Facts and Opinions are not Contraries
“Fact vs opinion” is not like “hot vs cold” or “fast vs slow”. Facts and opinions are different kinds of things.
I teach philosophy to undergraduate students, mostly freshman and sophomores, at UCLA. I’ve been puzzled and slightly disturbed by a recurring idea that some of them seem to take for granted. This is the idea that claims about (say) what would be just, or what we ought to do, are merely matters of opinion. I call this disturbing not just because of the dubious implication of relativism, but also because this way of thinking involves a fallacy.
The same problematic idea is implicit in the question, “Is that a fact, or just your opinion?” The problem is that the question presupposes that facts and opinions are contraries like hot and cold, or fast and slow. This is what’s called a “category mistake”. Category mistakes are a kind of logical fallacy. So, if I’m right, then any reasoning that relies on this contrast is fallacious. We would think better if we eliminated this way of reasoning.
Quite a lot has been written on the fact/opinion distinction. Much of it is by educators interested in helping students to think critically—certainly a noble goal. However, the vast majority of this material is too sloppy to be helpful, mainly because it plays fast and loose with multiple distinctions. (There is some good stuff too, of course. See here, here, and here.)
A classic illustration of a category mistake is the sentence “Colorless, green ideas sleep furiously.” While this sentence is grammatically correct, it’s meaningless. Ideas aren’t the sort of thing that can have a color or go to sleep. Colored objects and ideas are just different kinds of things. Similarly, I claim that facts and opinions are different kinds of things. Facts are metaphysical entities, while opinions are epistemic ones. (I’ll explain what that means below.)
If facts and opinions are different kinds of things, then they can’t be contrary to each other. Hot and cold are both approximate measurements of temperature. Fast and slow are both approximate measurements of velocity. If they weren’t, then they couldn’t be opposites. My claim is that facts and opinions cannot be contrary to each other for this same reason. Asking if some claim expresses a fact or an opinion is like asking whether some object is hot or slow. It could be both! It could also be neither!
So, what do I mean by “metaphysical” and “epistemic” entities?
Metaphysical entities are things in the world. They may be physical things: atoms, planets, rocks, etc. Or, if you believe in such things, they could be non-physical objects. They could be abstract objects like numbers, or supernatural objects like gods or souls. So, to say that a fact is a metaphysical entity is to say that it’s a thing in the world. More specifically, facts are states of affairs. If it rains tomorrow, then it’s a fact that it will rain tomorrow. The sentence, “It will rain tomorrow” expresses a fact just in case it does rain tomorrow.
Epistemic entities, on the other hand, are matters of belief and/or knowledge. Epistemology is the study of knowledge. (“Episteme” is the Greek word for knowledge; the “ology” suffix means “the study of”.) So when I say that opinions are epistemic entities, what I’m claiming is that opinions are a certain kind of belief.
Notice that, while it could be a fact that it will rain tomorrow, even if no one believes it, it could not be the case that it is an opinion that it will rain tomorrow, even if no one believes it. An opinion is always some person’s opinion. A fact, on the other hand, can exist even if no one knows about it, or even if nobody existed to believe anything at all. Indeed, in such a case, it would be a fact that there are no people around to have opinions.
I take it that what distinguishes opinions from other kinds of beliefs is something like one’s confidence in the truth of the claim, or the kind of evidence upon which the claim is believed. Suppose that I come to believe that it will rain tomorrow on the basis of weather.com’s forecast. They suggest 90% chance of rain. It would seems strange to say that my belief that it will rain tomorrow is just an opinion. Of course, I could be wrong. But, I can (and should) be fairly certain about it raining tomorrow. Suppose, however, that the forecast is a 50% chance of rain. If I still believe that it will rain, it now feels more appropriate to call my belief an opinion. I shouldn’t be too confident in that belief. Similarly, imagine that I come to believe that it will rain tomorrow because I have performed a rain-inducing religious ritual. Clearly, in this case, my belief would be called an opinion (or else something less polite). The point here is that opinions are a special kind of belief — specifically, beliefs held either on the basis of uncertain evidence or an unreliable form of evidence, the sort of beliefs that a rational person could doubt.
Let’s tie all this together. What would have to be the case for the sentence, “It will rain tomorrow”, to express a fact? As we saw, it would have to rain tomorrow. What would have to be the case for “It will rain tomorrow” to express an opinion? (Since an opinion is necessarily someone’s opinion, let’s say it’s my opinion.) I would have to believe the sentence on the basis of some not entirely certain or not entirely reliable evidence. It should be clear, then, that the sentence could express both a fact and an opinion.
Here’s one scenario in which it would: I do a rain dance, conclude that the gods have heard my prayer, and so come to believe that it will rain tomorrow. It does rain tomorrow. Since I believed that it would rain the next day on the basis of an unreliable form of evidence, my belief that it would rain was an opinion. That it did rain means that it was a fact that it would rain. Therefore, “It will rain tomorrow” expressed both an opinion and a fact. The conditions for expressing a fact and expressing an opinion are not exclusive of each other.
Another way of putting my point is that that facts are reality, the way that things are. And opinions are (not entirely certain, or somehow disputable) beliefs about that reality.
So, rather than asking, “Is that a fact, or just your opinion?” you should ask, “How confident are you in that belief?” or, “Upon what evidence have you come to this conclusion?” Not only do these questions avoid the fallacy of category error, they also prevent people from using the label of “opinion” to divert attention from our reasons for belief. People often say something like, “That’s just your opinion” as a conversation stopper. This is a kind of rhetorical bullying. It’s a way of avoiding an actual evaluation of the evidence and arguments for the competing views.
This is especially important when there is something of ethical importance at stake. Should we send troops to Iraq or not? Should women be allowed to have abortions or not? Denigrating a person’s views on these questions by calling them “opinions” doesn’t help us decide what to do. Worse, it distracts us from the relevant considerations in favor of each option. Clear thinking is valuable in itself. But, it’s especially important when so much is at stake.
