Something in the ring of his voice, in the determined set of his lower face, told her he was speaking the truth. She said, "All right, what purpose gives you the right to come to Earth, to violate everything I cherish, to make me a voluntary kidnapee, to wreck my life and drag me off to a planet I haven't even been trained for? What's to prevent me from reporting it and having you arrested?" "Nothing," he replied, "except that I'd probably be released as soon as we reached Mars. If you still feel like this when we get there tomorrow I shan't stand in the way of your returning." There was a new sag in his shoulders, a weariness to the lines about his mouth. "Oh, great!" she retorted. "Smash my job, my personal life, then say you won't try to stop me from going back to it. How _can_ you go around with so few ethics? What sort of person are you anyway?" "A very serious one--a very worried one," he told her quietly and her quick probe of his thoughts revealed him again to be speaking the truth. He captured both her arms again, held her gently against the wall, and so great was the hypnotic force of his personality that despite her anger toward him she made no move to break away. "You have a right to know--_now_," he told her. "I'm a Martian, a third generation one, even though I was born and trained on Earth. Conditions out there are only just beginning to be fit for human infants. We're building the biggest thing Man has ever accomplished on Mars--making a barren ruined planet live again, making it fit for men and women and babies to inhabit. "Right now we're up against the greatest danger we've faced since the first few desperate years--maybe an even greater threat. We can't see it, we don't even know what it is. But men and women on Mars are going mad. Only a few of us can reach them--and thanks to a condition of the planet we're all too overloaded to do the psychiatric work we should do. We need telepaths." A flash of something she had heard or read somewhere about the red planet occurred to her. She said, "But doesn't the atmosphere or something of Mars encourage telepaths? _You're_ one. Why come to Earth for them? Why pick on me?" "Because," he told her with the patience of exasperation, "we need at least to maintain those telepaths we have--which aren't nearly enough. You don't seem to realise that a genuine two-way telepath, even among fourth generation Martians, occurs only about once in eleven thousand six hundred births. And we need more than the few we have for communications alone." "Communications!" Lynne was honestly shocked. "Do you mean to tell me that Mars has no--"