## A Proof Against Software Patents

Linked to from a comment on Slashdot, this guy has used computability theory and lambda-calculus to produce a proof that a patent infringement condition exists between any two pieces of software:

http://www.juergen-ernst.de/info_swpat_en.html

Be warned - it's heavy going and English is obviously not his native language. Even if you dont have the stomach to wade through the lambda-calculus proofs, it's interesting to read the summaries to get an idea of just how silly the idea software patents can be. In particular, he shows that some of the fundamental assumptions of the patent system fall apart when dealing with computational algorithms.