premise: I think it's an issue that we need to take very seriously. But I don't think we know the solution to global warming yet. And I don't think we've got all the facts before we make decisions. I tell you one thing I'm not going to do is I'm not going to let the United States carry the burden for cleaning up the world's air. Like Kyoto Treaty would have done. China and India were exempted from that treaty. I think we need to be more even-handed, as evidently 99 senators -- I think it was 99 senators supported that position.
hypothesis: There is no definitive solution to global warming. 
reason: It says that the solution is not yet known, so the statement that there is no definitive solution to global warming is correct.