the time has passed away when the Spirit of God was comprehensible, and that the divine sense of the world is forever lost? That of old all things were manifestations of the Spirit, but that now we see only lifeless reflections which we do not understand, and live entirely on the fruits of better times? I believe we must humbly confess that the key of this book is not to be found on the common pathways of the human mind. That key is not meant to open earthly doors, and we must deserve it by withdrawing ourselves as far as possible from the earth. One guide, indeed, we may still meet at these lonely cross-roads, who can point out the last way-marks towards these mysterious isles of fire, these Icelands of abstraction and of love. That guide is Plotinus, who attempted to analyse, by means of the human intellect, the divine faculty which here holds sway. He experienced the same ecstasies (as we say in a word which explains nothing) which are in their essence only the beginning of the complete discovery of our being; and in the midst of their trouble and their darkness, he never for one moment closed the questioning eye of the psychologist who seeks to explain to himself the most abnormal phenomena of his soul. He is thus like the last outwork of the pier, from which we may understand something of the waves and the horizon of that dim sea. He tries to extend the paths of the ordinary intellect into the very heart of these desolations, and this is why we must constantly revert to him, for he is the one analytical mystic. For the sake of those who may be tempted to undertake this tremendous journey, I give here one of the pages in which he has attempted to explain the organism of that divine faculty of introspection:--