“Almost every historian has his or her own personal list of the characteristics of historical thinking, but abilities that come up again and again are:
1. The ability to tell the difference between a primary and a secondary source.
2. The ability to “source the source”; that is, figure out who created the source, when it was created, and so on.
3. The ability to obtain information about the authority of the source and to assess that authority in light of other evidence.
4. The ability to set sources in their proper chronological order and to understand why that ordering is important.
5. The ability to construct an original argument based upon evidence from various sources.
6. The ability to recognize the strangeness of the past without being put off by that strangeness.
7. The ability to make comparative judgments about evidence.
8. The ability to recognize what one does not or cannot know from the evidence at hand.
9. The ability to understand that events are understood differently by different people.
10. The ability to triangulate between and among sources.
11. The ability to ask probing questions—not just what happened, but why did it happen this way and why didn’t it happen that way?
12. The ability to recognize the role of causality.
13. The ability to critique evidence both on its own terms and in terms of its value to a larger analytical project.
14. The ability to recognize lines of argument in historical thought.
15. The ability to present the past in clear ways, whether in writing or in other media, saying what can be said and not saying what cannot.”
Kelly, T. Mills, Teaching History in the Digital Age, University of Michigan Press 2013, pp 22-23.