Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world.
The future depicted in a good SF story ought to be in fact possible, or at least plausible. That means that the writer should be able to convince the reader (and himself) that the wonders he is describing really can come true... and that gets tricky when you take a good, hard look at the world around you.
Interpretation
What this quote means
The quote emphasizes the importance of plausibility in science fiction writing, where the future portrayed should be believable.
Frederik Pohl's quote highlights the essential quality of science fiction: that it needs to present a future that is not only imaginative but also possible or plausible. The writer's task is to engage the reader's belief in the potential reality of the depicted wonders, which becomes a complex challenge when one reflects critically on the current state of the world. This invites both the writer and the reader to consider the boundaries between imagination and reality.
Themes
In practice
Example use cases
In a panel discussion about literature, I might quote this to highlight the responsibilities of science fiction authors.
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