Here, too, the expression is still helpless, but though the flesh is weak, the spirit is very willing. The expression, "He who has bones" is meant for that which has assumed consistency and form, the Visible, as opposed to that which has no bones, no body, no form, the Invisible, while "breath, blood, and self of the world" are but so many attempts at finding names and concepts for what is by necessity inconceivable, and therefore unnamable.
In the second period of Vedic literature, in the so-called Brâhma_n_as, and more particularly in what is called the Upanishads, or the Vedânta portion, these thoughts advance to perfect clearness and definiteness. Here the development of religious thought, which took its beginning in the hymns, attains to its fulfilment. The circle becomes complete. Instead of comprehending the One by many names, the many names are now comprehended to be the One. The old names are openly discarded; even such titles as Pra_g_âpati, lord of creatures, Vi_s_vakarman, maker of all things, Dhât_ri_, creator, are put aside as inadequate. The name now used is an expression of nothing but the purest and highest subjectiveness--it is  t m a n, the Self, far more abstract than our E g o--the Self of all things, the Self of all the old mythological gods--for they were not _mere_ names, but names intended for something--lastly, the Self in which each individual self must find rest, must come to himself, must find his own true Self.
You may remember that I spoke to you in my first lecture of a boy who insisted on being sacrificed by his father, and who, when he came to Yama, the ruler of the departed, was granted three boons, and who then requested, as his third boon, that Yama should tell him what became of man after death. That dialogue forms part of one of the Upanishads, it belongs to the Vedânta, the end of the Veda, the highest aim of the Veda. I shall read you a few extracts from it.
"Men who are fools, dwelling in ignorance, though wise in their own sight, and puffed up with vain knowledge, go round and round, staggering to and fro, like blind led by the blind.
"The future never rises before the eyes of the careless child, deluded by the delusions of wealth. _This_ is the world, he thinks; there is no other; thus he falls again and again under my sway (the sway of death).