What is the difference in emphasis between the terms science fiction and speculative fiction? Which is The Man in the high Castle?

Suvin describes science fiction as a literary genre that necessary and sufficient conditions are the presence and interaction of the different, imaginative and cognitive where the tool is a creative alternative environment different to the authors own. "By imagining strange worlds we come to see our own conditions of life in a new and potentially revolutionary perspective" (Roberts, 2006.). Science Fiction uses imagery or less plausible ideas / content in the novels. Often they are based in futuristic settings like future science, technology, universes and aliens. It gives its audience a different world that is comparative to us and that we should see our differences and attempt to bring change in society. 

However speculative fiction is based on an alternate form of history, supernatural fiction, and weird fiction and so on and it is mostly considered as a different kind of science fiction that has more philosophical lines and difficult themes in the setting of its world.  

Simply, Speculative fiction would be a subset of the more 'umbrella' term Science Fiction. In Speculative fiction you have to think about a "What if" condition. This condition can be realistic or not and the rest of the story has to revolve about it in more strict scientific rigor.

For example "What if you had a machine capable of transporting you through time?" In H. G. Wells story 'The Time Machine' this is the only fantastic element. The entire rest of the story adheres to strict reality. As most science fiction can be interpreted as speculative fiction the two terms are often mistaken as being the same thing.

Brown, E (2001) explains that the mental cognition of the characters in the novel in close relationships cannot expect the fate of future without their understanding of each individual character. Also, Brown mentions that “Dick suggests that the world presented in “The Man in the High Castle' is but an illusion, that other, better worlds might exist”

In conclusion Speculative Fiction is more related with Philosophy and some histories. Also ’The Man in the High Castle’ has many themes like totalitarianism and Eastern philosophy. Therefore “The Man in The High Castle” is a speculative novel because of its psychological depth and sophistication.

Reference

Brown, E. (2001). Introduction. In Dick, P.K.,The Man in the High Castle (p.v-xii). London: Penguin.

The Man in the high Castle (2014).Wikipedia. Retrieved from http://en.wikipedia.org/wiki/The_Man_in_the_High_Castle

Roberts, A. (2006). The history of science fiction. Hapmshire: Palgrave Macmillan.