If you want to know what people thought and did in the past then you need to read the documents produced in that time period. Any claims made about the past that do not take into account any historical sources would be entirely unwarranted. Even to use only a few primary sources would still limit one's understanding, scope and perspective of events. Ideally, a good historian wants to explore the words and views of a wide variety of people living in the time period who held different roles, backgrounds, biases, and motivations. Only when you see certain details that are shared in common between a variety of historical accounts of an event can you begin to corroborate your understanding of what really happened
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