By letting inventors use their inventions without trolls getting in the way. The patent system doesn't recognize independent invention though reality does.

Imagine having your valuable R&D rendered worthless by an injunction prohibiting you from distributing your product, that's what patents do.

Very little of what patents describe could be called original and they aren't described in a way to help people learn. While congress may have enacted them thinking they'd spur invention it's pretty obvious to developers operating in a patent-laden world that they do nothing of the sort. We aren't allowed to look at patents and when we do they aren't written to educate but to obfuscate. When our companies milk us for ideas they aren't interested in our ground-breaking earth-changing ideas, but simple (easily infringed) ways to do [common thing] [in a slightly new medium].