Task of Tau

Tau was metal. Tau was chemical. Tau was electrical. Yet Tau could face death like a man.
A gleaming binary swung in the blue sky, sending a moist warmth across the swaying fern-growths of the Fourteenth Planet . Feathered creatures of bright colors flashed through the underbrush and made noises there. A figure came stalking down through the shaded clearings, and small scaly bodies scurried out of sight, leaving ungainly tracks scrawled in the swamp mud.
Tau, the metal man, a mechanical half-sentient messenger from the far distant past, strode impassively along, not heeding the smaller creatures of the jungle. He had sighted the tiny habitable world from the distant depths of an outer galaxy, and had moored his space-ship in a clearing that was not distant.
He halted his berylite six-foot body in a leafy glade and let the wind play about his cold outer surface. The lens-cased inscrutable orbs in his head peered about, taking in the scene with photographic detail.
Life! This is life! he thought to himself. This is the life the Master said I would find some day.
Though his memories were of a distant past, of a remote planet, and of the Master whose atoms might lie even now in the etheric dust, Tau remembered with perfect clarity. He could recall the aged countenance of the Master, the broad forehead, the jutting chin, and the determined undertone of his deep voice.
Men may die, the Master had said, but their deeds live after them. And Kendall Smith's face had lighted inwardly as though from some deep inspiration. Tau had said nothing in reply, but in the neurochemical mechanisms of his brain the words had been imprinted forever.
You're just a robot, the master had said, with responses and reactions that are the involuntary activations of metal and chemical-change impulse, yet I believe that some day in the aeons which will pass, you will learn to reason for yourself to some extent, and perhaps understand your mission. But you will never live, even though you may carry the germs of life into the far distant future.