Here's one that many people understand but some don't.
On subjects in which you personally are not a Ph.D. level expert, attempting to evaluate object-level arguments will generally lead you astray, because some people are really, really good at sounding convincing. The best you can do is to simply accept the majority view of the experts in the age in which you live; if their arguments really were as convincing as they seem, then the experts would probably have accepted them.
On the other hand, choosing the right experts is a huge problem in and of itself.
On the other hand, choosing the right experts is a huge problem in and of itself.
Eh, choosing people who have academic credentials (from major establishments) in the topic in question should bring you close enough to the truth (or at least, as close as you can be without putting in at least as much work as they did). Sure, you'll get it wrong sometimes (listening to theologians on religion), but it's likely to be more correct than trusting your own judgement, or than trusting experts from the wrong domain (physicists talking about diet, biologists talking about cosmology, science fiction authors talking about consciousness, etc.).
I was just wondering. Human minds are messed up in 1001 ways, but are there a few rational principles that most people already have down? Of course, the answers to this question are probably so extremely obvious that I haven't even considered them. But I ask all the same.