What quick-and-easy rules of thumb to gauge how rational someone else is do you tend to use? How accurate do you think those rules are, and can you think of any way they might be improved?
For some examples of what I mean, one of the benchmarks I use is the basic skeptics' list: astrology, chiropractic, little green men abducting cattle and performing anal probes, Nessie. Another is the denialist checklist: holocaust denial, moon landing denial, global warming denial. Another is supernaturalism in general: creationism, intercessory prayer, magick, psychics, curses, ghosts, and such. If I find out that anyone I know believes in any of that, then my estimation of how well they can consider things rationally goes down. Theism... well, I've gotten used to pretty much everyone around me being theistic, so that's kind of the baseline I assume; when I learn someone is an atheist, my estimation of their rationality tends to go /up/.
Do you have any items which make you think someone is even further along the path of rationality than simply not believing logical fallacies?