I can only guess that it made the world he went back to. . . strangely without meaning. Though he lived in it, though he even enjoyed it, it remained utterly remote. I think it had lost sense for him. In his heart was the reflection of a lovely dream that he could never quite recall.
Although it is uncertain, it is necessary to make science useful. Science is only useful if it tells you about some experiment that has not been done; it is not good if it only tells you what just went on.