3 ideas
7726 | Aristotelian logic dealt with inferences about concepts, and there were also proposition inferences [Weiner] |
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. | |
From: Joan Weiner (Frege [1999], Ch.3) | |
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? |
3061 | Anaxarchus said that he was not even sure that he knew nothing [Anaxarchus, by Diog. Laertius] |
Full Idea: Anaxarchus said that he was not even sure that he knew nothing. | |
From: report of Anaxarchus (fragments/reports [c.340 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.10.1 |
2667 | A false object might give the same presentation as a true one [Arcesilaus, by Cicero] |
Full Idea: Arcesilaus said that no presentation proceeding from a true object is such that a presentation proceeding from a false one might not also be of the same form. This is the one argument that has held the field down to the present day. | |
From: report of Arcesilaus (fragments/reports [c.275 BCE]) by M. Tullius Cicero - Academica II.24.77 |