Why is it so hard to choose a typeface? Maybe it's because every single one designed represents months--even years--of teeth-gnashing by the designer, who saw some gap in the market and hoped to fill it with something brilliant.
But when you actually read it, it contains about 100 years of type-design history. The different branches in the decision tree represent entire schools of thought about the uses and the theory of type. And what's best, at the end of every decision tree, you get the typeface itself. Thus, you can see how terms like "humanism" are applied in type design--and the subtle differences between the Dutch and Swiss schools.
Check out the full-size version here.