True and there is plenty of evidence he lifted it from the works of other writers.
From A.E. Van Vogt's 1948 The Players of Null-A
From his height of greater understanding he assured the younger individual that the affective incident must be looked at from a different angle than that of a frightened youth. Assured him that fear of pain and fear of death were emotions that could be overcome, and that in short the shock incident which had once affected him so profoundly no longer had any meaning for him. More than that, in future he would have better understanding of such moments, and he would never again be affected in an adverse fashion.
It was one more Null-A training make-shift, as had been all the others. But is was a system of self-therapy that was scientifically sound, and which would bring definite benefits.
"Relax," the voice soothed on. And because of what he was doing, every word meant, "Relax the tensions of a life time. Let all those past fears and doubts and uncertainties be discharged from the nervous system."
The effect did not depend on any belief that something would happen, though conviction made it more powerful. But it would take time. There were many suppressed memories that would have to be skilfully brought out in the open, before the therapy could be used on them.
...
