I meant that the cosmic rays eat away at the livable atmosphere and as a byproduct we get a less livable atmosphere. Normally we're protected from any harmful amounts of radiation and the atmosphere can sustain itself (as livable) against what little it gets. The atmosphere leaking into space is a bit far-fetched.
There was a small Wikipedia debate a couple months back. And no, it wasn't me vs. everyone, it was more like 2 vs. 2.
http://www.touchds.com/forums/lounge/4829-research.html