The fourth step to include multiple sources in your historical argument is to compare and contrast them critically and constructively. Rather than simply listing or describing your sources, you should analyze how they differ or agree on the past, how they complement or contradict each other, and how they reveal the complexity and diversity of the past. To do this, consider their similarities and differences, strengths and weaknesses, as well as opportunities and challenges. Examine how your sources agree or disagree on the facts, events, causes, effects, or interpretations of the past. Analyze their reliability, accuracy, and credibility; how they use or misuse evidence, reasoning, or arguments; and how they address or ignore their limitations. Finally, consider how your sources offer or pose opportunities and challenges for your historical argument and for the broader historical context. This will help you enrich or complicate your understanding and interpretation of the past, as well as raise or answer new or existing questions about the past.