Anybody who rejects the hypothesis that some tribal group to which they belong is how the truth is discovered and defined, and accepts the reality that it must be investigated without reference to the narratives and worldviews of said tribal groups including their own, is capable of parsing the truth. They might not arrive at the right result, but they're at least capable.
If a person can't do that though, then they're not even trying to parse the truth, they're just engaging in tribal in-group signalling with their peers, which as far as I can see is the vast majority of what humans do to the exclusion of all else. The supermajority of humanity waving red or blue flags and shouting their slogans hasn't sat down and actually analysed any of the underlying issues, that's not what their displays are about.
Maybe I'm wrong, but that's always the way its seemed to me, I've never witnessed that tribal in-group signaling being subject to any kind of critical analysis whatsoever, and any attempt to engage in such isn't seen as an attempt to find out what's true, but an attack on their tribe.
This isn't even limited to the more popular tribal in-groups. I am certain that you could find an Alex Jones infowars type who, if you sat down and earnestly attempted to engage in a dialogue with them about some belief they held that you could prove outright empirically was false, they would not view that dialogue as a mechanism for finding the truth, but once again, an attack on their tribe. This just seems to be the way the vast majority of humans work, and it kind of makes sense in a context of collectives engaged in constant struggle against each other for dominance in brutal and messy ways.
Nuanced views are a luxury few can afford, and a neat way to end up outcast and subject to the depredations of any of the aforementioned dominant aggressive collectives. Before you know it, they're forcing you to drink Hemlock.
