I searched the internet for the right definition of what Science Fiction is; but, there were very few choices to pull from. Here is one I liked:
“Science fiction allows us to understand and experience our past, present, and future in terms of an imagined future.” —Kathryn Cramer, The Ascent of Wonder (1994)
Let’s turn to Wikipedia to look more closely to what “science” entails:
” ‘Science’ refers to the body of reliable knowledge itself, of the type that can be logically and rationally explained.”
In order words, you need to have physical evidence to support that this particular hypothesis is true, and not junk science; however, not everything can be physically proven. In the past (not so much now), this was where philosophy came in; hence, could this hypothesis be “logically and rationally explained” by using observations and assumptions that could be supported through experimentation?
Science fiction is different from Fantasy in that it is based on possibilities, whereas Fantasy is well, not (entirely) possible.
For those who grew up during the 1950s and 1960s, how many Science Fiction stories have you watched (Star Trek anyone?) or read where certain technology has been taken and made into reality today? Does any specific gadgets come to mind?
Those who write Science Fiction are fascinated with the seemingly unlimited possibilities, with what mankind can accomplish when using various forms/areas of science whether it be for good or for evil. There are those who write to explore the many possible outcomes through alternate worlds or timelines (what would our world be like if Germany had won World War II?), or explore the consequences of various types of technology (what would our world be like if computers took over, and mankind became either slaves or extinct?).
Science is a very broad field which provides writers with almost endless choices for story ideas when writing fiction.