“I know what that means when a mathematician says it. How near the end are you?”

“It all depends.”

“On what?” Ashe dropped into a chair and stretched his long legs out before him.

“On Lanning. The old fellow disagrees with me.” He sighed, “A bit behind the times, that’s the trouble with him. He clings to matrix mechanics as the all in all, and this problem calls for more powerful mathematical tools. He’s so stubborn.”

Ashe muttered sleepily, “Why not ask Herbie and settle the whole affair?”

“Ask the robot?” Bogert’s eyebrows climbed.

“Why not? Didn’t the old girl tell you?”

“You mean Calvin?”

“Yeah! Susie herself. That robot’s a mathematical wiz. He knows all about everything plus a bit on the side. He does triple integrals in his head and eats up tensor analysis for dessert.”

The mathematician stared skeptically, “Are you serious?”

“So help me! The catch is that the dope doesn’t like math. He would rather read slushy novels. Honest! You should see the tripe Susie keeps feeding him: ‘Purple Passion’ and ‘Love in Space.’”

“Dr. Calvin hasn’t said a word of this to us.”

“Well, she hasn’t finished studying him. You know how she is. She likes to have everything just so before letting out the big secret.”

“She’s told you.”

“We sort of got to talking. I have been seeing a lot of her lately.” He opened his eyes wide and frowned, “Say, Bogie, have you been noticing anything queer about the lady lately?”

Bogert relaxed into an undignified grin, “She’s using lipstick, if that’s what you mean.”

“Hell, I know that. Rouge, powder and eye shadow, too. She’s a sight. But it’s not that. I can’t put my finger on it. It’s the way she talks—as if she were happy about something.” He thought a little, and then shrugged.

The other allowed himself a leer, which, for a scientist past fifty, was not a bad job, “Maybe she’s in love.”

Ashe allowed his eyes to close again, “You’re nuts, Bogie. You go speak to Herbie; I want to stay here and go to sleep.”

“Right! Not that I particularly like having a robot tell me my job, nor that I think he can do it!”

A soft snore was his only answer.

Herbie listened carefully as Peter Bogert, hands in pockets, spoke with elaborate indifference.

“So there you are. I’ve been told you understand these things, and I am asking you more in curiosity than anything else. My line of reasoning, as I have outlined it, involves a few doubtful steps, I admit, which Dr. Lanning refuses to accept, and the picture is still rather incomplete.”

The robot didn’t answer, and Bogert said, “Well?”

“I see no mistake,” Herbie studied the scribbled figures.

“I don’t suppose you can go any further than that?”

“I daren’t try. You are a better mathematician than I, and—well, I’d hate to commit myself.”

There was a shade of complacency in Bogert’s smile, “I rather thought that would be the case. It is deep. We’ll forget it.” He crumpled the sheets, tossed them down the waste shaft, turned to leave, and then thought better of it.