Here are some claims that I am inclined to think true, and that I'm inclined, even after reflection, to think that I have justification or warrant for. In one or two cases, though, there may be some doubt about what is actually meant, let alone whether the claim is really true. Let's have a look:
"Right now, as I type this, the sun is shining outside my window."
"Macbeth is the main character in Macbeth."
"In Macbeth, Macbeth murders Duncan."
"Macbeth is a tragic hero."
"Macbeth loves Lady Macbeth, at least at the start of Macbeth."
"As I type, the US and Australian dollars are roughly at parity."
"Human reproductive cloning is illegal in Australia."
"I had spaghetti for lunch yesterday."
"Cheetahs are beautiful animals."
"Medellín was once racked by political instability and guerilla warfare."
"Maxwell Perkins was a great editor with a superb (if not unerring) ear for literature."
I've stolen the last couple of these, with minor modifications for concision and to make sure I think they are true, from Jerry Coyne's blog.
The first point I want to make about all the above is that, if I actually know these things to be true, it's not through science. My claim isn't necessarily that they are science defeaters, as if scientists are helpless to find out these sorts of things. I simply say that it wasn't through any distinctively scientific process that I found out any of the above. Nor did I find out these things by asking someone who did use a distinctively scientific process (or who in turn ... etc.). These are all things of a kind that could have been found out long before the methods that are distinctive of science coalesced into the beginnings of the institution or practice that we now know as science. Of course, we couldn't have known that human reproductive cloning was illegal, back in those days, because without science such a thing would not even make sense as something to ban. But we could certainly have consulted statute books, lawyers, and so on about various matters of law.
Nor could I have found out that it is illegal by looking it up on the internet ... not without the technoscience that makes the internet possible. But if I just go and look on a site like AustLII I am not doing anything distinctively scientific. I'm just doing the equivalent of reading a statute book, which could have been done in medieval times.
Whether there are some things that are, in principle, always going to be science defeaters is another thing. I don't make that claim and I'm not sure how exactly it could be settled. But I do, for example, claim that it would be impractical and unnecessary to try to use any distinctively scientific activities to find out whether or not Macbeth really is the main character of Macbeth. Just read the text or go and watch a production, and you'll come to that conclusion. Or ask someone who is trustworthy on such things.
But be warned, once you start drawing conclusions about Macbeth that go beyond the least sophisticated ("Macbeth is the main character of Macbeth"), you may need quite a bit of education in the English of the time, in the historical context, in the literary forms that had existed up until then, and so on. It's possible to pick that up in various ways, but there's a lot to be said for actual guided and formalised study with teachers who know what they're talking about.
Some of the other claims I've made are trickier: e.g. is it really true that cheetahs are beautiful animals?
Well, they sure look it to me. But there's still a nagging question about whether cheetahs are really beautiful and what the claim even means. Does it just mean that they have (perhaps unspecified) characteristics that strike "us" (whoever "we" are in this context) in a certain "aesthetic" way - or what? Some people may believe that cheetahs possess a rather spooky property of strongly objective beauty such that any rational being in the universe somehow makes an error about reality if it fails to see a cheetah as beautiful. I doubt, though, that many of us really think anything like that, even if people in some culturally-closed societies (and perhaps not just them) have thought that way.
Note that science may be able to do a great deal to clarify how many people really see cheetahs as beautiful, what is going on at the level of the functioning of the brain, what it is about cheetahs that produces these responses, etc. I'm not at all claiming that science has nothing to say about the beauty of cheetahs, or, indeed, about any of the issues raised by the statements I listed above. Still, these are all things that are known to me, if they really do constitute knowledge, with nothing distinctively scientific being involved in the way I found out.
I keep talking about "distinctively scientific", because I am well aware that scientists are able to look outside and see whether the sun is shining or whether it's a cloudy day. Or they can use indirect methods of various kinds to infer, "The sun is currently shining in Newcastle, Australia." However, I don't rely on anything especially scientific; I just look out the window.
Obviously I am talking about "science" in a sense that is narrower than "rational inquiry" (I'm prepared to assume that looking out the window is, or can be, an example of rational inquiry). As usual, I can't give you a precise definition. I don't think that phenomena such as science lend themselves to sharp definitions; they are inherently fuzzy, as are many of our concepts. However, it is possible to have a fairly rich conception of science that definitely covers some things and not others. For example, if I simply read Macbeth I am definitely not doing science in the sense under discussion. If I'm trying to work out stuff about the play as I read it (Who is the main character? Could it be Macbeth?), I am engaging in a form of rational inquiry, but it's a humanistic form of rational inquiry, not a distinctively scientific form. On the other hand, it seems to me that these can merge into each other. For example, humanistic scholars are quite capable of using more distinctively scientific approaches on occasion - computerised word frequency analyses provide one example where a scientific instrument is being used by textual scholars to assist with humanistic research. And of course, scientists can read texts, watch plays, learn languages and so on. No one has a monopoly on any of this.
I object to the expression "other ways of knowing" because people who use it tend to countenance methods, such as divine revelation and mystical insight, that seem to me to be pretty damn dubious as ways of finding out stuff. But there are obviously many things I can do to find stuff out - e.g. I can just go and look, in some cases, or read a novel in others, or rely on my memory. Scientists rely on a mix of these things as does everyone else. But not everyone else puts so much emphasis on studying phenomena that are very small, very ancient, or very distant, or using theoretical propositions about these phenomena as causal explanations, and not everyone else relies so heavily on such things as mathematical models, controlled experiments and hypothetico-deductive reasoning, and scientific instruments.
I view science as a distinctive phenomenon that arose in a recognisable form around the start of the seventeenth century, though of course it had precursors. Seventeenth-century thinkers realised that they were confronted by something new and powerful, though they did not invent the word "scientist" (that came much later).
The thing about science is that it's continuous with rational inquiry more generally. We need a word for the phenomenon that I've sketched in the last couple of paras, and "science" is the word we've inherited. So I prefer not to use the word to mean simply "rational inquiry" and I think there's at least some fuzziness about, for instance, whether what we call political science is really best classified as science (usually, in fact, it isn't for pedagogical purposes). The main thing, however, is to make sure that we're consistent in any given context as to how we conceive of science and use the word "science". As so often, we'll create confusion if we use the word in two or more diffferent ways in the same discussion, or within the same argument.
Now, I don't accuse Jerry Coyne of doing that over here. He makes clear that he is using a broad conception of science while I am using a narrow one. It follows that we are not necessarily disagreeing with each other on anything.
But if we're not all careful to define our terms - or at least give some indication of how broad our concepts are - we run quickly into the possibility of confusion. Let's all tread carefully here. Oh, and it might be a good idea to apply the principle of charity and assume that our interlocutors are not saying weird or extreme things.