"To live without doing some good is a great evil as well in the political as in the moral world; and hence every useless citizen should be regarded as a pernicious person. Tell me then, illustrious philosophers, of whom we learn theratios in which attraction acts in vacuo; and in the revolution of the planets, the relations of spaces traversed in equal times; by whom we are taught what curves have conjugate points, points of inflexion, and cusps; how the soul and body correspond, like two clocks, without actual communication; what planets may be inhabited; and what insects reproduce in an extraordinary manner. Answer me, I say, you from whom we receive all this sublime information, whether we should have been less numerous, worse governed, less formidable, less flourishing, or more perverse, supposing you had taught us none of all these fine things."