The example of Littre is more touching still. I remember reading a sublime page in one of his works, in which the savant, after running through the _terra firma_ of positive knowledge, reaches its utmost limit, and, seating himself on the extremest promontory, sees himself surrounded by the mystery of the unknowable, as by an infinite ocean. He has neither barque, nor sails, nor compass wherewith to explore this boundless sea; nevertheless, he stands there gazing into it; he contemplates it; he meditates in presence of this vast unknown, and finally abandons himself to a movement of adoration and of confidence which renews his mental vigour and which fills his heart with peace. What is this, I ask, but a sudden outburst of religious feeling which positive science, so far from extinguishing, has only served to deepen and accentuate? And since we have here the religion of the unknowable, is it not evident that religion is not necessarily knowledge? I now come to a third explanation which, older than either of the others, will bring us nearer to the end at which we aim. "It is fear," says a Latin poet, "that engenders the gods." There is a sense in which this is true. It cannot be doubted that religion was at first awakened in the heart of man under the impress of the terror caused by the disordered and destructive forces of primitive Nature. Thrown naked and disarmed on the barely-cooled planet, walking tremblingly upon a soil that quaked beneath his tread, his would be a state of misery and distress which filled his heart with an infinite terror. But the explanation needs completing. In itself and of itself, fear is not religious; it paralyses, crushes, stuns. In order that it may become religiously fruitful, it is necessary that, from the outset, it should be mixed with an opposite sentiment, an impulse of hope; it is necessary that man, the prey of fear, should conceive, in some way or other, the possibility of surmounting it--that is to say that he should find above him some help, some succour, by which to confront the dangers which threaten him. Fear only gives birth to religion in man because it awakens hope and calls forth prayer--prayer that opens an issue to human distress. There is that amount of truth in the ancient hypothesis. It brings us near the source we are seeking, for it places us on the practical arena of life, and not in the theoretical region of science. The question man puts to himself in religion is always a question of salvation, and if he seems sometimes to be pursuing in it the enigma of the universe, it is only that he may solve the enigma of his life. And now we must press nearer to the problem. We must ascertain out of what fundamental contradiction the religious feeling arises. We may reach it by a mental analysis that every one can follow, and verify the more easily inasmuch as it is always in course of reconstruction, by noting our own experiences.