The tilted carts at which he worked in Vian's shop, those carts which he had lovingly cherished, now seemed unworthy of his affections.

He began to attend the local drawing-school, where he formed a connection with a youngster who had left college, and who lent him an old treatise on geometry.

He plunged into this study without a guide, racking his brains for weeks together in order to grasp the simplest problem in the world.

In this matter he gradually became one of those learned workmen who can hardly sign their name and yet talk about algebra as though it were an intimate friend.
Nothing unsettles the mind so much as this desultory kind of education, which reposes on no firm basis.

Most frequently such scraps of knowledge convey an absolutely false idea of the highest truths, and render persons of limited intellect insufferably stupid.