The Latin translation of Aristotle's books on animals, which was carried out during the middle ages, lead to the dissemination of new theories in the field of biology and zoology in the western culture. From the second half of the 13th century, this group of books contributed to the development of a new medical practice based on the recovery of classical authorities and natural philosophy. On different occasions, Arnau de Vilanova (c. 1240-1311)--one of the most preeminent physicians of the Latin middle ages--used the books on animals to describe biological and physiological processes, and also to formulate a new medical discipline within the framework of discussions between natural philosophy and medicine in Montpellier; this took place at the end of the 13th century and early 14h century.