In so many of these controversies, these arguments, the basic parameters for the argument are never clearly stated.
For example, a politician was talking on the radio recently about the tax cuts of 1981 and 1986, and he was saying that it was their position at the time that it would increase the deficit, and in their opinion they were right - and he should have stopped right there, because that's not an established fact, we might want to start by trying to understand whether it did increase the deficit. Let's think about whether we really have any idea whether or not it increased the deficit. If we do have some understanding, we can move forward from that point, and if we don't, the let's acknowledge that, and let's argue on the basis of things we do understand.
And this guy later was making some point about a specific thing, it was about charities, trying to make the point that the tax break is not the only reason people give to charities, because his tax plan would eliminate that tax break, and he said, let's try to understand charities, alright, people give to charities whether or not there is a tax break - and here, even though the politician was explicitly saying, let's slow down and think logically about things, he wasn't giving any evidence, he really wasn't thinking logically about it.