Book VIII of the Topics, Treatise III, Chapters I-III.

TREATISE III.

IN WHAT WAY DIALECTIC IS FOR EXERCISING.

CHAPTER I.

On teachings pertaining to exercise, both formal and rational.

Now dialectic has been handed down according as it is for inquiry and for disciplines according to philosophy, and dialectic has also now been handed down according as it is for obviation, both from the side of the opponent and from the side of the respondent. Therefore now, lastly, it is handed down according as it is something for exercise and meditation, which is an act of memory; and the same things are frequently for exercise and for meditation of such speeches as avail for exercise. The first teaching, formal and contributive to exercise, is that one must become accustomed so that he knows how to use a conversive syllogism, so that he also knows how such disputed speeches are converted. For by knowing how to use conversive syllogisms, we shall also have ourselves more suitable for that which is said, and we shall present ourselves as more prepared, and from speeches taken in few things we shall have several speeches making for the proposed thing. But the reason of this is that to be converted, or to use a conversive syllogism, is that someone, transferring the conclusion of the first syllogism already syllogized into another syllogism and into the opposite to the conclusion, posits that opposite with the remaining premise, or with the other of the premises, to take away one of those premises which were given in the prior syllogism. For if the conclusion is not true and the opposite of the conclusion is syllogized with one of the premises, the opposite of the other premise of the first syllogism will necessarily follow; and this indeed is necessary if this is conceded, that when all the premises with the first conclusion have been posited and conceded, it was necessary that the conclusion be or follow from the premises: for then the opposite follows when the opposite of the conclusion has been posited with the other premise.

But in giving teachings according as the exercitative is for determining a position, we say that for every position of the respondent one must consider the argument terminating it to affirmation, that it is so as it is posited, and arguing to negation, that it is not so as it is posited. But after disputation has been made toward each part, then one must seek to find the solution: for by doing this frequently, it happens at once that one is exercised in interrogating or opposing and responding; and if we have no one else for disputing by syllogism, nevertheless we shall have ourselves to exercise ourselves in this way.

But another teaching is that, when arguments have thus been introduced to each part and weighed alternately, one must choose which arguments to the same opinion are more strong, whether those are toward the affirmative of the opinion or toward the negative. For this contributes much suitability for knowing concerning anything, and has a great help through exercise for arguing to any proposed thing: because someone is suitable through exercise for arguing both that it is thus affirmatively and that it is not thus negatively. For from such teachings observation happens, and the faculty happens to be made from things observed; and it also has a help for knowing concerning anything according to philosophy speculative prudence, that is, foresight, so that in anything there may be foreseen what is true and what is false; and to be able to inspect in individual things what happens to be said on both sides, that is, toward each part of the contradiction, concerning each thing from hypothesis, that is, supposition, that is, from such propositions as are supposed so that we may use them as principles. For this is no small instrument for those things which have been said: from this, then, what remains and is left and caused is for us to choose by reason one of the contradictories, whichever it is that is true. But for this choice someone must be of good natural ability according to the power of rational nature. To be of good natural ability is to be able from native capacity to choose the true in anything and flee the false, because those who are well born, that is, those to whom this is well inborn, can do this well; because natural ability is said as “inwardly born,” and this is the one who has subtle spirits, ready animal operations, and a good collative reason. For those who love the true as applicable to their nature, and who hate the false which is brought forward as hostile to their nature, easily discern the best in all things through art helping nature.

But another teaching is that the one who wishes to be exercised must know disputative speeches availing for those problems which often occur; for these are common and availing for many things, and especially concerning proper propositions which we use for those other things as principles, because these are constructions and avail for many things. In these propositions the respondents themselves often contend with opponents, because they avail in many problems.

Further, another teaching is that one must be suitable in terms, that is, definitions and principles, so that he retains by memory many definitions of many things and many principles, and in the more probable and in the first or prior things he must be prompt: for these, as Aristotle says, are smallest in quantity and greatest in power, and through such things many syllogisms are made.¹ But one must try especially to retain chiefly in memory those things into which speeches, that is, argumentations of disputants, often fall as into principles in many problems; just as in geometry, before the work of theorems about elements, that is, principles, the geometer must be exercised, because into those, as into principles, the demonstration of theorems falls; and as in numbers, before the generation of proportionable numbers, someone must have himself prompt about the principal numbers from which they arise, as is clear in the beginning of arithmetic; for this contributes much to knowing another number multiplied from a principal number and generated. Likewise in rhetorical speeches one must know useful propositions and allegations, and store principles in a memorial treasury, as it were; and immediately when remembrance returns to them, they make the same things be remembered, and syllogistic propositions, that is, universal and common ones, do this more than others, through which there is syllogistic passage, because those exercising inspect them as determined according to number. But singular propositions are not syllogistic, since they are not determined according to number, and therefore cannot be remembered. But in such memorable things, the universal is more to be stored in memory than the speech, that is, the whole argumentation; for to be moderately suitable concerning principle and hypothesis, that is, position, is difficult, that is, it is difficult for someone to be even moderately suitable concerning the proper principles of each thing and the proper propositions. And therefore common things must be retained by memory.

CHAPTER II.

About which speeches one must especially be exercised.

Further, one who wishes to exercise must especially study to make one speech or one argumentation into several and very many, if it can be done, and to become accustomed to doing this. But that one speech becomes several for opponents will be done most obscurely or most latently by hiding universals and higher proposed things while departing from the proposed thing. The teaching for this, that many argumentations and propositions be made, will happen if some one of the opponents departs very much from those particulars about which, or of which, the speech is, that is, about which or concerning which he then disputes; because by thus departing, very many propositions are made latently in prosyllogisms, and syllogisms of many middles; and therefore those opponents will be powerful in many speeches who most of all and from custom can suffer them. For memory is a passive and receptive position, and habituation is a certain undergoing of accidents by becoming accustomed; and therefore he who has been affected by these things, by memory and habituation, through the very reception of such a habit will be most powerful for making such things. But the example of this is that this be proposed, that there is not one discipline of contraries; one departs into this most common thing, that there is not one discipline of several things. For by thus departing he will have that in those things which are relatives there is not one discipline, and in conjugates it will be similar, and in all things which are several, immediately it will be held that there is not one discipline.

But in such a teaching for multiplying, one must make remembrance of speeches which are especially universal or are universals, because into these one must especially depart, although the opponent himself had been disputing particularly, that is, toward a particular. For thus it is possible to make one speech into several in prosyllogisms. Likewise it is also in rhetorical enthymemes, that several speeches are made by departing from a particular cause into a universal; and then there will be several rhetorical places taken from the name and the circumstances of the business. But the same opponent must as much as possible flee or depart into the universal, and must bring many syllogisms or prosyllogisms; and the opponent must always consider about what things he disputes, if they are disputed in several speeches: for all particular speeches are disputed in universals, and not conversely the universal in particulars. And even in particular speeches there is universal demonstration, because the particular is demonstrated through the universal; and it is not possible to demonstrate anything except through the universal, because without a universal it is not possible that anything else be syllogized.

CHAPTER III.

For what one should use this exercise, and by which exercise one should use this or that.

But since exercise is both in inductive propositions and in syllogistic or universal ones, the exercise of inductive propositions must be used toward rude and inexperienced persons who judge according to sense; but the exercise of syllogistic or universal propositions must be used toward an educated respondent who judges according to intellect. And indeed one must try to accept propositions from syllogistic speeches or argumentations, which are propositions for this reason and are so called, because they can be posited for concluding other things, and these are universal. But from inductive particulars one must try to take likenesses and parables; for thus very many speeches are made: for in these and such things both inductive and also syllogistic speeches are exercitative, that is, for proper exercise