His Kabbalistic system may be gathered from the following analysis of his Rejoinder to R. Solomon ben Abraham ben Adereth, who attacked his doctrines and Messianic as well as prophetic pretensions. “There are,” says Abulafia, “four sources of knowledge—I, The five senses, or experimental maxims; II, Abstract numbers or à priori maxims; III, The generally acknowledged maxims, or consensus communis; and IV, Transmitted doctrines or traditional maxims. The Kabbalistic tradition, which goes back to Moses, is divisible into two parts, the first of which is superior to the second in value, but subordinate to it in the order of study. The first part is occupied with the knowledge of the Deity, obtained by means of the doctrine of the Sephiroth, as propounded in the Book Jetzira. The followers of this part are related to those philosophers who strive to know God from his works, and the Deity stands before them objectively as a light beaming into their understanding. These, moreover, give to the Sephiroth sundry names to serve as signs for recognition; and some of this class differ but little from Christians, inasmuch as they substitute a decade for the triad, which they identify with God, and which they learned in the school of Isaac the Blind. “The second and more important part strives to know God by means of the twenty-two letters of the alphabet, from which, together with the vowel points and accents, those sundry divine names are combined, which elevate the Kabbalists to the degree of prophecy, drawing out their spirit, and causing it to be united with God and to become one with the Deity. This is gradually effected in the following manner. The ten Sephiroth sublimate gradually to the upper Sephira, called thought, crown, or primordial air, which is the root of all the other Sephiroth, and reposes in the creative En Soph. In the same manner all the numerals are to be traced back to one, and all the trees, together with their roots and branches, are converted into their original earth as soon as they are thrown into the fire. To the ten Sephiroth, consisting of upper, middle and lower, correspond the letters of the alphabet, which are divided into three rows of ten letters each, the final letters inclusive, beginning and ending with Aleph; as well as the human body, with its head, the two arms, loins, testicles, liver, heart, brain, all of which unite into a higher unity and become one in the active νοῦς, which in its turn again unites itself with God, as the unity to which everything must return.