Moonwind's primary theme is the gap between aspirations and reality. Both of the main characters are haunted by this gap. Gareth, a Welsh boy who wins a contest to visit the moonbase, was only dimly aware of his dissatisfaction before. Nevertheless this awareness resulted in his winning essay on the Lunacy Syndrome, which looks at "space sickness" as the darker side of the religious conversion which occurs to many visitors. When Gareth himself arrives on the moon, he begins to hate the prospect of returning to Earth. At the same time he has episodes of disorientation and perceptual blurring, which only strengthen his belief that he is destined for another life entirely.

Bethkahn, a young woman of an advanced species who live without bodies, has seen her aspirations cruelly cut off. On her first voyage as a new member of a spaceship's crew, the...