"It doesn't have to be very much," Leibowitz said. "Not these days. I've often told Emily--that's my wife, Mr. Malone--that I could hide a TV circuit under her lipstick. Not that there would be any use in it--but the techniques are there, Mr. Malone. And if your conjecture is correct, someone is using them." "Oh," Malone said. "Sure. But you _can_ find the circuits, if they're there?" Leibowitz nodded slowly. "We can, Mr. Malone," he said. "They betray themselves. A microcircuit need not be more than a few microns thick, you see--as far as the conductors and insulators are concerned, at any rate. But the regulators--transistors and such--have to be as big as a pinhead." "Enormous, huh?" Malone said. "Well," Leibowitz said, and chuckled, "quite large enough to locate without trouble, at any rate. They're very hard to conceal. And the leads from the brain to the power controls are even easier to find--comparatively speaking, of course." "Of course," Malone said. "All the brain does, you see," Leibowitz said, "is control the mechanism that steers the car. But it takes real power to steer--a great deal more than it does to compute the steering." "I see," Malone, who didn't, said desperately. "In other words, unless something radically new has been developed, you can find the circuits." "Right," Leibowitz said, grinning. "It would have to be something very new indeed, Mr. Malone. We're up on most of the latest developments here; we've got to be. But I don't want the credit for this." "No?" Malone said. "Oh, no," Leibowitz said. "All I do is work out the general application to theory, as far as actual detection is concerned. It's my partner, Mr. Hardin, who takes care of all the engineering details." Malone said: "Well, so long as one of you--" "Sal's a real crackerjack," Leibowitz said enthusiastically. "He has an intuitive feel about these things. It's really amazing to watch him go to work." "It must be," Malone said politely. "Oh, it really is," Leibowitz said. "And it's because of Sal that I can make the guarantee I do make: that if there are any unusual circuits in those cars, we can find them." "Thanks," Malone said. "I'm sure you'll do the job. And we need that information. Don't bother to send along a detailed report, though, unless you find something out of the ordinary." "Of course, Mr. Malone," Leibowitz said. "I wouldn't have bothered you except for the production speed-up here." "I understand," Malone said. "It's perfectly all right. I'll be hearing from you, then?" "Certainly, Mr. Malone," Leibowitz said. * * * * * Malone cut the circuit at once and started to turn away, but he never got the chance. It started to chime again at once. "Federal Bureau of Investigation," Malone said as he flipped up the receiver. He wanted badly to copy Boyd's salutation, but he found that he just didn't have the gall to do it, and said sadly instead: "Malone speaking."