At last, the strain became too great and at the court of Nizam al-Mulk he touched for two months the depths of absolute scepticism. He doubted the evidence of the senses; he could see plainly that they often deceived. No eye could perceive the movement of a shadow, but still the shadow moved; a gold piece would cover any star, but a star was a world larger than the earth. He doubted even the primary ideas of the mind. Is ten more than three? Can a thing be and not be? Perhaps; he could not tell. His senses deceived him, why not his mind? May there not be something behind the mind and transcending it, which would show the falsity of its convictions even as the mind showed the falsity of the information given by the senses? May not the dreams of the Sufis be true, and their revelations in ecstasy the only real guides? When we awake in death, may it not be into a true but different existence? All this—perhaps. And so he wandered for two months. He saw clearly that no reasoning could help him here; he had no ideas on which he could depend, from which he could begin. But the mercy of God is great; He sends His light to whom He wills, a light that flows in, and is given by no reasoning. By it al-Ghazzali was saved; he regained the power to think, and the task which he now set before him was to use this power to guide himself to truth. [Sidenote: THE SEEKERS OF HIS TIME] When he looked around, he saw that those who gave themselves to the search for truth might be divided into four groups. There were the scholastic theologians, who were much like the theologians of all times and faiths. Second, there were the Ta‘limites, who held that to reach truth one must have an infallible living teacher, and that there was such a teacher. Third, there were the followers of philosophy, basing on logical and rational proofs. Fourth, there were the Sufis, who held that they, the chosen of God, could reach knowledge of Him directly in ecstasy. With all these he had, of course, been acquainted to a greater or less degree; but now he settled down to examine them one by one, and find which would lead him to a certainty to which he could hold, whatever might come. He felt that he could not go back to the unconscious faith of his childhood; _that_ nothing could restore. All his mental being must be made over before he could find rest. He began with scholastic theology, but found no help there. Grant the theologians their premises and they could argue; deny them and there was no common ground on which to meet. Their science had been founded by al-Ash‘ari to meet the Mu‘tazilites; it had done that victoriously, but could do no more. They could hold the faith against heretics, expose their inconsistencies; against the sceptic they availed nothing. It is true that they had attempted to go further back and meet the students of philosophy on their own ground; to deal with substances and attributes and first principles generally; but their efforts had been fruitless.