Complementarity cuts both ways I was reading through Murphy's testimony and came across this gem:

In economics, complementarity always runs in both directions. Lower price for gas, more demand for cars. More cars, more demand for gas. It goes bothways.

This is just the flip side of the argument made by the court that the emergence of middleware generates demand for more operating systems. You can't have one without the other. The two reflect the same underlying economic principles. But people don't always realize this one even though they realize the first one.

I thought there had been a sudden explosion in operating systems recently, and now I know why--the growth of middleware creates demand for specialized operating systems, so they appear. I'm betting that this is what Tim O'Reilly's emergent Internet operating system will look like, an archipeligo of middleware linked by many languages and protocols. Nice.