes a scene about Paracelsus obtaining his legendary sword. Jorge Luis Borges wrote a short story titled "La rosa de Paracelso" (1983), and William Leonard Pickard wrote a novel titled The Rose of Paracelsus: On Secrets and Sacraments, inspired by Borges.
In the manga Fullmetal Alchemist, a character named Van Hohenheim is named after Paracelsus, a nod to his role as an alchemist. In the Japanese fighting game Guilty Gear, a battleaxe named Paracelsus is shaped like a key. The name likely honors the character’s wielder, a homonculus named A.B.A.
Paracelsus appears as a servant in the mobile game Fate/Grand Order. In the game Limbus Company, a researcher named Hohenheim is likely named after Paracelsus. In the 2026 BBC series Small Prophets, actor Mackenzie Crook mentioned that the idea of spiritual prophets in jars was inspired by a reference to Paracelsus in a book he read.
Works
German Wikisource has original writings connected to this article about Paracelsus. Due to the efforts of Karl Widemann, who worked for more than 30 years to copy Paracelsus's writings, many of these writings were not lost.