382 THE HISTORY OF MEDIEVAL EUROPE critical attitude. "The master-key to knowledge is to keep asking questions," says this medieval Socrates. Conse- quently he puts one hundred and fifty-eight questions about the nature of God and other theological matters, and col- lects under each heading statements from patristic litera- ture both for (sic) and against (nori) the view in question. By thus showing the church fathers often in apparent dis- agreement, he demonstrated the need of further discussion and investigation in order to reach the truth in theology. He recognized that apparent obscurities might often be cleared up and that seeming contradictions might be recon- ciled by a more careful consideration of the passages or by excluding apocryphal works and by remedying the mistakes of copyists. But this, he would argue, simply shows the need of more intensive study. However, he further held that, except for the Bible itself, previous Christian writings were of unequal value and must not be unquestioningly accepted as absolute truth. If Abelard meant to discourage his age from consulting past authorities on all sorts of questions, he did not succeed. Scholasti- But his method of putting forward a problem for cism debate and solution and then finding all the state- ments pro and con bearing on the question that one could in past literature — this became a favorite method of medie- val teachers and writers. Only, instead of leaving the prob- lem unsolved, as the Sic et Non does, they went on to cope with the arguments on both sides and to attempt to reach a correct solution. Such writings, together with commen- taries on the authorities, became the staple products of medieval scholasticism. Gratian's Harmony of Conflicting Canons was such a work. A year or two after it came out, Peter Lombard, who had attended Abelard's lectures, pub- lished his famous Sententice, henceforth the standard text- book in scholastic theology. The title Sententice, commonly translated as "Sentences," in this case refers to the "opin- ions" or authoritative utterances of the church fathers upon the various questions of the Christian faith, which Peter has collected, condensed, and classified in one volume.