"But the link between you and your brother was not broken. Instead, it became a one-way channel.
"What happens in such a case? The damaged brother, in order to escape the intolerable prison of his own body, becomes a receptor for the stronger brother's thoughts. The weaker feels as the stronger feels. The experience of the one becomes the experience of the other—the thrill of running after a baseball, the pride of doing something clever with the hands, the touch of a girl's kiss upon the lips—all these become the property of the weaker, since he is receiving the thoughts of the stronger. There is, of course, no flow in the other direction. The stronger brother has no way of knowing that his every thought is being duplicated in his brother's mind.
"In effect, the damaged brother ceases to think. The thoughts in his mind are those of the healthy brother. The feeling of identity becomes almost complete.
"To the outside observer, the damaged brother appears to be a cataleptic schizophrenic, completely cut off from reality. And, in a sense, he is."
Stanton walked over to the nightstand by the bed, took another cigarette from the pack, lit it, and looked at the smoke curling up from the tip.
So Martin became a cataleptic schizophrenic, he thought.
The mind of Martin had ceased to think at all. The "Bart" part of him had not wanted to be disturbed by the garbled, feeble sensory impressions that "Mart's" body provided. Like many another schizophrenic, Martin had been living in a little world cut off from the actual physical world around his body.
The difference between Martin's condition and that of the ordinary schizophrenic had been that Martin's little dream world had actually existed. It had been an almost exact counterpart of the world that had existed in the perfectly sane, rational mind of his brother, Bart. It had grown and developed as Bart had, fed by the one-way telepathic flow from the stronger mind to the weaker.
There had been two Barts—and no Mart at all.
But there had been only one human being between them. Bart Stanton had been a strong, capable, intelligent, active human being. The duplicate of his mind was just a recording in the mind of a useless, radiation-blasted hulk.