 What is the unspoken warning of the psychologist?
Flight Officer Robert Craig surrendered the tube containing his service record tapes and stood waiting while the bored process clerk examined the seal. It helps suppress certain physiological reactions to an entirely new set of conditions. During the days that followed, the psychologist seemed to Craig to become progressively more didactic. But even if he could accept the psychologist's authority for the cumulative effect of a gravity system, he could not understand the unspoken warning he felt underlying all that the man said. On the eighth day, two attendants, who showed the effects of massive doses of PON to protect themselves from the centrifugal force, had to carry a man out of the tank. "Not to Chociante, if that's what you mean.
 The culture on Terra is radically different from the culture in space.
 Even good jobs get boring on Terra.  Private citizens do not enjoy the same rights as spacemen.  The culture on Terra is radically different from the culture in space.  The gravity on Terra could make a spaceman feel sick all the time.