The History of Medicine and Chemistry

Medicine Before the Scientific Revolution

• Medicine was largely based on Galen's teachings, a 2nd-century Roman physician, who believed sickness was caused by imbalances in the four humors and temperaments of the body.
• Treatments during the Middle Ages were often primitive and detrimental, such as bloodletting, which was believed to cure illnesses caused by excess blood in the body.
• This practice was even used on President George Washington, potentially leading to his death in 1799.

Chemistry Before the Scientific Revolution

• People in the Middle Ages believed in the Aristotelian model, which stated that all substances were composed of four basic elements: fire, air, water, and earth.
• Alchemy was a prevalent pursuit, attempting to turn baser metals into gold or silver.

New Ideas: Paracelsus

• Paracelsus, a 16th-century Swiss-born chemist, favored experimentation and rejected Galen's theories, believing diseases were caused by 'bad seeds'.
• He publicly burned copies of Galen's work and advocated for a new approach to medicine.

New Ideas: Andreas Vesalius

• Vesalius, a Flemish contemporary of Paracelsus, made numerous discoveries about the human body through dissections.
• He correctly identified the human heart as having four chambers, contradicting Galen's claim of two chambers.
• Vesalius created the world's first medical textbook, De Humani Corporis Fabrica, in 1543.

New Ideas: Iatrochemists

• Iatrochemists focused on preparing substances and solutions in the purest way possible, making extensive notes on their experiments.
• They consulted and released their findings across the early modern scientific world.

New Ideas: Robert Boyle

• Robert Boyle, an Irish-born chemist, was an empiricist who believed only in experimentation-based knowledge.
• He is famous for discovering Boyle's Law, which states that the volume of a gas varies inversely with pressure.

New Ideas: William Harvey

• William Harvey, an English physician, announced his discovery that blood was continuously pumped throughout the body by the heart.
• He discovered that the body contained a fixed amount of blood, contradicting Galen's teachings.

Medicine and Chemistry Moving Forward

• The work of early physicians and chemists laid the foundation for modern understanding of the human body and composition of substances.
• Later achievements, such as vaccination and germ theory, were built upon the empiricism pioneered by these early scientists.