Final answer:
An additional piece of outside information that supports Zinn's position is the concept of historical bias, which refers to the influence of perspectives and agendas on historical accounts. Recognizing historical bias is crucial for gaining an accurate understanding of historical events.
Step-by-step explanation:
An additional piece of outside information that would support Zinn's position is the concept of historical bias. This refers to the idea that historical accounts and narratives are often influenced by the perspectives and agendas of the writers or the dominant groups in power. In the case of Zinn's perspective, he argues that mainstream history has been shaped by a bias towards the ruling class and downplays the experiences of marginalized groups such as slaves and Native Americans.
Historical bias can be seen in various ways, such as the portrayal of Christopher Columbus as a hero and the omission of the impacts of colonization on Indigenous peoples. By recognizing and considering historical bias, we can gain a more comprehensive and accurate understanding of historical events, supporting Zinn's position.