In this work, we present a new way of understanding psychology, which emerges as a result of relating it to the three principles of the theory of fashion of Gilles Lipovetsky: “the principle of the ephemeral,” “the principle of the marginal differentiation of individuals,” and “the principle of seduction.” We relate the first principle to the plurality of the diverse and changing “schools and systems” that have existed throughout the history of psychology. We apply the second to the figure of the psychologist, considered individually, revealing his or her leading role in the generation of the changing plurality of the systems. By means of the third principle, we point up that the diverse psychologies are forms of seduction. We conclude by stating that psychology has the form of fashion and we analyze how this form can help us to better understand it.

This article analyses various transformations that took place within the Spanish colonial trade before the implementation of the 1778 free trade regulations. Firstly it shows the changes in the pattern of trade caused by the adoption in 1739 of the system of register ships (single «registered» ships), which resulted in the cancellation of the traditional system of fleets. Secondly it examines the role of transatlantic mail in shaping a new, increasingly retail-oriented pattern of trade. Finally, it deals with the evolution of the flow of commercial information crossing the Atlantic, stressing the growing impact of fashion. The primary sources used are mainly letters belonging to Spanish merchants that were confiscated by the British during the eighteenth-century wars.