The scientific attitude of humility is most likely to be undermined by

The scientific attitude of humility is most likely to be undermined by "the Hindsight Bias".

Hindsight bias is a term utilized in psychology to clarify the inclination of individuals to overestimate their capacity to have anticipated a result that couldn't in any way, shape or form have been anticipated. Generally, the insight into the past inclination is similar to stating "I knew it!" when a result (either expected or startling) happens – and the conviction that one really anticipated it accurately.  

the historians cited in the article all agree with one another about the cause of the civil war. despite coming from different backgrounds and cultures, the historians agree that slavery was the root cause of the civil war. the fact that all these historiansgenerally agree with one another makes their shared viewpoints more reliable and valid, especially because the historians have different backgrounds and all work for the well-respected institutions of howard university, clemson university, and the university of colorado.