Soft Science Fiction: 15 Classic and Contemporary Must Read Books

"Sci-fi writers take current scientific knowledge and extrapolate forward, imagining what the future or an alternate world will look like. In general, hard sci-fi is closer to current science, whereas science fiction that gets further away from what is presently known is considered soft. Consequently, hard science fiction is rooted in the physical and natural sciences, and considered to be more realistic.
In contrast, soft science fiction tends to focus more on the social sciences and be more outwardly philosophical in approach. The Star Trek franchise is a good example of soft sci-fi. The series is well-known for exploring social and political issues within a futuristic, space-opera setting. However, less explored is the science behind how most of the alien races on Star Trek are humanoid in appearance, which would be hard sci-fi territory."