Out of curiosity, can someone who does not have a grain of rationality in them ever become more rational?
They may stumble across rationality as life causes their core functions to randomly vary. As far as I can tell, that's how explicit and self-referential standards of thought first arose - they seem to have occurred in societies where there were many different ideas and claims being made about everything, and people needed a way to sift through the rich bed of assertions.
So complex and mutually-incompatible cultural fluxes seem to not only be necessary to produce the first correct standards, but encourage them to be developed as well. That argument applies more to societies than individuals, but I think a similar one holds there too.
Short answer: only by chance, I think.
Short answer: only by chance, I think.
Understood. I guess the followup question is about where the general human being starts. Do we start with any rationality in us? My guess is that it is somewhat random. Some do; some do not.
A currently existing social norm basically says that everyone has the right to an opinion on anything, no matter how little they happen to know about the subject.
But what if we had a social norm saying that by default, people do not have the right to an opinion on anything? To earn such a right, they ought to have familiarized themselves on the topic. The familiarization wouldn't necessarily have to be anything very deep, but on the topic of e.g. controversial political issues, they'd have to have read at least a few books' worth of material discussing the question (preferrably material from both sides of the political fence). In scientific questions where one needed more advanced knowledge, you ought to at least have studied the field somewhat. Extensive personal experience on a subject would also be a way to become qualified, even if you hadn't studied the issue academically.
The purpose of this would be to enforce epistemic hygiene. Conversations on things such as public policy are frequently overwhelmed by loud declarations of opinion from people who, quite honestly, don't know anything on the subject they have a strong opinion on. If we had in place a social norm demanding an adequate amount of background knowledge on the topic before anyone voiced an opinion they expected to be taken seriously, the signal/noise ratio might be somewhat improved. This kind of a social norm does seem to already be somewhat in place in many scientific communities, but it'd do good to spread it to the general public.
At the same time, there are several caveats. As I am myself a strong advocate on freedom of speech, I find it important to note that this must remain a *social* norm, not a government-advocated one or anything that is in any way codified into law. Also, the standards must not be set *too* high - even amateurs should be able to engage in the conversation, provided that they know at least the basics. Likewise, one must be careful that the principle isn't abused, with "you don't have a right to have an opinion on this" being a generic argument used to dismiss any opposing claims.