Tectonic turns: How technology shaped healthcare over the decades

The earliest humans could only speculate about the source of their pain. Only later they learned to look for signs in the body such as increased temperature, inflammation among others as symptoms of sickness. As humans learned to live in groups, they started to have a specialist with eventual evolution into a formal profession of physician. Accidental experiments and observations could have led to the beginning of treatments. The earliest doctors relied heavily on observations and experience, progressing through a chain of trial and error so much so that a reliable doctor had always been believed to be old and frail.