Prof. Lessig, writing about the current fight against software patents in Europe, reminds us of a bit of wisdom coming from nobody else than Bill Gates:

So here’s perhaps the most concise and compelling account of just why software patents will harm new innovators (that’s you Europe) and benefit old innovators (that’s America), written in 1991 by Mr. Gates:
“If people had understood how patents would be granted when most of today’s ideas were invented and had taken out patents, the industry would be at a complete stand-still today. The solution . . . is patent exchanges . . . and patenting as much as we can. . . . A future start-up with no patents of its own will be forced to pay whatever price the giants choose to impose. That price might be high: Established companies have an interest in excluding future competitors.” Fred Warshofsky, The Patent Wars 170-71 (NY: Wiley 1994).