Since I have begun to make my definitions without a too strict adherence to the letter, a man may be called "happy" who, thanks to reason, has ceased either to hope or to fear: but rocks also feel neither fear nor sadness, nor do cattle, yet no one would call those things happy which cannot comprehend what happiness is. With them you may class men whose dull nature and want of self-knowledge reduces them to the level of cattle, mere animals: there is no difference between the one and the other, because the latter have no reason, while the former have only a corrupted form of it, crooked and cunning to their own hurt. For no one can be styled happy who is beyond the influence of truth: and consequently a happy life is unchangeable, and is founded upon a true and trustworthy discernment; for the mind is uncontaminated and freed from all evils only when it is able to escape not merely from wounds but also from scratches, when it will always be able to maintain the position which it has taken up, and defend it even against the angry assaults of Fortune: for with regard to sensual pleasures, though they were to surround one on every side, and use every means of assault, trying to win over the mind by caresses and making trial of every conceivable stratagem to attract either our entire selves or our separate parts, yet what mortal that retains any traces of human origin would wish to be tickled day and night, and, neglecting his mind, to devote himself to bodily enjoyments?