Thus far we have heard William cite authorities rather than spurn them as Adelard did. He could, however, be independent enough on occasion. He went so far as to reject the Scriptural account of waters above the firmament, if that word were taken in its ordinary astronomical sense, as naturally impossible; he explained away the passage in _Genesis_ by interpreting the firmament to mean the air, and the waters above it, the clouds.[148] Like Adelard, too, he several times feels it essential to justify his views against the possible criticism of an obscurantist religious party. Discussing the Trinity, he insists that if anyone finds something in his book which is not found elsewhere, it should not on that account be stigmatized as heresy but only if it can be shown to be against the Faith.[149] Thus he confirms Adelard’s complaint that the present generation is prejudiced against any modern discoveries. William, by the way, also employs the word “modern.” Again, in affirming the physical impossibility of reconciling the elements fire and earth, he notes that someone may object that God could find a way. To this he replies that “we do not place a limit upon divine power, but we do say that of existing things none can do it, nor in the nature of things can there be anything that would suffice.”[150] In a third passage his indignation is fanned to a white heat by those who say, “We do not know how this is, but we know that God can do it.” “You poor fools,” he retorts, “God can make a cow out of a tree, but has He ever done so? Therefore show some reason why a thing is so, or cease to hold that it is so.”[151] Elsewhere he yet further dilates upon the unreasonableness of the opponents of natural science, who are loath to have explained even the natural facts given in the Bible but prefer to accept them blindly, and who, “since they themselves are unacquainted with the forces of nature, in order that they may have all men as companions in their ignorance, wish them to investigate nothing but to believe like rustics. We, on the contrary,” continues William, “think that a reason should be sought in every case, if one can be found.”[152] Thus he vigorously echoes Adelard’s exhortation to give and take reason, and his retort to the nephew’s suggestion that the growth of plants from earth can be explained only as a divine miracle. [Sidenote: Letter of William of St. Thierry to St. Bernard.]