Inasmuch as no rules are laid down for those who argue for the sake of training and of examination for the aim of those engaged in teaching or learning is quite different from that of those engaged in a competition; as is the latter from that of those who discuss things together in the spirit of inquiry; for a learner should always state what he thinks (for no one tries to teach what is false); whereas in a competition the business of the questioner is to appear by all means to produce an effect upon the other, while that of the answerer is to appear unaffected by him; on the other hand, in dialectical meetings held in the spirit not of a competition but of an examination and inquiry, there are as yet no articulated rules about what the answerer should aim at, and what kind of things he should and should not grant for the correct or incorrect defence of his position