Sefer ha-Ikkarim ("Book of Principles") is a fifteenth century work by rabbi Joseph Albo, a student of Crescas. It is an eclectic, popular work, whose central task is the exposition of the principles of Judaism. [1]
Agreeing with Simeon ben Joseph of Lunel (i.e.: Duran), Albo held that there are three basic principles (ikkarim) that are necessary for the divine law to exist:
From these three principles, Albo posited that there are eight derivative principles (shorashim):
The denial of these principles, no less than the denial of the first three, makes one a heretic (kofer be-ikkar). It is understood in Albo's work that there are three kinds of law: natural law, conventional law, and divine law. Natural law is the same for all persons, times, and places; conventional law is ordered by a wise judge in accord with reason; divine law is given by God through a prophet.