"Is the interest of capital natural, just, and lawful, and as useful to the payer as to the receiver?" You answer, No; I answer, Yes. Then we differ entirely; but it is of the utmost importance to discover which of us is in the right, otherwise we shall incur the danger of making a false solution of the question, a matter of opinion. If the error is on my side, however, the evil would not be so great. It must be inferred that I know nothing about the true interests of the masses, or the march of human progress; and that all my arguments are but as so many grains of sand, by which the car of the revolution will certainly not be arrested. But if, on the contrary, MM. Proudhon and Thoré are deceiving themselves, it follows that they are leading the people astray--that they are showing them the evil where it does not exist; and thus giving a false direction to their ideas, to their antipathies, to their dislikes, and to their attacks. It follows that the misguided people are rushing into a horrible and absurd struggle, in which victory would be more fatal than defeat; since, according to this supposition, the result would be the realisation of universal evils, the destruction of every means of emancipation, the consummation of its own misery. This is just what M. Proudhon has acknowledged, with perfect good faith. "The foundation stone," he told me, "of my system is the _gratuitousness of credit_. If I am mistaken in this, Socialism is a vain dream." I add, it is a dream, in which the people are tearing themselves to pieces. Will it, therefore, be a cause for surprise, if, when they awake, they find themselves mangled and bleeding? Such a danger as this is enough to justify me fully, if, in the course of the discussion, I allow myself to be led into some trivialities and some prolixity. Capital and Interest. I address this treatise to the workmen of Paris, more especially to those who have enrolled themselves under the banner of Socialist democracy. I proceed to consider these two questions:-- 1st. Is it consistent with the nature of things, and with justice, that capital should produce interest? 2nd. Is it consistent with the nature of things, and with justice, that the interest of capital should be perpetual? The working men of Paris will certainly acknowledge that a more important subject could not be discussed. Since the world began, it has been allowed, at least in part, that capital ought to produce interest. But latterly it has been affirmed, that herein lies the very social error which is the cause of pauperism and inequality. It is, therefore, very essential to know now on what ground we stand.