But if the things which are set forth in these books deserved to be selected with such great eagerness and care as they were, then certainly, neither we ourselves nor others will repent of our industry.  But if we appear either rashly to have passed over some doctrine of some one worth noticing, or to have adopted it without sufficient elegance, in that case when we are taught better by some one, we will easily and cheerfully change our opinion.  For what is discreditable is, not the knowing little, but the persisting foolishly and long in what one does not understand, because the one thing is attributed to the common infirmity of man, but the other to the especial fault of the individual.

Wherefore we, without affirming anything positively, but making inquiry at the same time, will advance each position with some doubt, lest while we gain this trifling point of being supposed to have written this treatise with tolerable neatness, we should lose that which is of the greater importance, the credit, namely, of not adopting any idea rashly and arrogantly.  But this we shall endeavour to gain both at present and during the whole course of our life with great care, as far as our abilities will enable us to do so.  But at present, lest we should appear to be too prolix, we will speak of the other points which it seems desirable to insist on.

Therefore, while we were explaining the proper classification of this art, and its duties, and its object, and its subject matter, and its divisions, the first book contained an account of the different kinds of disputes, and inventions, and statements of cases, and decisions.  After that, the parts of a speech were described, and all necessary precepts for all of them were laid down.  So that we not only discussed other topics in that book with tolerable distinctness, we spoke at that same time in a more scattered manner of the topics of confirmation and reprehension; and at present we think it best to give certain topics for confirming and reprehending, suited to every class of causes.  And because it has been explained with some diligence in the former book, in what manner argumentations ought to be handled, in this book it will be sufficient to set forth the arguments which have been discovered for each kind of subject simply, and without any embellishment, so that, in this book, the arguments themselves may be found, and in the former, the proper method of polishing them.  So that the reader must refer the precepts which are now laid down, to the topics of confirmation and reprehension.

IV.  Every discussion, whether demonstrative, or deliberative, or judicial, must be conversant with some kind or other of statement of the case which has been explained in the former book; sometimes with one, sometimes with several.  And though this is the case, still as some things can be laid down in a general way respecting everything, there are also other rules and different methods separately laid down