Handbook of the History of Logic: - Fordham University Faculty

The Assimilation of Aristotelian and Arabic Logic up to the Later Thirteenth Century 311
4.4 The Topics
Before the thirteenth century the discussion of Aristotle’s Topics was completely
dominated by Boethius’ De differentiis topicis, which is not really a commentary
of Aristotle’s work, but a mix of Aristotle and Cicero. The first extant Latin
commentary on Aristotle’s Topics is from c. 1235. Naturally, Boethius remained
influential well into the thirteenth century; although they gradually stopped commenting
on his work.
In the first chapter of the first book of the Topics, Aristotle writes (100a10-20):
The goal of this study is to find a method with which we shall be able to
construct deductions (syllogisms) from acceptable premises concerning
any problem that is proposed and – when submitted to arguments
ourselves – will not say anything inconsistent.
This is the method of dialectics. It is an argumentative method in dialogue form
between a questioner and an answerer. These two first agree upon a problem (a
question), which usually is a proposition expressing a well accepted opinion. Next
the questioner puts forward questions to the answerer, which he/she answers with
‘Yes’ or ‘No’, that is, he/she accepts the propositions proposed or denies them.
The accepted question or proposition then becomes premises in the argument. The
purpose of this exercise is to examine the agreed upon problem and show that it
leads to inconsistencies or at least to opinions not acceptable to the answerer.
Aristotle never tells the reader what a topic (topos) is, but he gives examples
in Books II-VII of the Topics, but as many commentators have observed it is not
always helpful to have lots of examples. The problem has been to understand
what they are examples of. In the Rhetorics, Aristotle gives us some help. There
he notes that the topoi are “that under which many arguments fall” (1403a17-
8). This suggests that the topoi are classifications of arguments, that is, they are
argumentative forms.
The Latin name for a topic is a locus. Boethius defines a locus as: “that
by which the argument is settled, or that by which from a proposed question
the argument is drawn out.” 72 According to Boethius, it is hence about finding
arguments from particular questions (or premises) to conclusions, which means
that it is by finding the locus or the middle term that we can find the argument
that gets us from question to conclusion.
Strictly speaking a question is of the form ‘Either A is B or A is not-B’, and
the problem is which disjunct should be accepted? The question is answered by
an argument, and Boethius understands it as being syllogistically structured, but
what he presents are not valid syllogisms. In syllogistics, the problem is, once
one knows the system, finding the middle term, and the theory of the topics
systematises the process of finding the middle term. There is no standard way
of doing this though, since they will always depend on the particular argument.
72Boethius, De differentiis topicis in [Stump, 1978, 30]. The translation is here slightly modified.