I suppose I stared dumbly. It occurred to me suddenly that the brain of the great van Manderpootz was cracking. "What the — ?" I gasped.

"That," he said blandly, "is but a concept. I have many another use for the toy. I can prove anything with it, anything I wish."

"You can? Then prove something."

"Name your proposition, Dixon."

I hesitated, nonplussed.

"Come!" he said impatiently. "Look here; I will prove that anarchy is the ideal government, or that Heaven and Hell are the same place, or that — "

"Prove that!" I said. "About Heaven and Hell."

"Easily. First we will endow my robot with intelligence. I add a mechanical memory by means of the old Cushman delayed valve; I add a mathematical sense with any of the calculating machines; I give it a voice and a vocabulary with the magnetic-impulse wire phonograph. Now the point I make is this: Granted an intelligent machine, does it not follow that every other machine constructed like it must have the identical qualities? Would not each robot given the same insides have exactly the same character?"

"No!" I snapped. "Human beings can't make two machines exactly alike. There'd be tiny differences; one would react quicker than others, or one would prefer Fox Airsplitters as prey, while another reacted most vigorously to Carnecars. In other words, they'd have — individuality!" I grinned in triumph.

"My point exactly," observed van Manderpootz. "You admit, then, that this individuality is the result of imperfect workmanship. If our means of manufacture were perfect, all robots would be identical, and this individuality would not exist. Is that true?"