=163.= Closely connected with the theory of the syllogism is the enticing subject of the ‘resolution of fallacies’ (σοφισμάτων λύσις), which the Megarians had brought within the range of philosophy. To this subject the Stoics gave much attention[117]. The most famous fallacy is that of the ‘heap’ (σωρίτης, _acervus_); ‘if two are few, so are three; if three, then four; and so forth.’ In this Chrysippus took a special interest[118]; his reply was to keep still[119]. Another is the ‘liar’ (ψευδόμενος, _mentiens_); ‘when a man says “I lie,” does he lie or not? if he lies, he speaks the truth; if he speaks the truth, he lies[120].’ On this subject Chrysippus wrote a treatise, which Epictetus thought not worth reading[121]. Seneca gives us examples of other fallacies, which also are verbal quibbles[122]. Of an altogether different kind are those problems in which the question of determinism as opposed to moral choice is involved. Such is the ‘reaper,’ which maintains ‘either you will reap or you will not reap; it is not correct to say “perhaps you will reap.”’ Such again is the ‘master-argument’ of Diodorus the Megarian, directly aimed against every moral philosophy[123]. These difficulties we shall discuss later as touching the supreme problems which are presented to the human reason[124]. [Sidenote: Definition.] =164.= The scientific study of syllogisms and fallacies promises at first sight to be a guide to truth and a way of escape from error, but experience shews it nevertheless to be barren. It has however an advantage in securing a careful statement of teaching, and for this purpose was much used by Zeno and Chrysippus. The later members of the school realized that this advantage could be more simply gained by the practice of careful definition (ὅρος, _definitio_). Antipater thus defined definition itself: ‘definition is an expression which elaborates in detail without falling short or going too far[125].’ He and all other Stoics of his time gave numerous definitions of the most important terms used in the system, such as God, fate, providence, the supreme good, virtue, and so forth; and these are of great value in giving precision to their doctrine. [Sidenote: Style.]