who devised the technique syllogism to learn logic
Syllogism The use of syllogisms as a tool for understanding can be dated back to the logical reasoning discussions of Aristotle. Prior to the mid-twelfth century, medieval logicians were only familiar with a portion of Aristotle's works, including titles such as Categories and On Interpretation, works that contributed heavily to the prevailing Old Logic, or "logica vetus". The onset of a New Logic, or "logica nova", arose alongside the reappearance of Prior Analytics, the work in which Aristotle develops his theory of the syllogism.