Full Idea
Till the nineteenth century, it was a common view that Aristotelian logic could evaluate inferences whose validity was based on relations between concepts, while propositional logic could evaluate inferences based on relations between propositions.
Clarification
Syllogisms are Aristotelian, and 'if p then q, p, so q' is propositional
Gist of Idea
Aristotelian logic dealt with inferences about concepts, and there were also proposition inferences
Source
Joan Weiner (Frege [1999], Ch.3)
Book Reference
Weiner,Joan: 'Frege' [OUP 1999], p.26
A Reaction
Venn diagrams relate closely to Aristotelian syllogisms, as each concept is represented by a circle, and shows relations between sets. Arrows seem needed to represent how to go from one proposition to another. Is one static, the other dynamic?