Interestingly, it his Siddhartha's desire to leave the Brahmin world that starts his quest, and a Brahmin word that starts him on the path to completion. Siddhartha has come full circle to find his path to enlightenment. This moment of revelation is followed by one of horror brought on by total and complete self-awareness, and the Siddhartha passes out. He awakes from a deep sleep, "and it seemed to him as if his entire long sleep had been nothing but a long meditative recitation of Om," and he is renewed with the simple and profound joy of life and love for all things living (Hesse, Chapter 8). Siddhartha realizes that this was his "sickness;" he had simply been unable to love anything for some time, but after his moment of wretchedness this love comes flooding back to him. The changes he makes at this point are completely internal. Though he has spent the entire novel striving for internal change, he has sought its arrival in almost purely external means -- the complete renunciation of material...

Now, rather than feeding those externalities into himself to see what changes they inspire, he is reflecting his inner joy out at the universe, and passively receiving the joy reflected back at him by the living world. In effect (though it is perhaps trite to say), he is the change that he has so long been seeking; his love is enlightenment.
Siddhartha's journey is not done at this point; he continues to live for many years with the ferryman, and then as the ferryman, before he attains full enlightenment. But this is the ture starting point of his journey to that goal. Though the other attempts he makes in the novel are arguable necessary for his arrival at this point, it is in his moment of abandon by the river that Siddhartha is finally able to accept the world and himself merely for what they are -- representations of a living love that is united and ultimately…