Final answer:
The two main reasons for altering the past are causation, which interprets the driving factors behind events, and interpretation, which evolves as new information and perspectives arise about historical events.
Step-by-step explanation:
The two main reasons for altering the past relate to causation and interpretation. Historians seek to understand the driving forces behind historical events, looking at both immediate and long-term circumstances which require them to consider levels of causation. These include personal motives, societal pressure, and the larger cultural or political milieu. As historians analyze an event, they rank causes in importance which shapes our understanding of history. Additionally, interpretations of historical events can change over time, as new information becomes available or when perspectives shift, reflecting a society's evolving values and experiences.
Interpretation plays a central role in the field of history, and by viewing history through various lenses, we gain a clearer picture of the past. However, historians work to minimize bias in order to present an accurate reflection of the past, which is crucial for history to fulfill its function of truly representing our shared human experience. Elements such as bias and value systems are considerations that historians must recognize and navigate to produce a balanced historical narrative.