Thanks for the reference. I couldn't recall exactly how it was explained. Certainly most sci-fi requires you to suspend belief and that is fine. Often there are technologies employed to make a movie interesting. Technologies that are very unlikely to be possible.

In the Matrix, everyone was in a virtual reality and as you quoted, they could have entirely made up physics as we know it. Possibly a perpetual motion machine is viable in the real universe and that is the belief you need to suspend. Which again is fine But it is such a weak minor plot. If that were possible, why use humans? It should be possible with some algae slurry or by mechanical methods or as said, just use animals. Non if them would be a threat. In other words, what makes humans so unique that only they alone can fill this function?

As someone said earlier, the books suggested the computers wanted the processing power of the human brain. That is a fairly easy concept to explain, is an item unique to humans alone and actually in a far future society, might be something that is truely possible. It hardly required you to even suspend belief. Not sure why they didn't go with that.