§ i. What amount of argument, Sossius Senecio,…

illuminates and cleanses the soul), cannot consider it unreasonable to think that the change will be perceived, as people who come up out of some ravine can take note of the progress they make upwards. Look at the case from the following point of view first. Just as mariners sailing with full sail over the gaping⁴ ocean measure the course they have made by the time they have taken and the force of the wind, and compute their progress accordingly, so anyone can compute his progress in philosophy by his continuous and unceasing course, by his not making many halts on the road, and then again advancing by leaps and bounds, but by his quiet and even and steady march forward guided by reason. For the words of the poet, "If to a little you keep adding a little, and do so frequently, it will soon be a lot,"⁵ are not only true of the increase of money, but are universally applicable, and especially to increase in virtue, since reason invokes to her aid the enormous force of habit. On the other hand the inconsistencies and dulnesses of some philosophers not only check advance, as it were, on the road, but even break up the journey altogether, since vice always attacks at its leisure and forces back whatever yields to it.⁶ The mathematicians tell us that planets, after completing their course, become stationary; but in philosophy there is no such intermission or stationary position from the cessation of progress, for its nature is ever to be moving and, as it were, to be weighed in the scales, sometimes being overweighted by the good preponderating, sometimes by the bad. If, therefore, imitating the oracle given to the Amphictyones by the god, "to fight against the people of Cirrha every day and every night,"⁷ you are conscious that night and day you ever maintain a fierce fight against vice, not often relaxing your vigilance, or long off your guard, or receiving as heralds to treat of peace⁸ the pleasures, or idleness, or stress of business, you