Handbook of the History of Logic: - Fordham University Faculty

68 John Marenbon
went on to be further revised.
A rough modern parallel might make the nature of these twelfth-century
manuscripts more vivid. Imagine someone teaching an elementary logic course
who has produced a detailed handout, using a standard textbook which she feels
free to copy other logicians (she is just using it to teach, as was intended), and free
also to change wherever she can improve on the presentation or disagrees on the
stance the author has taken on a controversial issue, or where she finds a passage
out of date. Suppose, now, a student downloads the handout, but revises it in
line with extra comments the teacher makes in her lectures, and in the light of a
conversation he has with her about some issues which he found puzzling. Then,
three years later, when he is asked to lecture on the same subject, he turns to his
revised handout and uses it as the basis for his own lecture handout, but adding
some new material, reflecting his own views and some very recent controversies.
What results will be a document that, potentially, can tell a good deal about how
logic is taught, and about both teachers’ views — but it will not be easy, without
further information, to extract this information; and the wrong way to go about
it would be to try and find who is the document’s author.
3 THE ‘EARLY TWELFTH-CENTURY’ COMMENTARIES
A ‘Working Catalogue’ has been drawn up that aims to list all the commentaries
we know on the Isagoge, Categories and On Interpretation up to the end of the
twelfth century [Marenbon, 2000+], and there is also a (chronologically broader)
catalogue of On Topical differentiae commentaries and list of commentaries on the
other Boethian textbooks in [Green-Pedersen, 1984]. Although at the end of this
chapter I shall call into question the easy distinction that is often made between
logic from the beginning of the twelfth century and logic from the period 1115-40
(hence my scare quotes), there is certainly a group of commentaries from these
lists which researchers up until now have assigned to the period c. 1100-1115 and
distinguished from other, supposedly later pieces:
Literal commentaries
Commentaries on the Isagoge (P5), On Interpretation (H4), On Division (D7) in
MS Paris BN 13368 (edited in [Peter Abelard, 1969]);
Commentaries on the Isagoge (‘Disputata Porphyrii’ P7) (Edited in [Iwakuma,
1992, 74-100]), On Interpretation (H5) and On Topical differentiae (B1) in MS
Munich clm 14779;
The commentary on On Interpretation in MS Oxford, Corpus Christi College
233 (H7) (distantly related to H4 and H5);
Commentaries belonging to a collection of material in MS Pommersfelden Schlossbibliothek
16/2764, including two fragments of, or notes from, Isagoge commentaries
(P4a, P4b) (edited in [Iwakuma, 1992, 62-5]), a commentary on On Topical
differentiae (B3) [edited Hansen, 2005] and another fragment of one (B26),