Groklaw, "An Explanation of Computation Theory for Lawyers," from back in late 2009:
Consider the following list of statements.
* All software is data.
* All software is discovered and not invented.
* All software is abstract.
* All software is mathematics.
If my understanding of the US patent law is correct, whether or not any of these statements is true could determine whether or not software is patentable subject matter. The resolution of this issue has serious consequences to the computer electronics and software industries.
When you know computation theory, you know without a shred of a doubt that each of these statements states a fact that is grounded in well-established mathematics. If you don't know computation theory, these statements will probably look to you like debatable issues.