alt Hacker News> If changing the laws of the universe is fine, then nothing gets excluded even Harry Potter
the laws of the universe in Harry Potter are so fickle and ever changing with the plot line that to me, it can only be considered soft. compare with Egan who takes a given cosmology and then works 100% within that world. that's hard.
That’s not a question about the underlying rules of a fictional work but your perception of how they are created. It’s possible to have a completely well defined fantasy setting with exact rules without the reader being aware of what those rules are or even knowing it’s using well defined rules.
Consider The Martian, early versions where posted online and the author changed what resources the character had to work with at the beginning. So what feels like a creative solution to limited resources was really giving the character exactly what they needed after a solution was found. Only examining a work we can’t distinguish ‘soft’ physics updated as the plot demands from a story based around fixed rules.