Keep this thought in readiness, when you lose anything external, what you acquire in place of it; and if it be worth more, never say, “I have had a loss”; neither if you have got a horse in place of an ass, or an ox in place of a sheep, nor a good action in place of a bit of money, nor in place of idle talk such tranquillity as befits a man, nor in place of lewd talk if you have acquired modesty. If you remember this, you will always maintain your character such as it ought to be. But if you do not, consider that the times of opportunity are perishing, and that whatever pains you take about yourself, you are going to waste them all and overturn them. And it needs only a few things for the loss and overturning of all, namely a small deviation from reason. For the steerer of a ship to upset it, he has no need of the same means as he has need of for saving it: but if he turns it a little to the wind, it is lost; and if he does not do this purposely, but has been neglecting his duty a little, the ship is lost. Something of the kind happens in this case also: if you only fall to nodding a little, all that you have up to this time collected is gone. Attend therefore to the appearances of things, and watch over them; for that which you have to preserve is no small matter, but it is modesty and fidelity and constancy, freedom from the affects, a state of mind undisturbe............