The _Discourse on the Arts and Sciences_, the earliest of the works reproduced in this volume, is not in itself of very great importance. Rousseau has given his opinion of it in the _Confessions_. "Full of warmth and force, it is wholly without logic or order; of all my works it is the weakest in argument and the least harmonious. But whatever gifts a man may be born with, he cannot learn the art of writing in a moment." This criticism is just. The first Discourse neither is, nor attempts to be, a reasoned or a balanced production. It is the speech of an advocate, wholly one-sided and arbitrary, but so obviously and naively one-sided, that it is difficult for us to believe in its entire seriousness. At the most, it is only a rather brilliant but flimsy rhetorical effort, a sophistical improvisation, but not a serious contribution to thought. Yet it is certain that this declamation made Rousseau's name, and established his position as a great writer in Parisian circles. D'Alembert even devoted the preface of the _Encyclopædia_ to a refutation. The plan of the first Discourse is essentially simple: it sets out from the badness, immorality and misery of modern nations, traces all these ills to the departure from a "natural" state, and then credits the progress of the arts and sciences with being the cause of that departure. In it, Rousseau is already in possession of his idea of "nature" as an ideal; but he has at present made no attempt to discriminate, in what is unnatural, between good and bad. He is merely using a single idea, putting it as strongly as he can, and neglecting all its limitations. The first Discourse is important not for any positive doctrine it contains, but as a key to the development of Rousseau's mind. Here we see him at the beginning of the long journey which was to lead on at last to the theory of the _Social Contract_.