In commenting upon the works of Hippocrates, Galen insists that in speaking of “something divine” in diseases Hippocrates could not have meant supernatural influence, which he never admits into medicine in other passages. Galen tries to explain away the expression as having reference to the effect of the surrounding air.[663] Thus while Galen might look upon nature or certain things in nature as a divine work, he would not admit any supernatural force in science or medicine, or anything bordering upon special providence. In the _De usu partium_ Galen states that he agrees with Moses that “the beginning of genesis in all things generated” was “from the demiurge,” but that he does not agree with him that anything is possible with God and that God can suddenly turn a stone into a man or make a horse or cow from ashes. “In this matter our opinion and that of Plato and of others among the Greeks who have written correctly concerning natural science differs from the view of Moses.” In Galen’s view God attempts nothing contrary to nature but of all possible natural courses invariably chooses the best. Thus Galen expresses his admiration at nature’s providence in keeping the eyebrows and eyelashes of the same length and not letting them grow long like the beard or hair, but this is because a harder cartilaginous flesh is provided for them to grow in, and the mere will of God would not keep hairs from growing in soft flesh. If God had not provided the cartilaginous substance for the eyelashes, “he would have been more careless, not merely than Moses but than a worthless general who builds a wall in a swamp.”[664] As between the views on God of Moses and Epicurus, Galen prefers to steer a middle course. [Sidenote: Galen’s experimental instinct.]