f " 'Semellan argentadas'. La razón de los astros en el Libro de Alexandre"

In this paper one of the astronomical passages in the Libro de Alexandre is analysed: that in which the learned Aristander explains the eclipse of the moon. It is of particular interest to examine the way in which this erudite character demonstrates his ideas, because the anonymous poet and scholar remodels ancient ideas for the public of his time and thus they become perfectly suitable to the most modern cultural context in the western hemisphere in the twelfth and thirteenth centuries. This paper will try to show the roots from which spring the wish for greater scientific knowledge in the author of the Alexandre, a logical encyclopaedist as well as a poet.