believe from things less credible. If, then, we ought not to make the problem more difficult, (that axiom) must be laid down, but if it is necessary) to syllogize through things more known, it must not be laid down; or must it not be posited by the learner, except it be more known, but must be laid down by him who exercises himself, if it only appear true? so that it is evident that the querist, and the teacher ought, not similarly to require a thing to be laid down.
Chapter 4
Almost sufficient then, has been said as to how it is necessary to interrogate and arrange, but about reply, we must first determine what is the employment of him who answers rightly, as also of him who rightly interrogates. Now, it is the duty of the interrogator, so to induce the argument, as to make the respondent assert the most incredible things, of those which are necessary through the thesis, but of the respondent (to take care) that the impossible, or the paradoxical, do not seem to result through him, but through the thesis, since perhaps it is another fault, to place that first which ought not to be so, and not to keep what is laid down, in a proper manner.
Chapter 5
Since the several particulars are indefinite, (which should be observed) by those who dispute for the sake of exercise and experiment—(for the same objects are not (proposed) to the teacher or the learner, and to those who contend, nor to both these, and to those who practise with each other for the sake of inquiry; for to the learner always, things which appear (true) are to be laid down,
