"What questions?" Dane laughed again. "Can't you guess? I want to know that man who claimed I was his slave. About the silver needle. The Kalquoi. Who I am; why I can't remember anything; how it is I've no record in your files. Maybe even about you and what you're up to. Things like that, a lot of them."

New lines etched Nelva's lovely face. "Clark, you can't!"

"Can't I?" Dane paced the floor. "Take me there and we'll see whether I can or not!"

"No, no! You don't understand." Nelva's hands moved in a gesture of frustration. "It's just not that easy to use an analytical computer."

Dane stopped his pacing. He frowned. "How's that?"

"For one thing, the machine's self-limiting. It covers only certain areas of information, likely to be needed here on Mars. But your questions aren't localized."

"Give me an example."

"The Kalquoi. They're a menace to all the inner planets, not just Mars. So when you ask about them, the only answer our machine will give you is a referral to the big System Computer on Luna."

"Go on."

"Even setting up a question properly can take weeks. You have to be sure it's framed within the machine's limitations. Take this man you talk about. I wouldn't begin to know how to key a query on him, with nothing to start from but your verbal description of an emotionalized visual image."