the quantitative theory of money and represents the most complete Spanish model of mercantilism. He pointed out the weaknesses of the Spanish economy and especially the penury and the invasion of foreign products, and denounced that the kingdom had become a debtor of the enemy powers. His solution was to propose a severe protectionism of mercantile discipline supervised by the Inquisition. In addition, it was necessary to promote the industry as Jean-Baptiste Colbert would later propose in France. His work, unlike that of other arbitrators, enjoyed great prestige and influence and was taken over by the great enlightened of the eighteenth century, when it was reissued. Pedro Fernández de Navarrete The Riojan Pedro Fernández de Navarrete (1564 - 1632), canon of Santiago, Seneca translator humanist and royal adviser, was inspired by Cellorigo and Moncada to write his Conservation of Monarchies, a work of mercantilist bias that advocated the control of imports and the promotion of exports, although it did not fall into the trap of bullionism, because it understood that the overabundance of money is pernicious if there are no goods that can be acquired. He proposed the development of productive investments and criticized the luxury and contempt for industrial and manual trades by the nobility and nobility of Spain of his time. Luis Valle de la Cerda Luis Valle de la Cerda wrote in 1600 Performance of the Patrímonto of His Majesty and of the kingdoms, without damage of the King and vassals, and with rest and relief of all, through the public Treasury and Montes de Piedad. His work was highly valued by the Cortes, which supported this initiative, and reissued it in 1618. The Montes de Piedad was an idea in a way similar to the Granados that already worked, as credit entities of municipal foundation and grain stores that lent to the farmers. The foundation of the first Monte de Piedad was made in Madrid by Father Piquer in the early eighteenth century, and in the mid-nineteenth century was associated with the Savings Bank (founded by the Marquis of Pontejos). These financial institutions already correspond to a protocapitalist world, in which other important institutions also functioned, such as the Five Greater Guilds of Madrid or the Bank of San Carlos, antecedent of the Bank of Spain. Juan de Castro Juan de Castro was a priest with ties to the Genoese banking community. His critique of the