I watched one of the Foundation trailers the other day, and suddenly realized something that I feel isn't quite right.
- You're familiar with my work, psychohistory? - Every mathematician has read your theory... - It's not a theory. It's the future of mankind, expressed in numbers.
This is just annoying. I suspect Asimov, being a man respectful of science, might have wrinkled his nose, had he learned of this dialog between Seldon and Dornick. It is not borrowed from the book as far as I can recall.
Psychohistory obviously qualifies as a scientific theory. That last sentence just underpin that it is indeed a scientific theory he's speaking about.
In everyday speech people will use the word "theory" to mean something different than what it means when used as part of the term "scientific theory". Einstein's theories on relativity are scientific theories. Newtons theories, on so much, are scientific theories. Saying "it's not a theory" reflects the common citizens understanding of the word "theory", and not the almost totally opposite meaning it has when speaking of science.
Well, it's not a big deal. It's just that I like the science in sci-fi to be correct in every detail, except for the parts that obviously are fiction.
So this Doctor Who takes Rose "one hundred years forward in time, to the 21st century". Only trouble is ... Rose and all of us are already in the 21st century. Go one hundred years forward, and you're somewhen in the 22nd century. Would have thought the time traveling Doctor knew this.