Rabbi Isaac Abravanel (1437-1508) was the last medieval Jewish thinker systematically and extensively to deal with the question of the principles of Judaism. Indeed, he devoted an entire book to the subject, the Rosh Amanah. This book is ostensibly devoted to defending Maimonides’ thirteen principles in the face of the criticisms levelled against them by Crescas and Albo. Bot, paradoxically, and despite its avowed aim, the Rosh Amanah is best known for Abravanel's claim that Judaism has no principles of faith at all.

This was the situation which confronted Isaac Abravanel when he sat down to write his Rosh Amanah in 1494: the Jewish people had just suffered its greatest calamity since the destruction of the Second Temple and, in turning to their religious leaders in search of a clearly enunciated statement of what Judaism demanded of them, met with chaos. All of Abravanel's post-Expulsion literary activity was connected in one way or another with his attempt to encourage and console the shattered people. The Rosh Amanah fits into that pattern: in the place of conflicting and confusing opinions concerning the principles of Judaism, Abravanel sought to establish one system, that of Maimonides, as normative. In doing so he provided the most thorough analysis of Maimonides’ principles yet written.

Abravanel opens the book by quoting Maimonides’ statement of the principles in an otherwise unknown Hebrew translation. In the second chapter Abravanel briefly summarizes the dogmatic systems of Crescas and Albo. He claims that these scholars diverged from Maimonides’ account of the principles because of certain problems they found in his account. Abravanel saw fit, therefore, in chapters iii and iv to list these objections. We ought to note two points here. First, there is little doubt that Abravanel was wrong: Crescas and Albo did not reject Maimonides’ system because of specific problems they found with it, but because they defined the term ‘principle’ differently from Maimonides. Maimonides, as we have seen, used the term in a dogmatic sense, Crescas in an analytic sense, and Albo in a geometric sense. It is remarkable that Crescas and Albo were unaware of the way in which their usage of the term 'principle’ differed from that of Maimonides and from each other.