But in discussing Judaism it is always imperative to discard all _a priori_ probabilities. Judaism is the great upsetter of the probable. Analyse a tendency of Judaism and predict its logical consequences, and then look in Judaism for consequences quite other than these. Over and over again things are not what they ought to be. The sacrificial system should have destroyed spirituality; in fact, it produced the Psalter, 'the hymnbook of the second Temple.' Pharisaism ought to have led to externalism; in fact, it did not, for somehow excessive scrupulosity in rite and pietistic exercises went hand in hand with simple faith and religious inwardness. So, too, the expression of ethics and religion as Law ought to have suppressed individuality; in fact, it sometimes gave an impulse to each individual to try to impose his own concepts, norms, and acts as a Law upon the rest. Each thought very much for himself, and desired that others should think likewise. We have already seen that in matters of dogma there never was any corporate action at all; in ancient times, as now, it is not possible to pronounce definitely on the dogmatic teachings of Judaism. Though there has been and is a certain consensus of opinion on many matters, yet neither in practice nor in beliefs have the local, the temporal, the personal elements ever been negligible. In order to expound or define a tenet or rite of Judaism it is mostly necessary to go into questions of time and place and person. Perhaps, then, we ought to be prepared to find, as in point of fact we do find, within the main body of Judaism, and not merely as a freak of occasional eccentrics, distinct mystical tendencies. These tendencies have often been active well inside the sphere of the Law. Mysticism was, as we shall see, sometimes a revolt against Law; but it was often, in Judaism as in the Roman Catholic Church, the outcome of a sincere and even passionate devotion to authority. Jewish mysticism, in particular, starts as an interpretation of the Scriptures. Certain truths were arrived at by man either intuitively or rationally, and these were harmonised with the Bible by a process of lifting the veil from the text, and thus penetrating to the true meaning hidden beneath the letter. Allegorical and esoteric exegesis always had this aim: to find written what had been otherwise found. Honour was thus done to the Scriptures, though the latter were somewhat cavalierly treated in the process; Philo's doctrine (at the beginning of the Christian era) and the great canonical book of the mediaeval Cabbala, the Zohar (beginning of the fourteenth century), were alike in this, they were largely commentaries on the Pentateuch. Maimonides in the twelfth century followed the same method, and only differed from these in the nature of his deductions from Scripture. This prince of rationalists agreed with the mystics in adopting an esoteric exegesis. But he read Aristotle into the text, while the mystics read Plato into it.