But, it has been said, and it needed no great cleverness to say it—­What a strange way is this of reasoning!  Here is a man who first proves that God is, by means of his reason; and then proves that his reason is good because God is.  His reason demonstrates God to him, and God demonstrates his reason to him:  it is an argument of which any schoolboy can at once see the fallacy; it is manifestly a vicious circle.  This has been said again and again by persons who have neglected a sufficiently simple consideration.  The error is apparently a gross one; is it not likely that the argument has been misunderstood?  Ought we not to look very closely at it, before declaring that one of the most lucid minds that have ever appeared in the world left at the basis of his doctrine a fault of logic which any schoolboy can discover?  Self-sufficient levity of spirit is not the best means of penetrating the thought of leading minds; and it very often happens to us to fail of understanding because we have failed in respect.

Let us examine with serious attention, not the very words of Descartes, as an historian might do, but the course of thought of which Descartes is one of the most illustrious representatives.

To recognize in the reason traces of God, and to show that in faith in God consists the only warrant of the reason, is not to argue in a vicious circle, because, in this way of proceeding, what we are employed in is not reasoning, but analysis; we are establishing a fact in order to ascertain what that fact implies and supposes.  This fact is the natural faith which man has in his own reason, when his reason reveals to him the immediate light of evidence, or the mediate light of certainty.  Now, when man confides in his reason, it is not in his individual reason that he confides, for he has no doubt that what is evident for him is so also for others.  If, tossed by a tempest, he were thrown upon an island of savages, he would not think that those savages, when they came to reflect, would be able to discover that the axioms of our geometry are false, or to make elements of logic which would contradict our own.  We believe in a general reason, everywhere and always the same, and in which the reason of each individual participates.  We believe therefore that there is a principle of truth which exists in itself, a reason which is eternal and everywhere present; in other words, we believe in God considered as the source of the universal intelligence.  To believe in one’s reason, is to believe in God, in this sense:  the fact of the confidence which we place in our own faculty of thought, supposes a concealed faith in eternal truth.  This is the analysis of which I was speaking.  It is a circle if you please, but it is a circle of light, outside of which there is, as we shall see by and by, nothing but darkness and hard contradictions.