What we have to do in estimating the probable truth of our immortality, as shown by the science of natural religion, is to give the same force to moral evidence in this particular department of belief, that we give to the moral evidence which convinces us of many things of which we have no direct proof, or of which the direct proof lies in evidence of another kind. "He knew as much about it," said Voltaire, "as has been known in all ages--that is to say, very little indeed." This, like many of the witticisms of Voltaire, pressed into the service of an argument against the value of natural religion at the present day when studied by mature and disciplined minds, is quite out of place. What human reason has done in the course of three thousand years is not to be put on a par with the speculations of intelligent children or half-civilized men; and although some of the riddles which perplexed Eliphaz and Zophar have not had a perfectly satisfactory solution, it is quite wide from the truth to assert that there has been no approximation to a satisfactory solution, or that some of the riddles have not ceased to be the riddles which they were three thousand years ago. In that period there has been an accumulation of evidence concerning the phenomena of Nature, and the phenomena of mind, vast beyond comparison when placed in contrast with what was known in the tents of the Idumean emirs, and the importance of this accumulation of evidence is proved by the fact that theories have been built upon it which undertake to explain it by hypotheses that were never heard of before, and which may possibly leave the "riddles" in a far less satisfactory state than they were in the time of Job. On the other hand, while the companions of Job may have been unable to suggest to him any solution of the problems of life, it does not at all follow that we are as helpless as they were, even if we avail ourselves of nothing but what the science of natural theology can now teach us.[11]