It could never have been done without hypnosis. Within broad limits, the human body is capable of doing just exactly whatever it _thinks_ it is capable of. But the human body could hardly be blamed if convention had long since decided that exertion was bad, that straining to the limit of endurance was unhealthy, that approaching--even obliquely--the margin of safety of human resiliency was equivalent to approaching death with arms extended. That convention had so declared was well known to the researchers at the Hoffman Center. But it was also known that the human body under the soothing suggestion of hypnosis could be carried up to that margin of safety and beyond. Indeed, it could be carried almost to the actual breaking point without stir, without a flicker of protest, without a sign of fear. And these were the conditions that were critically needed in testing for the Mercy Men. Yet, though hypnosis was necessary, the men who came to the Mercy Men without fail rejected hypnosis. Always they held the fear of divulging some secret of their past. Whether because of distrust of the doctors and the testing in the Center, or plain, ordinary malignance of character--no one knew all the motives. But those who needed hypnosis the most rejected it the most vehemently. This forced the development of techniques of hypnosis-by-force. It would have annoyed Jeff, if he had known. Indeed, it would have driven him to the heights of anger, for Jeff, among other things, was afraid. But he need not have been, and it made little difference that he was. Now Jeff was not suffering from his fear. His mind was in a quiet, happy haze, and he felt his body half-lifted, half-led across the room to the first section of the testing room. Even now there was a tiny, sharp-voiced sentinel hiding away in a corner of his mind, screaming out its message of alertness and fear to Jeff. But he laughed to himself, sinking deeper into the peacefulness of his walking slumber. Dr. Gabriel's voice was in his ear, his voice smooth and soothing, talking to him quietly, giving simple instructions. Quickly, he took him through the paces of a testing series that would have taken long, hard days to complete. It would have left him in psychotic break at the end, if he had not had the recuperative buffer of hypnosis to help him. First, he was dressed in soft flannel clothing and moved into the gymnasium. Recorders were attached to his legs and arms and throat. Then he was formally introduced to the treadmill and quietly asked to run it until he collapsed. He smiled and obliged, running as though the furies were at his heels. He ran until his face went purple and his muscles knotted. At last he fell down, unable to continue.