The advantages found in history seem to be of three kinds, as they result either from the mere situation of the climate and country or from the form of government and of the character of the people, or from those finer principles and morals, which may be called the recommendations of philosophy.
Well, the first rule is that you can’t really know anything if you just remember isolated facts and try and bang ’em back. If the facts don’t hang together on a latticework of theory, you don’t have them in a usable form.