If Naturalism is true, every finite thing or event must be (in principle) explicable in terms of the Total System. . . . But if Naturalism is to be accepted we have a right to demand that every single thing should be such that we see, in general, how it could be explained in terms of the Total System. If any one thing exists which is of such a kind that we see in advance the impossibility of ever giving it that kind of explanation, then Naturalism would be in ruins. (C. S. Lewis, Miracles)