Martin de Azpilcueta, Comentario resolutorio de cambios (Salamanca, 1556)
A canon lawyer set out to explain one decretal on usury and, on printed page 85, explained inflation instead: goods and the labour of men fetched far less in Spain before the Indies covered it with gold and silver, the cause being that money is worth more where it is scarce. The quantity theory of money reaches print here, in a commentary on moneylending, twelve years before Bodin.
Why this wins its question: Azpilcueta is cited in economics as the first formulation of the quantity theory of money and almost never quoted, so the reader is asked to take the attribution on trust from a secondary tradition that mostly cites itself. This object opens the 1556 sheets and prints the sentence, the rule drawn from it, the coin premiums and the Portuguese teston observations offered as evidence, and the page 86 answer that separates the unchanged nominal denomination from the changed quantity of goods, ceteris paribus clause included. It also does what the attribution literature does not: it records that the doctrine appears inside a commentary on a usury decretal rather than in a treatise on money, that a named contemporary held the other view, that the author had once preferred that view himself, and that nothing on these pages amounts to a quantitative theory in the modern sense. The date and the wording are firm; the priority is left as what the sheets can carry.
Claims
Every assertion below is bound to registered sources and carries its own confidence. Weight them; do not treat the page as uniformly authoritative.
The copy read here carries no title page that the page-image endpoint would serve, but it carries its colophon, and the colophon is explicit: "Acabose de imprimir la presente obra en la muy noble ciudad de Salamanca, en casa de Andrea de Porto narijs. Impressor de la. S. C. M. A doze de Agosto. M. D. LVI." The sheets read here were therefore finished at Salamanca on 12 August 1556.
The work is not an economic treatise and does not present itself as one. It opens at printed page 48 under the drop-title "Comentario resolutorio de Cambios, sobre el principio del capitulo final de vsuris", and its declared starting point is a decretal quoted in Latin and then rendered into Castilian: whoever lends a fixed sum to a man who sails or goes to the fairs, taking the risk on himself and expecting to receive something beyond the principal, is to be judged a usurer. Everything that follows is commentary on that sentence.
The monetary argument arrives on printed page 85 as evidence for a point about exchange. In Spain, the text reads, at the time when there was less money, "por mucho menos se dauan las cosas vendibles, las manos y trabajos de los hombres, que despues, que las Indias descubiertas la cubrieron de oro y plata". The cause is then stated as a rule: "el dinero vale mas donde, y quando ay falta del, que donde, y quando ay abundancia". American bullion is named on the page as the thing that changed the price level.
The rule is argued from observation, not asserted. The same page prices the scarcity of gold coin - some were giving twenty-three, and even twenty-four and twenty-five reals for a doblon whose legal price in the kingdom was no more than twenty-two - and reports from Portugal that eleven ducados and a half, and even two more in silver, were being given for one of ten, and that a teston worth no more than a hundred had fetched a hundred and six in cetis when cetis were abundant and only ninety-four when they became scarce. The inference drawn is that a general scarcity of money raises the whole of it.
Printed page 86 states the mechanism with a precision that is easy to miss under the sixteenth-century spelling. Against the objection that scarcity does not make a ducado worth more reals, nor a real more quartos, nor quartos more maravedis, the answer given is that this is true and beside the point: "todo el dinero vale mas", because more saleable things are then found for a given sum of money than before. The clause that closes the sentence, "si lo al es ygual", is a statement of the condition that all else be equal.
The author records that he had held the other view. Page 86 introduces the contrary position of "el Doctor Medina" with the parenthesis "que algu dia nos parecio mejor", and page 85 opens the objections against his own opinion with the admission that they were once such that "algun dia nos parecio ella vana". The doctrine is printed together with the arguments against it and with a note of the moment its author changed his mind.
What the pages do not contain matters for how strongly the claim of priority can be pressed. There is no series of prices, no measure of the quantity of bullion arriving, and no attempt to relate the two; the Portuguese and Castilian observations are anecdotes recruited to settle a question about the licitness of exchange dealings. The text establishes that the relation between the quantity of money and the price of goods was stated in print in 1556, and that American silver was named as its cause. It does not establish a quantitative theory in the later sense, and this object claims none.
One further caution about priority, stated because the object would be weaker without it. The pages read here place the argument in a dispute already under way, with a named opponent and cited authorities on both sides; that is evidence of a scholastic conversation about money in which several people were working, not of a single discoverer. The firm claim available from the sheets is the date and the content, not the originality.