"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 re-create 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.