This was four years before the appearance of Adam Smith's "Wealth of Nations." The Marquis de Mirabeau and others of his school had begun to write; but their notions of political economy were still unfamiliar to the public. M. de Chastellux may therefore be regarded as one of the first supporters of that doctrine of human perfectibility which lies at the bottom of all the prevailing opinions of the eighteenth century. To this he added another theory, that the only end of government ought to be "the greatest happiness of the greatest possible number." Nearly one hundred years ago, therefore, he discovered and developed the principle which is now one of the most popular epitomes of social science. His style is good, {183} but neither very concise nor very brilliant. It is now and then obscure, sometimes digressive, sometimes declamatory; but for the most part clear, lively, and abounding in those happy touches which show the writer to be a man of the world as well as an author. It is said that the immediate occasion of his writing the book was a conversation with Mably, the author of "Observations on the History of France," who maintained that the world was constantly degenerating, and that the men of to-day were not half so good as their grandfathers. The young philosopher, his head full of the new ideas, resolved to demonstrate the superiority of the present over the past. The first edition of his work appeared in 1772, two years before the death of Louis XV. It was printed anonymously in Holland. Everywhere it was read with avidity, abroad as well as in France. It was translated into English, German, and Italian. Voltaire read it at Ferney, and was so much struck by it that he covered his copy with marginal notes--not always of approbation--which were reproduced in a new edition of the work by the author's son, in 1822.