I think he refers to people as liars when they know that what they are saying is false.
Right, but there are two problems with that:
First, he refers to them as liars when he
thinks what they are saying is false.
Second, he makes no distinction as to whether or not there was malicious intent. For example, if a friend of mine tells me, "wow, I haven't seen you in at least two years", he's not "lying" if we saw each other 23 months ago - he was rounding up, made a mistake, etc.
Gravy assumes (in almost every situation I've witnessed) that a person who ultimately disagrees with him about 9/11 is maliciously lying about any point of contention.
The example that sticks out most in my mind is Scott Forbes - instead of acknowledging that Scott could have been (and almost certainly was) recalling his
perception of the partial WTC power down, Gravy concluded that Scott was maliciously lying for the sole purpose of gaining attention.
Of course, there's absolutely no evidence to suggest anything of the sort, as Scott gained no positive attention before he stopped commenting on the matter publicly due to threats against him, and possibly his family and/or coworkers (or something of the sort).