Remembering the past
The past is everything that ever happened to anyone, anywhere. No textbook, museum or website could hold all of it, so historians have to choose what to keep and what to leave out.
Medicine shows the problem clearly. Over thousands of years, millions of people have treated the sick. There were healers, midwives, herbalists, army surgeons, nurses and laboratory scientists. Yet most medical histories name only a small group, such as Hippocrates, Galen, Vesalius, Paré, Harvey, Jenner, Pasteur, Koch, Lister, Nightingale, Fleming and Florey.
Those names were chosen by people, using reasons. Once you know the reasons, you can test them, argue with them and sometimes overturn them. Historians judge how much a person mattered, and defend that judgement with evidence.
The value historians give to a person, event or development when deciding what is worth remembering and studying. Significance is a judgement made with criteria. It is not a fixed fact about the past.
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