My point was that some animals do appear to be able to be rational, to a degree. (I'm defining 'rational' as something like 'able to create accurate representations of how the world works, which can be used to make accurate predictions.)
I can even come up with examples of some animals being able to be more rational than some humans. I used to work in a nursing home, and one of the residents there was mentally retarded as part of her condition, and never did figure out that the cats could not understand her when she talked to them, and sometimes seemed to actually expect them to talk. On the other hand, most animals that have been raised around humans seem to have a pretty reasonable grasp on what we can and can't understand of their forms of communication. Unfortunately, most of my data for the last assertion there is personal observation. The bias against even considering that animals could communicate intentionally is strong enough in modern society that it's rarely studied at all, as far as I know. Still, consider the behavior of not-formally-trained domesticated animals that you've known, compared to feral examples of the same species.
Basic prediction-ability seems like such a universally useful skill that I'd be pretty surprised if we didn't find it in at least a minimal form in any creature with a brain. It may not look like it does in humans, in those cases, but then, given what's been discussed about possible minds, that shouldn't be too much of a problem.
The bias against even considering that animals could communicate intentionally is strong enough in modern society that it's rarely studied at all, as far as I know.
Animals obviously communicate with one another. The last I heard, there was a lot of studying being done on dolphins and whales. Anyone who has trained a dog in anything can tell you that dogs can "learn" English words. The record I remember hearing about was a Border Collie with a vocabulary of over 100 words. (No reference, sorry. It was in a trivia book.)
As for your point, I...
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.