Most people have heard of the eminent physician Hippocrates and his famous oath. But far fewer know of Shennong, Avicenna, and Andreas Vesalius – some of the lesser-known figures to have transformed the face of ancient medicine. Here we shed light on these men and others that may not be as popular as Hippocrates but have certainly had as much of an impact on changing our ancestor’s understanding of health care. And some of their work still continues to influence the medical field today!

Shennong, which means “God farmer” or “God peasant”, is a deity in Chinese religion, a mythical sage healer, and a ruler of prehistoric China. He is also believed to have refined the therapeutic understanding of pulse measurements and the practice of moxibustion (the medicinal practice of burning mugwort on particular parts of the body).

It is thought that Shennong lived from 2737 to 2697 BC, and legends say Shennong looked like a man but had a transparent stomach so he could see the effects of the plants he ingested. He is said to have eaten hundreds of plants while using his body to research their medicinal properties. The Huainanzi , a Chinese collection of debates from c. 139 BC, states that people were weak, sickly, starving, and diseased prior to the coming of Shennong.

The most well-known work associated with Shennong is The Divine Farmer’s Herb-Root Classic . It was first compiled near the end of the Western Han Dynasty (ca. 306 BC – 220 AD). The work lists numerous herbs that are graded based on rarity as well as their properties.

It is considered to be China’s earliest pharmacopoeia and includes 365 medicines derived from plants, minerals, and animals. The medicines are categorized as “superior” (non-poisonous and rejuvenating), “medium” (having some toxicity based on the dosage and exerting tonic effects), and “inferior” (poisonous but able to quickly reduce a fever and cure indigestion).

Al-Zahrawi was born in 936 AD, during the Islamic Golden Age , in El-Zahra, Andalusia, Spain. He received royal patronage and was recognized as a medical genius. For over 50 years, he served as the court physician.

But Al-Zahrawi insisted on seeing patients regardless of their financial status. By recording his treatments, he left behind a valuable medical treatise known as the Al-Tasrif li man ajaz an-il-talif (‘An Aid for Those Who Lack the Capacity to Read Big Books’), or simply the Al-Tasrif. This is a very important piece of work in the history of medicine, as it became the standard reference in Islamic and European medicine for over half a century.

Al-Zahrawi wrote about how to diagnose diseases and remarked that a good doctor should always rely on his own observations of a patient and his/her symptoms, rather than just accepting what a patient says. He also wrote about foods one should avoid, the maintenance of a healthy diet, and the use of food as part of a treatment plan.

However, the most influential part of the Al-Tasrif is the 30th volume which is dedicated to surgery. It is due to this part of his work that Al-Zahrawi has been dubbed the ‘Father of Modern Surgery.’ This volume contained detailed explanations for the procedures of certain surgeries, about 200 descriptions and illustrations of surgical instruments (the earliest of their kind in history), as well as a number of innovations that became widely used in operating theaters.

Asclepius was a demi-god son of Apollo who developed such incredible powers of healing under the that even Zeus felt threatened that he might achieve immortality for mankind. Asclepius was raised by Apollo, who taught him the art of healing. He was also tutored by Chiron, the wise centaur who inhabited Mount Pelion.

Asclepius became such an accomplished healer that he was able to bring one of his patients back form the dead. This alarmed Zeus, who felt that Asclepius’ skills could potentially grant mankind immortality, which would be a threat to the gods. So Zeus killed him with a thunderbolt.

Followers of his cult believed he had a preference for curing the ill while they were sleeping , so people would often sleep in temples of Asclepius. His legendary healing abilities are why the Rod of Asclepius continues to be a famous symbol associated with healthcare to this day. Although this object belongs to Greek mythology, it has continued to be used till this day as a symbol of medicine and healthcare.

Galen of Pergamum was one of the most renowned physicians of the Roman Empire. His medical works survived and dominated the theory and practice of medicine not only of the Roman world, but also of the Islamic world, and Medieval Europe .

After being abroad for a number of years, Galen returned to Pergamum in 157 AD, where he was appointed as a physician to the city’s gladiator. He was later summoned by Marcus Aurelius, the Roman Emperor, to serve as his court physician. Galen continued to serve in this capacity during the reigns of Caracalla and Septimius Severus.

Galen wrote hundreds of treatises. In the field of medicine, he is said to have compiled “all significant Greek and Roman medical knowledge to date”, and added his own observations and theories. Following the collapse of the Western Roman Empire, his works were mostly forgotten in the West.

In the Byzantine Empire and the Islamic world, by contrast, Galen’s works were featured prominently in the study of medicine. Thanks to this preservation of knowledge, Galen’s writings were able to find their way back to Western Europe during the Middle Ages.

The man considered to be the ‘father’ of toxicology is Philippus Aureolus Theophrastus Bombastus von Hohenheim, also known as Paracelsus. It is said that Paracelsus meant ‘equal to Celsus’ (referring to the Roman encyclopedist Aulus Cornelius Celsus), and the change in his name was meant to be an indication of Paracelsus’ desire to rival ancient medical authorities such as Celsus and Galen.

Paracelsus attended many of the most important European universities during his travels and gained practical medical knowledge while serving as a surgeon in the camps of various mercenary armies. Among his ‘heretical’ actions were his opposition to the revered Galeno-Arabic system, the burning of Avicenna’s writings in a public square, and his attack on the greed of apothecaries.

One of Paracelsus’ contributions to the field of medicine was the idea that pathological changes were caused not only by internal factors, i.e. the four humors, but also by external factors. These included ‘cosmic influences differing with climate and country, as well as ‘toxic matter originating in food’.

Paracelsus proposed that all natural substances have two types of influences –a helpful one, and a harmful one, which were separated by means of alchemy. This led to one of Paracelsus’ most famous adages, which is also the fundamental principle of classical toxicology, “Alle Dinge sind Gift und nichts ist ohne Gift, allein die Dosis macht es, dass ein Ding kein Gift ist.” meaning “All things are poison and nothing is without poison; only the dose makes a thing not a poison.” This has often been shortened to “The dose makes the poison.”

Known as Avicenna in the West, Ibn Sina was born in 980 AD in a village in modern day Uzbekistan and was a self-taught polymath. The scholar had a passion for knowledge and after studying math, he went on to explore astronomy, physics, philosophy (reading Aristotle in his teens), and medicine. While adept at all the fields, Ibn Sina found his calling in the medical profession, which he began practicing at the age of 18. Some have even called him the father of early medicine. A title he shares with Hippocrates.

He’s been credited with writing at least 130 books, the most influential being Al Qanun fil-Tibb , ‘The Canon of Medicine.’ This five-volume medical canon was translated to Latin in the 12th century and used as an important text in European medical courses until the 17th century.

Avicenna’s was the first known medical encyclopedia to identify tuberculosis, and it provided insight on contagious diseases spreading through water and soil. It also provided a basis for topics such as anatomy, pediatrics, and gynecology.

Andreas Vesalius was a physician and anatomist who lived during the 16th century AD. Up until this point of time, the standard authority on anatomy was the work of Galen. While Galen’s religious beliefs prevented him from cutting open a deceased human being, Vesalius did not share the same beliefs and his willingness to dissect humans marked the start of a new phase in the study of human anatomy.

In 1539, Vesalius’ work piqued the interest of a Paduan judge. This greatly benefitted Vesalius, as the judge allowed the anatomist to perform dissection on the bodies of executed criminals. With this, Vesalius was able to make repeated and comparative dissections of the human body. The results of Vesalius’ work can be seen in De humani corporis fabrica libri septem (translated as ‘On the Fabric of the Human Body in Seven Books’), which was published in 1543.

The text contained numerous woodcut illustrations that depicted human anatomy. These images are said to have influenced the way that human anatomy was depicted for centuries to come, so much so that they were often copied outright.

Ambroise Paré (c. 1510 – 1590) was a French barber surgeon who was a part of the Parisian Barber Surgeon Guild and served kings Henry II, Francis II, Charles IX, and Henry III. He invented several surgical instruments and was also a keen anatomist. To some, he is considered one of the fathers of modern forensic pathology and a pioneer in surgical techniques, battlefield medicine, and the treatment of wounds.

Besides being a medical professional, Paré was very much interested in monsters and his 1580s book ‘Monsters and Wonders’ is an illustrated treatise of the monsters he claimed to have observed himself as well as those drawn from his many readings.

The first category in ‘Monsters and Wonders’ describes “human monsters" and “appearances anomalies” which he related to pathological disorders . For example, he included a figure of two twinned females joined and united by the posterior parts. He noted beside this image “It is also the litters of several children, not only twins but on bisexuality: Children of two sexes or a couple of two androgynous children being joined back to back, one with the other.” In another entry he described a "Pregnancy with 11 fetuses.”

According to Chinese legend recorded in the Records of the Grand Historian, Bian Que was gifted with remarkable abilities from a deity. The story states that he was given a packet of medicine which gave him the ability to see through the human body. He thereby became an excellent diagnostician with his x-ray like ability. It is said that he pioneered pulse-taking, used anesthesia and even performed an organ transplant.

One legend stated that once, while visiting the state of Guo, Bian Que saw people mourning on the streets. Upon inquiring what their grievances were, he got the reply that the heir apparent of the lord had died, and the lord was in mourning. Sensing something afoot, he is said to have gone to the palace to inquire about the circumstances of the death.

After hearing of how the prince "died", he concluded that the prince had not really died, but was rather in a coma-like state. Using his acupuncture, he was said to have brought the prince back to consciousness. Prescribing the prince with medicine, the prince healed within days.

Top Image: ‘Ambroise Paré and the examination of a patient’ by James Bertrand. Source: Ji-Elle/ CC BY SA 3.0