（4）Again, as we said before, every formed disposition of the soul realizes its full naturei.e., is actively exercised when fully developed, cf. 2.8. in relation to and in dealing with that class of objects by which it is its nature to be corrupted or improved. But men are corrupted through pleasures and pains, that is, either by pursuing and avoiding the wrong pleasures and pains, or by pursuing and avoiding them at the wrong time, or in the wrong manner, or in one of the other wrong ways under which errors of conduct can be logically classified. This is why some thinkersThe reference is probably to Speusippus, although in the extant remains of Greek philosophy apathy, or freedom from passions or emotions, first appears as an ethical ideal of the Stoics. define the virtues as states of impassivity or tranquillity, though they make a mistake in using these terms absolutely, without adding ‘in the right （or wrong） manner’ and ‘at the right （or wrong） time’ and the other qualifications.