That’s what it was like in the past, for example when Queen Mary reigned (Henry VIII’s daughter) and you could be burned at the stake for studying science. I would be gutted, I can’t ever imagine life like that without freedom to think/study and say what you believe in.
If it was just me that was affected, I think I could just about live with it (although I might cheat on the thinking part if no one could check). Freedom of thought is a very important human right. If this kind of rule affected the whole society and was imposed on me by a government, I would think this was really unacceptable, and I hope I would be brave enough to rebel against the state I was living in. Unfortunately, this does happen from time to time in human history, and people have to be very brave and stand up against it. You can bet that any government that doesn’t allow people to think for themselves and look at the evidence (which is really the essence of science) does not have their best interests at heart.