We are wont to allure children by rewards, that they may cheerfully learn what we force them to study even though they are unwilling.

For our fallen nature does not tend to virtue with the same enthusiasm with which it rushes into vice.

Horace has expressed this for us in a brief verse of the Ars Poetica, where he says: All poets sing to profit or delight.
And he has plainly intimated the same thing in another verse of the same book, where he says: He hits the mark, who mingles joy with use.
How many students of Euclid have been repelled by the Pons Asinorum, as by a lofty and precipitous rock, which no help of ladders could enable them to scale! THIS IS A HARD SAYING, they exclaim, AND WHO CAN RECEIVE IT.

The child of inconstancy, who ended by wishing to be transformed into an ass, would perhaps never have given up the study of philosophy, if he had met him in friendly guise veiled under the cloak of pleasure; but anon, astonished by Crato's chair and struck dumb by his endless questions, as by a sudden thunderbolt, he saw no refuge but in flight.
So much we have alleged in defence of the poets; and now we proceed to show that those who study them with proper intent are not to be condemned in regard to them.

For our ignorance of one single word prevents the understanding of a whole long sentence, as was assumed in the previous chapter.