The Journal tenu par Isaac Beeckman de 1604 à 1634 has been studied in the history of the seventeenth-century scientific revolution following the theme of Isaac Beeckman's physical mathematical mechanistic view, his proto-molecular theory and his atomistic Lucretian influence. This article goes deeper into the medical ideas of the Journal: how Isaac Beeckman (1588-1637) settles the structure of living matter according to his intensive reading of Galen. It develops a different analysis from the traditionally triumphalist approach in the history of science, focused on the victory of Cartesian mechanism, particularly in the history of medicine taking up Galenism very briefly because of its obsolete physiology. The Galenic corpus inside Isaac Beeckman's Journal consists of the many commentaries of Galen which Beeckman has put down in writing since 1616 until 1627, after when the passages linked to Galen became fewer. Isaac Beeckman's study of Galenic medicine is analyzed according to three approaches: the teleological dimension of Galenism showing up the organic conception of human body corresponding to the divine Providence and consistent with Beeckman's Calvinist belief, the physiologic angle of Galenism, based on natural faculties, stressing the purely speculative aspect of Beeckman's commentaries, while the pathologic and therapeutic angle supports the Hippocratic humourism influence. ; Biography ; English Abstract ; Historical Article ; Journal Article ; Available here: http://www.gewina-studium.nl/index.php/studium/article/view/1508 ; SCOPUS: ar.j ; info:eu-repo/semantics/published