sounds like a bit of mental masturbation, but I think it really is an important question, because we now have a discourse in which “everyone is entitled to their opinion” and “that’s just my opinion” being used as a shield against criticisms, and said criticisms of people’s “opinions” being variously titled anti-democratic, elitist, bigoted, et cetera. As such, if we want a functional conversation about pretty much anything, it actually matters what the word “opinion” means, and what it actually means to have the right to an opinion and all opinions being valid and equal.
At the most basic level, “opinion” is an expression of personal taste. I can be of the opinion that green is the prettiest color, that Johnny Depp is sexy, that Meryl Streep is a great actress, that white chocolate is nasty, that both Ulysses and Twilight are unreadable crap, etc. and it’s very hard to argue against me having a right to such opinions. Or even that such opinions are more or less valuable and correct than others, without running into issues of classism that usually accompany the judgments of tastes as high-brow, middle-brow, and low-brow. Sure, a better understanding of Jazz and modern art and coffee brewing might make me more appreciative of these things, even leading to liking it more; but not always (I understand Jackson Pollock’s art just fine; it’s still mindnumbingly boring to look at), and nor is such a refined liking objectively more accurate or more valid. My liking of Punk is not objectively worse or less accurate than someone’s liking of Jazz, and probably the sole exception to this is when the issue is one of communicating outwards, at which point pinpointing your audience’s tastes and opinions accurately is more important than your own personal tastes, and (mis)communicating in this way might well be better or worse, more accurate or less so.
At the second level, we have normative opinions. This is where it gets a bit trickier, since there are two kinds of normative opinions, and they can bleed into each other easily. The first kind is wishful thinking, and I daresay it’s impossible to reasonably claim that one kind of wishful thinking is more accurate or valid than another. However, the second kind of normative opinions is actually normative, in the sense of desiring to make something the social norm. At this point, the opinion leaves the realm of tastes and personal preferences and begins to touch on external reality, and it’s the degree to which it does so that determines whether a judgment about it’s validity and accurateness can be made. For example, if you wished that no one ever got their heart broken, that’s sort of an interesting but inarguable personal fantasy; but if you wish to create a world in which no one ever gets their heart broken… then yes, I can accuse you of being disconnected with reality, and I have the right to criticize such an “opinion” for the ways in which it conflicts with what is actually possible, for the ways in which the methods you suggest are likely to backfire, etc. Unfortunately, people rarely distinguish between wishful thinking and desire for social change, and interpret the criticism of the latter as criticism of the former.
Beyond this level, “opinions” start becoming more and more like truth claims rather than personal preferences and tastes. And the more they do so, the more criticizable they become. But as long as people keep on referring to them as “opinions”, and thus equating them with statements of personal taste, we will continue hearing about how elitist and bigoted it is to criticize people for their opinions. It’s that conflation that memorable quotes such as “you’re entitled to your opinion, but not your won facts” and Asimov’s awesome comment against anti-intellectualism* argue against. Most obviously, scientific questions about whether evolution is happening, or whether AGW is happening, are simply not ever, by any actual definition of the word, “opinions”. The answers to questions about how the world is or how it works are factual questions with generally only one correct answer. And just because even science can only approximate that correct answer as it learns more an more about the world and eliminates the incorrect answers**, you can’t just go all uber-relativist and decide that reality is a matter of personal preference. And, to go on a little tangent here, this is true as much for questions of climate science and biology as it is for questions about faith and religion: claims about gods are truth claims as much subject to science and as much not-opinions as claims about AGW, the efficacy of vaccines, and the existence of the Yeti are.
I would like, however, to also point out that shoving “politics” into the realm of opinion is equally incorrect; and dangerous. Yes, the science gets messier the closer we get to humans; yes, the democratic ideal means that everyone has a right to have their voice heard as part of self governance, and that a person should have the right to be part of decision-making in reasonable proportion to how much such a decision will affect them. But it’s because of this, not despite this, that we really need to accept that political positions simply aren’t like arguing over the best flavor of ice-cream; and it’s because of this, not despite this, that we need to value the science that we do have, because it helps us actually make the decisions that will lead to the goals we have. In other words, to have a functioning, democratic(-ish) government, we need a culture that treats politics as a science rather than as personal preference*** or as a matter of group identity. What this would mean is that people, as they participate in self-governance, would feel entitled to and understand the value of expert opinion in very much the same way we still value the expert opinions of doctors and demand the right to be informed by them as much as possible while reserving the right to ultimately make the relevant decisions ourselves(see: informed consent).
Point being: while everyone is entitled to an opinion, and taste is a personal, relative, and subjective matter, most things people label with that word are actually truth-claims, not opinions at all. And for those things, these rules don’t apply; not all truth-claims are equally valid and true, and you’re not entitled to your own facts, even if you call them opinions.
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*“Anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that ‘my ignorance is just as good as your knowledge.’”
**see also: post-positivism and falsification (as opposed to making shit up, and also as opposed to positivism and verification)
***if you have a culture that manages to treat science as a matter of personal preference, you’re fucked. Somewhat unsurprisingly, that seems to be where the slippery slope of “x is an opinion” actually, demonstrably leads. Which I suppose is another argument why one should fight back already at the level of politics being seen as a matter of opinion, because it apparently won’t stop there.