I'm not a very pleasant person.
Yes, I know - what a shock, right?
It's as true as it is obvious, and I'm as aware of it as anyone else. I have a pretty short temper for what I consider bullshit, and my definition of 'bullshit' overlaps with what many other people call 'politeness'.
Beyond that, I handle bullshit in fairly direct ways - if I suspect someone is full of shit, I generally only spend so much time trying to carefully, masterfully tease them out of their labyrinthine network of claims and contradictions in the hope of forcing them to admit that they are, in fact, inconsistent. I'm more likely to walk, tell them to piss off, or some combination thereof. I do this a lot quicker than most people, and to be perfectly frank, I even sometimes do it when I shouldn't. I do make mistakes. Unfortunately, those mistakes are mixed in with the prudent judgment calls, and they aren't always the easiest to sort out. If you ask me, my batting average is pretty damn good on this front.
I make no apologies for any of this. In fact, the point of this post is not to explain myself, or even defend what I do, but to go further and suggest that you, too, may well benefit from sometimes telling people 'I think you're full of shit, and I'd rather not deal with you anymore.'
I especially advise this of people conscious of the culture war. If you believe that's a war worth fighting, then consider shaping the culture you exist in, to whatever extent you can. If recent events have shown anything, it's that the paeans to the joys of intellectual diversity in who you associate with or tolerate are only sung when you hang out with the right people, and only until someone feels an adequate tipping point has been reached.