Wired’s Matt Blum asks [geeky questions](http://www.wired.com/geekdad/2009/10/top-10-unanswered-questions-in-geeky-movies-ii-the-sequel/) about popular sci-fi movies, including one that’s [always bugged me](http://johnaugust.com/archives/2006/why-the-matrix-trilogy-ultimately-blows):
> 8. The Matrix: Why do the machines need humans?
> The intelligent machines have all humans hooked up to elaborate devices to harvest their body heat and chemicals, right? But they also have sophisticated fusion reactors. The energy production of fusion reactors compared to that of humans (with all the maintenance required, including The Matrix itself) is so much more efficient it’s just ridiculous -— and we’re supposed to believe that intelligent machines, which would presumably operate logically, would keep the humans around anyway? It’s obviously necessary for the plot, but it just makes no sense.
But what would make sense is if humans were used not as batteries, but rather as organic CPUs.
For all its processing power, perhaps the Matrix can’t do something that human brains can. So they use the connected humans as a fleshy cloud computer to keep the Matrix running.
As a viewer, I’d be willing to accept an incredibly simple answer here. On page 50, instead of…
MORPHEUS
The human body generates more bio-electricity than a 120-volt battery and over 25,00 B.T.U.’s of body heat.
…how about…
MORPHEUS
The human brain is slow and imperfect, but it can do things silicon can’t. It can imagine, create. It can stitch together ideas to form something new. That’s why they need us -- so they can evolve.