doctors, history of

Throughout the history of medicine, the role, status, and required qualifications of a doctor have changed. At various times doctors have been gods, priests, or scientists, or even viewed as a waste of money or the agents of death. Doctors have relied on prayer, herbal potions, observation, cleanliness, or scientific knowledge to treat or prevent illness, with varying success. Although with modern knowledge, certain treatments seemed guaranteed to shorten rather than prolong life, the common aim of all doctors in the history of medicine has been to cure their patients.

Prehistoric doctors The first doctors were the shaman or medicine men who practised the prehistoric medicine of the Stone Age. Medicine men combined the worlds of religion and rational medicine. They used some rational or practical techniques, such as setting broken bones in clay or using herbal remedies made from local plants such as coca or orchid bulbs. At the same time they used religious rituals to treat any illness that they could not understand. Religious ceremonies and techniques such as trepanning (drilling a hole in the skull) were used to drive the evil spirit causing the illness away. Skills were handed down by example and word of mouth as there were no schools or written language for the spread of information. Medicine men were accepted as doctors as they were the closest people in the tribe to the gods, and gained their powers of healing from them.

Ancient Egyptian doctors In ancient Egyptian medicine the skills and knowledge of doctors developed from the legacy of the prehistoric age. Doctors in ancient Egypt were usually also priests, and religious rituals continued to be used alongside rational treatments as both were believed necessary for a cure. Important deities invoked in medicine included Imhotep, the god of healing, who was formerly doctor to Pharaoh Zoser in the 3rd millennium BC, and Thoth, god of wisdom and learning.

A system of medical training was established in the temples and a written language developed using hieroglyphics. Medical treatments were recorded on papyri such as the Papyrus Ebers and the Papyrus Edwin Smith. The standard work used by Egyptian doctors was the Book of Thoth, a collection of ritual and rational treatments. The religious practice of mummification, in which the organs of the body were removed, helped Egyptian doctors to gain an understanding of human anatomy, although dissection was banned for religious reasons. However, Egyptian doctors began to practise basic surgery such as the removal of growths on the skin or cataracts from the eyes. Egyptian doctors believed that illness was often caused by the body's channels becoming blocked because of rotting food in the stomach, a practical theory based on their observation of the River Nile. Patients affected were given emetics to make them vomit or laxatives to loosen their bowels and clear the blockage. Medical preparations included ingredients such as honey, salt, and dates.

Like the prehistoric medicine men, Egyptian doctors continued to combine religious and practical ideas. However, their settled civilization, trading links, and written language allowed them to investigate and observe illness further, develop new and more rational treatments, and create records to pass on knowledge, while still believing that the gods played a major role in the cause and cure of illness.

Greek doctors In ancient Greek medicine doctors were able to build on the ideas of the Egyptians by adding a more philosophical approach to knowledge. Greek doctors continued to practise both spiritual and rational medicine, but there was more separation of these traditions. The most influential Greek doctor was Hippocrates, who practised in the 5th and 4th centuries BC. He believed that illness was not caused by the gods, but was the result of the body's elements becoming out of balance with the environment and developed the theory of the humours (four body fluids: blood, phlegm, yellow bile, and black bile). Hippocrates used the rational method of clinical observation to record the progression of an illness, and said that doctors should only prescribe when they fully understood the disease of their patient. His theory of humours was developed by other physicians and philosophical theorists such as Aristotle. Doctors treated patients by attempting to balance their humours with the seasons.

The rational Hippocratic approach co-existed with the tradition of spiritual medicine developed in the cult of Asclepius, the Greek god of healing. Patients visited his temples where the priests were doctors, and treated patients using rational ideas such as healthy diet and exercise as well as applying treatments made of natural ingredients. The patients' dreams were interpreted as visitations by Asclepius, and a focus for diagnosis and the prescribing of any treatment. The priest-doctors believed that Asclepius helped patients to recover, and combined the rational and spiritual in their treatment.

Priest-doctors were trained in the temples of Asclepius, the main centre being at Epidaurus, while Hippocratic doctors were trained in schools of medicine, such as that established by Hippocrates on the island of Kos. Medical theories spread through books on medicine and philosophy, and through attendance at the schools.

Roman doctors The Romans conquered the Greeks during the formation of the Roman Empire, and many of their ideas were adopted by the doctors of Roman medicine. The majority of doctors working in the Roman Empire were Greek, and many Roman doctors were trained using the writings of Hippocrates. Although formal training did exist for doctors, such as apprenticeship to another doctor, anyone could call themselves a doctor in ancient Rome. Many women worked as doctors in ancient Rome, usually attending to the needs of other women. Doctors were provided free to the poor in towns, as part of the Roman Empire's extensive public health system. Many doctors became surgeons in the Roman army, and developed their skills in the army hospitals spread throughout the Empire.

Roman doctors often prescribed exercise and cleanliness as part of their treatments. The theory of the four humours continued during the Roman period, but was developed by Galen, a Greek physician working in Rome in the 2nd century AD whose ideas were to dominate European medicine for over 1,500 years. Galen developed the theory of treatment by opposites to restore the balance of the humours. Romans would consult a doctor and also make offerings to gods such as Salus, the Roman goddess of safety, who was identified in the 3rd century BC with the Greek goddess of healing Hygieia. Temples of Asclepius were also used, copied from the Greeks.

Medieval doctors Medieval medicine was mainly marked by the regression and stagnation of medical knowledge and practice. Following the end of the Roman Empire in AD 476, Europe entered the Dark Ages, and the skills and knowledge of doctors regressed for over 500 years. The books and manuscripts of the ancient Greeks and Romans were lost, destroyed, or remained unread in the collections of the Roman Catholic Church, and the training of doctors stopped. Physicians knowledgeable in the arts of Hippocrates and Galen were rare, and most people returned to a reliance on local wise people for treatment, and homemade cures or medicines. Many of these medicines worked as they were based on knowledge handed down over the centuries, but the period still represented a decline in the importance and knowledge of doctors.

From the 11th century the training of doctors was revived in Europe. The ideas of Hippocrates and Galen were rediscovered through the manuscripts still held by the church and through increased contact with the Muslim world, where medicine had continued to flourish during Europe's Dark Ages. The church began to promote the ideas of Galen because he believed that Nature expressed a divine purpose. Medical schools and universities, such as Salerno, Paris, and Padua, were established under the control of the church from the late 10th century. Doctors began to be trained again. By the 13th century it was illegal in many countries in Europe for people to call themselves doctors, or physics, without formal training.

The doctors trained during this period used the four humours of the ancient Greeks as the basis of much of their treatments. Blood-letting and purging to restore the balance of the humours were common. The use of urine charts to diagnose illness was related to the Hippocratic technique of clinical observation. Doctors also had to be knowledgeable about the movement of the planets and their impact on disease. The role of religion was still important, as the church controlled the universities and medical schools, and the belief that disease was a trial or punishment from God continued to influence many doctors in the Middle Ages.

Understanding of the human body was hindered by the authorities' insistence that Galen's work was infallible. His theories about the anatomy of the human body were taught to medical students as fact, although many of his ideas were incorrect as they had been deduced from studies of animals; Roman religious belief had banned human dissection. Dissection of the human corpse was still prohibited, except for the bodies of executed criminals when dissection was considered part of their punishment. Even then, dissections were only carried out to uphold Galen's theories.

Despite the increasing professionalism of doctors, they remained unable to deal with the Black Death, an epidemic of bubonic plague in the mid-14th century that killed between one-third and half of Europe's population. Spiritual explanations for this disaster remained stronger than anything a rational doctor could offer.

However, by the end of the Middle Ages a form of doctor similar to the modern scientific professional was beginning to emerge. Increasing numbers of doctors were challenging the ideas of Galen, and the stranglehold of the Catholic Church over medicine was being slowly broken.

Renaissance doctors The Renaissance (15th–mid-18th centuries) saw great advances in the skills and knowledge of European doctors. The combination of the printing press, better anatomical illustrations, and the spirit of discovery that characterized the Renaissance had a dramatic impact on medicine. Doctors of Renaissance medicine developed greater understanding of the body than at any previous age in European history. Physicians and anatomists such as Andreas Vesalius and William Harvey disproved the ideas of Galen that had controlled the practice of medicine for over 1,500 years. Medical students were able to study from new medical books with life-like illustrations made from thorough investigative dissections, and were trained in universities that, by the end of the Renaissance, allowed the dissection of human corpses. The invention of the printing press gave doctors all over Europe rapid and relatively inexpensive access to books, allowing new ideas to spread more quickly.

Spiritual explanations for disease were not totally dropped, but rational ideas became the dominant force following the work of doctors such as Paracelsus, Johannes Guinter, Vesalius, Geronimo Fabricius, Matteo Realdo Colombo, William Harvey, Thomas Sydenham, and Ambroise Paré. The books published by these doctors transformed the understanding of medicine. In 1531 Guinter published a Latin translation of Galen's On Anatomical Procedures in which Galen stressed the necessity to dissect the human body, challenging the ban on dissection. Vesalius's De humani corporis fabrica/On the Structure of the Human Body (1543) showed the value of combining illustrations and text in books. This change of presentation in medical books had a major impact on the skills and knowledge of doctors in the Renaissance. Universities did not teach students surgical techniques, these had to be learned from apprenticeship to a practising surgeon, but the advances in anatomical knowledge and their description and illustration in medical texts enabled increasingly complex surgical procedures to be carried out.

Ordinary people continued to use homemade remedies or the traditional treatments of local people without formal training, but the skills and knowledge of the most educated doctors was reaching new heights. Although the church and the old medical establishment continued to support the theories of Galen, the advances made during the Renaissance eventually changed the entire profession.

Doctors in the 19th century The scientific discoveries of the Renaissance and the Industrial Revolution (1750–1900) enabled doctors of 19th-century medicine to advance their knowledge and skills still further. By 1900 germs, inoculation, antiseptics, and gas anaesthetics had been discovered. Doctors were able to give vaccinations against diseases such as smallpox that had previously killed thousands. The training of doctors was improved, and women were finally allowed to train on an equal basis. The first woman doctor in the USA was Elizabeth Blackwell in 1849, and the first in the UK was Elizabeth Garret Anderson in 1865. Public health problems were increasingly tackled after the German bacteriologist Robert Koch discovered the bacillus that caused cholera in 1883.

Governments and wealthy individuals provided money for doctors to research diseases. Their ideas could be instantly communicated using new technologies. The technique of observing symptoms, recognizing the illness, and then treating according to known effective remedies was enhanced by increased understanding of disease and the development of new drugs. Louis Pasteur's discovery of micro-organisms in fermentation, and the subsequent development of his germ theory of disease in the 1860s, was one of the most important medical advances in history. It offered final proof that disease was caused by bacteria found in the environment, and not by the actions of God. Although such revolutionary ideas were not immediately accepted universally, the success rates for doctors increased. Doctors worked in an atmosphere of ever-increasing knowledge and were finally able to reject the flawed ideas of Galen. Stronger microscopes allowed doctors to isolate bacteria from diseases that had been regarded as untreatable in previous ages. Between 1880 and 1898 the causes of eight of the most deadly diseases were discovered – typhoid fever (1880), tuberculosis (1882), cholera (1883), tetanus (1884), pneumonia (1886), meningitis (1887), bubonic plague (1894), and dysentery (1898). By 1900 doctors had rejected the role of religion in causing disease, and rational techniques based on scientific proof were dominant.

Doctors in the 20th and 21st centuries In the 20th century doctors finally became available to the whole population of Western Europe, regardless of the patient's ability to pay. The 20th century saw the discoveries and developments of the previous centuries spread more widely than ever before. Further advances were made in scientific knowledge and skills, such as the work of Alexander Fleming, Howard Florey, and Ernst Chain on penicillin and there were enormous advances in 20th-century medical technology.

Surgical procedures advanced. After the development of sodium citrate in World War I, doctors were able to carry out blood transfusions without the need for the donor to be present. Harold Gillies and Archibald McIndoe developed plastic surgery during world wars I and II. The 20th century also saw the first organ transplants; the first heart transplant was carried out by the South African surgeon Christiaan Barnard in 1967. Doctors were able to treat infertility in humans using IVF, the egg and sperm being joined in the laboratory and then transplanted to the uterus, and in 1978 the first ‘test-tube’ baby was born in the UK.

The advances made by doctors in the 20th century enabled the treatment of almost any disease or medical problem. However, new conditions including AIDS (acquired immune deficiency syndrome) and MRSA (methicillin-resistant staphylococcus aureus; an infection that causes serious problems in hospitals) proved that doctors were unable to solve all the problems of a disease.

Doctors were increasingly faced with diseases caused by people's lifestyles, such as heart disease. Deaths due to cancer continued at high rates despite the progress made by doctors in the 20th century. Lung cancer death rates halved in the UK in the second half of the 20th century, but thousands still died each year.

New ethical issues emerged in medicine. Animal testing enabled the development of new techniques and medicines, but many argued that such tests were unacceptable. Following the investigation of DNA (deoxyribonucleic acid) in the 1950s by Rosalind Franklin, James Watson, and Francis Crick, scientists developed the ability to manipulate genetic material, culminating in techniques of gene therapy and the ability to clone mammals and possibly humans. The ethics of such techniques continue to be questioned despite the huge medical benefits that gene therapy can potentially offer. Doctors at the beginning of the 21st century were possessed with the ability to treat more illnesses than at any time in history, but were also faced with more profound ethical dilemmas than before. Spiritual healing and alternative medicine remained in use by many people, and many modern doctors began to accept the place of holism (treatment of the patient as a whole) in medical practice.

Change, continuity, and progress The role, status, beliefs, and abilities of doctors have changed over the thousands of years since the Stone Age. Spiritual explanations for illness and disease have declined in importance, to be replaced by practical and rational medicine. Doctors have ceased to be priests, and the science of medicine has become all powerful. Although herbal remedies have remained in use throughout the history of medicine, the way in which doctors have been able to understand why certain herbs work has changed. The ideas of certain doctors such as Galen remained dominant for long periods, and the discoveries of others, such as Vesalius and Pasteur, have revolutionized medical practice. What remains true of the profession from the prehistoric medicine man to the modern scientific specialist of today is that the job of a doctor is to cure their patients using any available knowledge and permissible technique.