Hey, just curious, why not? Just sick of the forum getting clogged with nutty ideas, I guess? :P
Because this is a science website dedicated to science education and perpetual motion is entirely unscientific and provably impossible.
That's most of it, yes. We used to have a forum called "theory development" and you can only imagine what a cesspool it was! PF is a popular forum, probably the most popular of its type on the internet, and as a result, every crackpot wants in!
Another reason, though, is that such discussions tend not to go anywhere - crackpots are called crackpots for a reason: they aren't interested in learning. So why bother with threads that never go anywhere? This policy does mean we sometimes stifle sincere questions, but I, anyway, tend to PM people who seem sincere with an explanation of the problem with their understanding when I lock such a thread.
....moving to feedback.
Okay, so you're simply tired of dealing with it! XD That makes sense.
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