Peter Abelard: Quotes about the truth

Prologue as translated in Readings in European History, Vol. I (1904) edited by James Harvey Robinson, p. 450
Sic et Non (1120)
Context: There are many seeming contradictions and even obscurities in the innumerable writings of the church fathers. Our respect for their authority should not stand in the way of an effort on our part to come at the truth. The obscurity and contradictions in ancient writings may be explained upon many grounds, and may be discussed without impugning the good faith and insight of the fathers. A writer may use different terms to mean the same thing, in order to avoid a monotonous repetition of the same word. Common, vague words may be employed in order that the common people may understand; and sometimes a writer sacrifices perfect accuracy in the interest of a clear general statement. Poetical, figurative language is often obscure and vague.
Not infrequently apocryphal works are attributed to the saints. Then, even the best authors often introduce the erroneous views of others and leave the reader to distinguish between the true and the false. Sometimes, as Augustine confesses in his own case, the fathers ventured to rely upon the opinions of others.

Introduction as translated in Readings in European History, Vol. I (1904) edited by James Harvey Robinson, p. 451
Variant translation:
Constant and frequent questioning is the first key to wisdom … For through doubting we are led to inquire, and by inquiry we perceive the truth.
Prologue as translated in A History of Education During the Middle Ages and the Transition to Modern Times (1918) by Frank Pierrepont Graves; 2005 edition, p. 53<!-- translation of Prima sapientiae clavis definitur, assidua scilicet seu frequens interrogatio … Dubitando enim ad inquisitionem venimus; inquirendo veritatem percipimus. -->
Sic et Non (1120)
Context: I have ventured to bring together various dicta of the holy fathers, as they came to mind, and to formulate certain questions which were suggested by the seeming contradictions in the statements. These questions ought to serve to excite tender readers to a zealous inquiry into truth and so sharpen their wits. The master key of knowledge is, indeed, a persistent and frequent questioning. Aristotle, the most clear-sighted of all the philosophers, was desirous above all things else to arouse this questioning spirit, for in his Categories he exhorts a student as follows: "It may well be difficult to reach a positive conclusion in these matters unless they be frequently discussed. It is by no means fruitless to be doubtful on particular points." By doubting we come to examine, and by examining we reach the truth.