'd think it would be
fairly easy to spot a robotic or a semirobotic brain capable of
controlling a car."

"It might have been, once." Leibowitz said. "But these days the problems
are rather special. Oh, I don't mean we can't do it--we can and we will.
But with subminiaturization, Mr. Malone, and semipsionic circuits, a
pretty good brain can be hidden beneath a coat of paint."

For no reason at all, Malone suddenly thought of Dorothy again. "A coat
of paint?" he said in a disturbed tone.

"Certainly," Leibowitz said, and smiled at him. It was a warm smile that
had little or nothing to do with the problem they were talking about.
But Malone liked it. It made him feel as if Leibowitz liked him, and
approved of him. He grinned back.

"But a coat of paint isn't very much," Malone said.

"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 conc