III
“Oh, yes, and Jamieson had a feeble paper on what he called individualization in marine worms. Barr, have you ever thought much about the larger aspects of the problem of individuality?”
Jack jumped slightly. He had let his thoughts wander very far.
“Not especially, sir,” he mumbled.
The house was still. A few minutes after the professor’s arrival, Mrs. Kesserich had gone off with an anxious glance at Jack. He knew why and wished he could reassure her that he would not mention their conversation to the professor.
Kesserich had spent perhaps a half hour briefing him on the more important papers delivered at the conferences. Then, almost as if it were a teacher’s trick to show up a pupil’s inattention, he had suddenly posed this question about individuality.
“You know what I mean, of course,” Kesserich pressed. “The factors that make you you, and me me.”
“Heredity and environment,” Jack parroted like a freshman.
Kesserich nodded. “Suppose—this is just speculation—that we could control heredity and environment. Then we could recreate the same individual at will.”
Jack felt a shiver go through him. “To get exactly the same pattern of hereditary traits. That’d be far beyond us.”
“What about identical twins?” Kesserich pointed out. “And then there’s parthenogenesis to be considered. One might produce a duplicate of the mother without the intervention of the male.” Although his voice had grown more idly speculative, Kesserich seemed to Jack to be smiling secretly. “There are many examples in the lower animal forms, to say nothing of the technique by which Loeb caused a sea urchin to reproduce with no more stimulus than a salt solution.”
Jack felt the hair rising on his neck. “Even then you wouldn’t get exactly the same pattern of hereditary traits.”
“Not if the parent were of very pure stock? Not if there were some special technique for selecting ova that would reproduce all the mother’s traits?”
“But environment would change things,” Jack objected. “The duplicate would be bound to develop differently.”
“Is environment so important? Newman tells about a pair of identical twins separated from birth, unaware of each other’s existence. They met by accident when they were twenty-one. Each was a telephone repairman. Each had a wife the same age. Each had a baby son. And each had a fox terrier called ‘Trixie.’ That’s without trying to make environments similar. But suppose you did try. Suppose you saw to it that each of them had exactly the same experiences at the same times …”
For a moment it seemed to Jack that the room was dimming and wavering, becoming a dark pool in which the only motionless thing was Kesserich’s sphinx-like face.
“Well, we’ve escaped quite far enough from Jamieson’s marine worms,” the biologist said, all brisk again. He said it as if Jack were the one who had led the conversation down wild and unprofitable channels. “Let’s get on to your project. I want to talk it over now, because I won’t have any time for it tomorrow.”
Jack looked at him blankly.
“Tomorrow I must attend to a very important matter,” the biologist explained.