Handbook of the History of Logic: - Fordham University Faculty

LOGIC AT THE TURN OF THE TWELFTH
CENTURY
John Marenbon
This chapter is not, like the others in the book, a survey of the logical doctrines
of a period, because I at least (and perhaps other scholars too) am not yet in
a position to write such a survey. It is simply a guide to the material, to the
technical problems it presents and some of the theories historians have elaborated
about it, along with an indication of a few of the philosophical themes which are
waiting to be explored. ‘The turn of the twelfth century’ is a deliberately vague
title, designed to indicate the between where the previous chapter finished and
Abelard’s work, the subject of the following chapter. But plugging this gap — even
as here, with a sponge and a nailbrush — is not a straightforwardly chronological
matter. Abelard’s Dialectica, the main subject of the next chapter, may have been
being written as early as 1110: a good deal of what is discussed here was probably
written no earlier, and some of the texts may in fact date from the 1120s or 1130s.
But the writings and writers discussed here have at least traditionally been seen
as providing the prelude to Abelard’s work. They form a separate group in their
methods and concerns from the writings of Abelard’s contemporaries and the later
twelfth-century schools considered in the final section of the next chapter. 1
1 THE CURRICULUM
The study of logic in this period was based around the Boethian curriculum that
had come into general use about a century before. Writing around the year 1110,
Abelard summarizes the situation neatly [Peter Abelard, 1970, 146]:
The Latin treatment of this art is furnished by seven books, the work
of three authors. For so far in the Latin world there are just two of
them by Aristotle, the Categories and On Interpretation, and one by
Porphyry . . . We generally use four by Boethius: On Division, the
Topics and his Categorical and Hypothetical Syllogisms.
1 This chapter was to have been written by Yukio Iwakuma, who more than anyone else has
studied the mostly unpublished material from which an idea of the developments in logic in
the years c. 1100 can be formed. I have adapted it, at two days’ notice, from a ‘Synthèse’
written for a Paris conference in February 2007 and made available on the web. I am grateful to
Yukio Iwakuma for letting me read his forthcoming ‘Vocales Revisited’, [Iwakuma, forthcoming-
B]. A revised version of the original, longer synthèse will be published in the Proceedings of
the conference [Rosier-Catach, Forthcoming-C]. I am very grateful to Irène Rosier-Catach for
allowing me to use this text in this volume.
Handbook of the History of Logic. Volume 2: Mediaeval and Renaissance Logic
Dov M. Gabbay and John Woods (Editors)
c○ 2007 Elsevier BV. All rights reserved.