The Time Traveller (for so it will be convenient to speak of him) was expounding a reconditematter to us. His pale grey eyes shone and twinkled, and his usually pale face was flushed andanimated. The fire burnt brightly, and the soft radiance of the incandescent lights in the lilies ofsilver caught the bubbles that flashed and passed in our glasses. Our chairs, being his patents, embraced and caressed us rather than submitted to be sat upon, and there was that luxurious afterdinner atmosphere, when thought runs gracefully free of the trammels of precision. And he put it tous in this way-marking the points with a lean forefinger-as we sat and lazily admired hisearnestness over this new paradox (as we thought it) and his fecundity."You must follow me carefully. I shall have to controvert one or two ideas that are almostuniversally accepted. The geometry, for instance, they taught you at school is founded on amisconception.""Is not that rather a large thing to expect us to begin upon?" said Filby, an argumentative personwith red hair."I do not mean to ask you to accept anything without reasonable ground for it. You will soonadmit as much as I need from you. You know of course that a mathematical line, a line of thicknessnil, has no real existence. They taught you that? Neither has a mathematical plane. These things aremere abstractions.""That is all right," said the Psychologist."Nor, having only length, breadth, and thickness, can a cube have a real existence.""There I object," said Filby. "Of course a solid body may exist. All real things-""So most people think. But wait a moment. Can an instantaneous cube exist?""Don't follow you," said Filby