Related על פסחים 6:2

...Hillel the elder expounded seven hermeneutical principles before the elders of Betheira: kal vachomer, gezeirah shavah, shnei kethuvim, kllal ufrat, kayotze bo bemakom acher ("the same applies elsewhere" — i.e., binyan av), davar halamed me'inyano (and davar halamed misofo).