I find that the policies built on "logic only" tend to break down because they ignore emotion and feelings entirely. People are emotional by nature and our feelings, sense of well-being, sense of justice, sense of oppression, and so on are very real in that they drive how we react and respond to each other. Trying to make a utopia based on people not reacting to their emotions is like trying to make a utopia where people don't need to eat - it might be nice, but it's unrealistic.
Imagine if someone came up and kept stabbing you with a rusty pin every day, and whenever you jump away and say "ow!" they roll their eyes and say "logically, this shouldn't bother you, because it only hurts for a second, you're not bleeding and I know that this pin won't give you tetanus. You're being very irrational right now." Based on their logic, they're right, you won't be measurably hurt, but it still has a real effect on you and you'll want to do everything you can to stop getting randomly stabbed by a rusty pin every day. Your lived experience is real to you.
Seconding this. A doctor showed me one stretch for the backs of my upper legs that got rid of my back pain. Follow the other advice here and see a doctor if it's bad, but leg stretches are free and easy so it's worth a try.
Stand on one leg and put your other leg up straight on a surface like a chair or bed so your legs are pointing at 6 and 3 on a clock. Keep your raised leg straight so your toes are pointing at the ceiling (not bent at the knee or twisted). Lean into it as much as you can while keeping both legs totally straight.
It doesn't seem like much of a stretch, but if it's hard to do, that may be your problem muscle group that's locked up and causing the pain.