in finding himself compelled to develop the method of phenomenological reduction, he makes the discovery that in fact no one actually arrives in his ordinary self knowledge at his true and actual self, the being which is his own as ego subject and as the subject of all his world knowledge and mundane accomplishments, that all this shows itself only through the reduction, and that pure psychology is nothing other than the infinitely toilsome way of genuine and pure self knowledge; but the latter also includes knowledge of human beings, as knowledge of their true being and life as egos or as souls; and then it includes also the knowledge of the true being of the world, which in principle no positive science, no matter how successful, can ever attain.