Mathematical, soulless, insensible to any emotion. So was primal matter of which all on earth are made, rock and water, tree and grass, metal, animal, fish, worm, and men. But somewhere, somehow, something was added to this primal matter, combined with it—used it. It was what we call life. And life is consciousness. And therefore largely emotion. Life establishes its rhythm—and its rhythm being different in rock and crystal, metal, fish, and man—we have these varying things.

“Well, it seems that life has begun to establish its rhythm in the robots. Consciousness has touched them. The proof? They have established the idea of common identity—group consciousness. That in itself involves emotion. But they have gone further. They have attained the instinct of self-preservation. They are afraid mankind will revolt against them. And that, my wise friend, connates fear—fear of extinction. And fear connates anger, hatred, arrogance— and many other things. The robots, in short, have become emotional to a degree. And therefore vulnerable to whatever may amplify and control their emotions. They are no longer mechanisms.

“So, Lao, I have in mind an experiment that will provide me study and amusement through many years. Originally, the robots are the children of mathematics. I ask—to what is mathematics most closely related? I answer—to rhythm—to sound—to sounds which raise to the nth degree the rhythms to which they will respond. Both mathematically and emotionally.”

Lao said: “The sonic sequences?”

Narodny answered: “Exactly. But we must have a few robots with which to experiment. To do that means to dissolve the upper gate. But that is nothing. Tell Maringy and Euphroysne to do it. Net a ship and bring it here. Bring it down gently. You will have to kill the men in it, of course, but do it mercifully. Then let them bring me the robots. Use the green flame on one or two—the rest will follow, I’ll warrant you.” The hill behind where the old house had stood trembled.