 In passing I should like to note here that the more recent Peripatetics have, as I think, misunderstood the demonstration by which the Ancients tried to prove God’s existence. For as I find it in a certain Jew, called Rab Chasdai, it runs as follows: if there is an infinite regress of causes, then all things that are will also have been caused; but it does not pertain to anything which has been caused, to exist necessarily by the force of its own nature; therefore, there is nothing in Nature to whose essence it pertains to exist necessarily; but the latter is absurd; therefore, the former is also. Hence the force of this argument does not lie in the impossibility of there being an actual infinite or an infinite regress of causes, but only in the supposition that things which do not exist necessarily by their own nature are not determined to exist by a thing which does necessarily exist by its own nature. [Ep. 12| IV/61/15–62/10; italics added]