The new life was slow to take root; and when in the eleventh century the English monk Adelhard translated from the Arabic, which he had learned in his travels in Spain and Egypt, the Elements of Euclid, he found little welcome for it. Not till a century later did a fresh translation of Euclid from the Arabic, by Campanus, make its way in the schools. Algebra came from the same source, through a travelling merchant of Pisa, about the beginning of the thirteenth century. Thenceforth the infant sciences of physics held their ground, and from those beginnings became possible the lore of Roger Bacon. A genuine scientific spirit indeed was slow to grow; the ideals and ethics of religion had almost atrophied among Christians the instinct for simple truth; but the passion for astrology promoted astronomy, and the passion for gold promoted chemistry, all its practitioners hoping for the philosopher's stone, which should transmute lead into gold. Always it is from the Arabs that the impulse comes. Under the emperor Frederick II, who in his Sicilian seat gave free course to Saracen culture and thought, was first translated from the Arabic the Greek Ptolemy's great work on astronomy; and for Alphonso X of Castile, by Moorish means, were compiled new astronomical tables. From the Arabs, too, came trigonometry, which even for the Greeks had not been a separate science; and only in the fifteenth century did Müller of Königsberg ("Regiomontanus"), who perfected the decimal notation, first give it new developments. New philosophic thought came by the same paths. Between the philosophy of the Arab Averroës, with its Aristotelian basis and its lead to pantheism and materialism on the one hand, and the moral reaction set up by the Crusades on the other, the bases of Christian orthodoxy were shaken. The legend that Frederick II wrote a treatise entitled The Three Impostors, dealing with Moses, Jesus, and Mohammed, is a fable; there was probably no such book in the Middle Ages, for it would have meant death at the hands of the Inquisition to possess it; but the very phrase showed what men had become capable of thinking and saying.