They experimented with all sorts of rules in the past. The rules that survived are the ones that made the game the most interesting... that's the only real answer for any rule.
Why can't we castle out of check?

Seriously? Why can't we castle out of check. It would make things so much easier.
eh just deal with the rules

They experimented with all sorts of rules in the past. The rules that survived are the ones that made the game the most interesting... that's the only real answer for any rule.
Agreed. What we see today is the current evolution of Chess. It could and probably will change again.
Didn't peg you as a guy who'd use the "e" word, but yeah, I agree.
Think of chess as simulated war. If your king is under immediate threat in the real world it is impossible to wizard/magic him from his exposed location to suddenly appearing safe in his castle.
Castling takes time, time your king does not have when exposed.

Think of chess as simulated war. If your king is under immediate threat in the real world it is impossible to wizard/magic him from his exposed location to suddenly appearing safe in his castle.
Castling takes time, time your king does not have when exposed.
Yes, I think that's it.
If you could castle out of check, that would make the castling move too powerful. Your opponent could create a strong attack on your uncastled king only for you to whisk your king to safety in one move. It would make it too easy to sidestep attacks on your uncastled king.
It's like when Lucy pulls the football away at the last second when Charlie Brown is ready to kick the ball.

I've heard it's because castling was originally done in two consecutive moves, first the rook move and then the king move. When the two moves were combined to speed up the game, people still had the idea that the initial rook move would be illegal if the king was in check. I'm not a chess historian, so I don't know for sure, but that's the explanation I've heard.
Castling was brought in later and so the logic was not to cause too many changes to the game.
Gotcha, I can see why they wouldn't want to change it a lot.