This is a new contribution of Maimonides. All the Jewish writers before Halevi followed in their proofs of the existence of God the method designated by Maimonides as that of the Kalam. Judah Halevi criticised the Mutakallimun as well as the philosophers in the interest of a point of view all his own (pp. 176 ff., 182). Ibn Daud tacitly ignored the Kalam and based his proof of the existence of God upon the principles of motion as exhibited in the Aristotelian Physics, without, however, finding it necessary to assume even provisionally the eternity of motion and the world (p. 217 ff.). His proof of the incorporeality of God is, as we have seen (_ibid._), weak, just because he does not admit the eternity of motion, which alone implies infinity of power in God and hence incorporeality. Maimonides is the first who takes deliberate account of the Mutakallimun, gives an adequate outline of the essentials of their teaching and administers a crushing blow to their principles as well as their method. He then follows up his destructive criticism with a constructive method, in which he frankly admits that in order to establish the existence, unity and incorporeality of God--the three fundamental dogmas of Judaism--beyond the possibility of cavil, we must make common cause with the philosophers even though it be only for a moment, until they have done our work for us, and then we may fairly turn on our benefactors and taking advantage of their weakness, strike them down, and upon their lifeless arguments for the eternity of the world establish our own more plausible theory of creation. The attitude of Maimonides is in brief this. If we were certain of creation, we should not have to bother with the philosophers. Creation implies the existence of God. But the question cannot be strictly demonstrated either way. Hence let us prove the existence of God on the least promising hypothesis, namely, that of eternity, and we are quite secure against all possible criticism. Of the twelve propositions of the Mutakallimun enumerated by Maimonides as the basis of their doctrine of God, we shall select a few of the most important.[264] 1. _The Theory of Atoms._ The entire universe is made up of indivisible bodies having no magnitude. Their combination produces magnitude and corporeality. They are all alike. Genesis and dissolution means simply the combination or rather aggregation of atoms and their separation. These atoms are not eternal, as Epicurus believed them to be, but created. 2. This atomic theory they extend from magnitude to time. Time also according to them is composed of moments or atomic units of time. Neither magnitude, nor matter, nor time is continuous or infinitely divisible.