The doctor looked perplexed. "But this illness still surprises me," he said. "I've examined him almost monthly for the past year, and frankly, I would have bet on his survival. He began to improve rapidly—physically, anyway. It might have been the lesser gravity, or the healthier life." He looked at the captain curiously. "Yet he wasn't assigned to any over-strenuous duties?"
"You know he wasn't," said the captain. "We don't want anybody to undertake work they can't handle. His labor was hardly physical. He worked in the geological and botanical groups, but not in the field. He did classifying and clerical work."
"Then that wouldn't account for the trouble—"
"Perhaps it does, in a way," The captain bent over the puffy, chalk-white face of the industrialist, listening to his shallow breathing. "He was never happy doing it. He had different ideas about himself than we did. He never understood what we were doing or why."
"It's the greatest mystery of them all," said the physician, shaking his head.
"What is?"
"The human body. It's incredible how much we've learned about the physical world, and even the physical features of our own construction. But there's still a mystery we haven't penetrated—"
The captain smiled. "That doesn't sound like you."
"I know," the young physician answered. "But when I see a case like this—a man breathing his life away for a reason I really can't understand—" The doctor rubbed the back of his head. "I know it's crazy, and old-fashioned, and doesn't make the least bit of sense in these scientific times, Captain. But if anyone were to ask me—off the record, and completely unofficially—I could only give them one honest diagnosis of this case. I think this man is dying of a broken heart."