Proudhon states that his system merely involves the universal adoption of exchange notes.[675] The Exchange Bank would merely append the manager’s signature against the particular commodity discounted. But the issue of bank-notes at the present time involves nothing more than this. Instead of the bill of exchange which it now buys, and which enjoys only a limited circulation because the signatories have only a very limited credit, it is proposed that the Bank of France should substitute a note bearing its own signature, which is universally known and testifies to an illimitable amount of credit. In what respects, then, does Proudhon’s circulating medium differ from a bank-note? It differs simply in the fact that the signature of the Bank of France involves a promise of reimbursement in metallic money, a commodity universally accepted and demanded, while Proudhon’s Exchange Bank enters into no such definite agreement, but merely undertakes to accept it in lieu of payment. Theoretically, perhaps, the difference may appear insignificant, since the signatures are the only guarantee of the solvency of the notes of the Bank of France and the Exchange Bank alike. But in practice it is enormous. The certainty that the note can be exchanged for money gives it a wide currency and makes it acceptable to many people who rely implicitly upon their confidence in the bank. They need give no thought to the question of its solvency. A mere circulating medium, on the other hand, in addition to transferring a claim to certain goods belonging to clients of the bank, involves a certain amount of confidence in the solvency of those clients—a confidence not always easily justified. A note of this kind will only circulate among the bank’s _clientèle_. It will never reach the general public as the bank-note actually does. The clients themselves will keep their engagements just so long as the bank continues to discount goods that have actually been delivered and never refuses payment when it falls due. Failing this, the exchange notes, instead of regularly returning to the bank, will remain in circulation. A slight crisis or a little tension, and many of the clients will become insolvent. The total nominal value of the exchange notes will quickly surpass the actual value of the goods which they represent. There will be a rapid depreciation, and clients even will refuse to take them. It is just possible to conceive of the circulation of such exchange notes, but the area of circulation will be a very limited one, and it will be utterly impossible if all the clients are not perfectly solvent. Let us, however, suppose that the practical difficulties have been overcome, and that the exchange notes are already in circulation. Interest will not disappear even then, and herein lies the essential weakness of the system.