disillusioned

Since @WalterP brought it up, and since it has direct bearing on the main topics of this thread, I want to spend a bit more time exploring the connections between Hume’s matters of fact and relations of ideas, and my ontological and epistemic truths, and the connections that all of these ideas have to science. Hume’s notion of “relations of ideas” corresponds roughly to our knowledge of statements which are logically necessary. Mathematical truths, such as “3+2=5”, and tautological sentences such as “all bachelors are unmarried” are typical examples of relations of ideas. Such things cannot be asserted to be false without giving rise to contradictions. As such, we may claim a priori knowledge of these types of claims. By contrast, matters of fact concern knowledge that we gain from experience. That the sun rose this morning is a matter of fact, as is the fact that it set last night. Matters of fact cannot be shown to be true or false using pure reason; experience is necessary. Moreover, denial of a matter of fact need not lead to a logical contradiction. If you say it is day, I can say it is night. One of us is wrong, but either way, there is no huge logical crisis. We can only know who is right through experience. Thus, we may only claim a posteriori knowledge of these types of claims. There is a clear similarity, I think, between my notion of ontological truth and Hume’s notion of matters of fact. Both are clearly referring to the natural world, in general. There is an important difference though: matters of fact are what I would refer to as knowledge claims which are often about ontological truths. They are not ontological truths themselves. On my view, there are some things which are actually ontologically true. Real brute facts about the world. The problem is, whenever we try to give examples of such things, we can only speak from our experiences. So when I say “the earth is round”, or even “granite is hard”, I am making an ontological truth claim, and my contention is that I know that each of these statements is actually ontologically true. This is roughly equivalent to saying that I claim each thing to be a “matter of fact”. Notice, however, that my claim to know that each statement is true does not in any way necessitate that it actually is. The history of science is littered with things that people used to know, which we know to be incorrect. This does not necessarily mean that any ontological truths have changed. Knowledge claims, on my account, concern what we believe about ontological truths. So it isn’t quite correct to draw a direct equivalence between matters of fact and ontological truths. Rather, matters of fact are knowledge claims. They are often about ontological truths, but they don’t always have to be, as I’ll explain in a moment, and they are not ontological truths themselves. Relations of ideas, on the other hand, are most similar to what I have called formal truths. Recall that I am treating formal truths as a subset of epistemic truths. Formal truths can actually be shown to be true logically and necessarily (using a formal language if required). Relations of ideas seem to me to be basically the same as this. These are things which are either true by definition (for example, “all bachelors are unmarried”) or which follow directly deductively from axioms (for example, “3+2=5”). Thus, relations of ideas concern a type of epistemic truth, namely, formal truth, but I do not think that they account for all epistemic truths. Take the case of the statement “money is valuable”. This is an epistemically true statement. However, our knowledge that it is true comes from experience. Thus, when we claim to know that money is valuable, we are claiming this to be a matter of fact. What I think is really interesting here is that the truth of the statement “money is valuable” derives from our knowledge that money is valuable (this is what it means for it to be epistemically true), but our knowledge of the truth of the statement “money is valuable” derives from experience (when we try to use money, we find that it has value). Each experience of money’s value reinforces our belief that money is valuable, and we end up in a self-reinforcing cycle. This is not a problem logically, because no one is claiming that it is necessarily true that money is valuable. It just happens to be the case. It’s a matter of fact, but it’s a matter of fact which corresponds to an epistemic truth. This is another reason why I think we can’t draw a direct line between Hume’s matters of fact and my ontological truths. Some matters of fact refer to epistemic truths. Alright, now back to science for a moment. When we do science, it seems to me to be fairly clear that we are reasoning on the basis of observation and experience. Thus, scientific knowledge is a posteriori in nature. Science aims at matters of fact. Where things get murky is that when we move into more sophisticated science, we end up building (sometimes formal) models which we then use to make predictions about what we should see. We begin to reason inductively. On the basis of what we have observed, together with some assumptions, we make predictions about we expect to observe. This is the essence of inductive reasoning. Hume is famous for pointing out that there is a problem with induction: we have no logical reason for thinking that our experiences of the past should be representative of the future. It simply doesn’t follow that because the sun has risen every morning of my life, it will therefore rise tomorrow. Nevertheless, we all feel fairly confident in claiming to know that it will. This is a very famous philosophical problem which we can spend some more time looking at if it is of interest, but for now I just want to say that I think this is basically correct, but it isn’t really a problem. We can’t help but reason inductively. It’s the only card we’ve got to play. And it seems to work pretty damn well, so we carry on. Where scientists sometimes run into trouble is when they lose track of the fact that things which have been shown to be true on a particular model are not necessarily actually ontologically true. The Hawking-Penrose theorems are good examples here. These are formal truths (ie, relations of ideas), but the model under which they are provable is out-dated. So they can’t be said to be matters of fact, let alone to actually be ontologically true. This is where WLC makes one of his many fatal errors. There is a lot more that can be said about this, but that’s probably enough for one post.

Walter, Thanks for a very thorough and interesting couple of posts. I just have a few brief remarks for now, but I will have more to say over the next few days. This seems like an interesting book. I might need to give it a read. This particular passage makes mention, among othe things, of Hume's distinction between matters of fact and relations of ideas. If I recall correctly, it was Hume's writings on these (and other) topics that played a key role in inspiring Kant to formulate some of his most crucial ideas. In particular, it seems to me that there are stong parallels between Hume's "relations of ideas" and Kant's "analytic judgements" as well as between Hume's "matters of fact" and Kant's "synthetic judgements". Kant and Hume are both philosophers for whom I have a great deal of respect, even if I am still only barely beginning to scratch at the surface of their ideas. One thing that is interesting to me at the moment is that it seems that both Kant and Hume, as I currently understand them, tried to ground philosophy in epistemology rather than ontology. I think these things go hand in hand, but ontology comes first. This is why I start with basic assumptions about nature, use these to formulate an idea of truth, and try to build a concept of knowledge from there. I have more to say about this, but I'm pressed for time at the moment, so I'll have to come back to it. This is an excellent quotation, and it clearly illustrates one of the reasons why I'm a great admirer of Hume. Descartes, I think, for all his brilliance, made a number of critical errors, and Hume went a long way towards correcting some of those errors. Agreed. I want to look more at the relationship between Hume's 'matters of fact' and my 'ontological truths' , as well as what you've pointed out here about the H-P theorems, and the larger issue of formal truths in general, and their relation to science. I'm hoping I'll be able to get around to writing a more rigorous response in the next few days.

I want to say that I agree with some of the sentiments expressed, but I'm not sure I can say even that. It isn't at all clear to me what he means by "believe", "know", and "perceive". I think there may be something to what he is trying to say, but I'm afraid I just don't know exactly what it is that he's trying to say. What I've been trying to do in this thread is establish clarity in my use of terms like belief, knowledge, and truth, so that I can develop some ideas about these things in a coherent fashion. In doing this, I've been taking an axiomatic approach, which is to say that I've been arguing on the basis of assumptions. The gentleman in the video seems to think that assumptions are barriers to knowledge, and that belief is blind necessarily. This clearly conflicts with what I've argued this far, which is fine in itself; I'm happy to look at alternative views. The problem is that I just don't know what exactly he's trying to say. So I can't actually consider his view, because I just don't know what it is. Can you offer any clarity here @Karna?

I made mention of formal truth in a previous post, and said that I think it is a type of epistemic truth. I'd like to return to this idea now and be a bit more clear about what I mean by this. Formal truth is generally taken to refer to logical or mathematical truth. These truths can be shown to follow directly, via deduction, from a well-defined set of axioms. That is to say, formal truths are actually provable. On standard arithmetic, that 2+5=7 is a formal truth. That the angles in a triangle add up to 180 degrees is a formal truth on Euclidean geometry. Other examples can be given, but I want to look at these two for now. I want to explain why I think of formal truth as a type of epistemic truth, and not a type of ontological truth. It's very tempting to say 2+5=7, for example, is just a brute fact, that it's true irrespective of what we think, and is therefore an ontological truth, but I think this is incorrect. The reason why I think that this is incorrect is that "2", "5", and "7" are not material objects. They are ideas. Moreover, the rules of arithmetic are a human construction, and they don't have to be as they are. On addition modulo 6, for example, 2+5=1. It's possible to do this type of addition over a field which doesn't contain 7 at all (ie, a field in which 7 is not a thing). For the record, this is something that mathematicians actually do, and it does have real applications. So it does not have to be the case that 2+5=7. It is the case because of our conception of the numbers involved, and our definition of the rules of arithmetic. But this is how epistemic truth works. The triangle example also breaks down as a matter of ontological truth. Ideal Euclidean triangles do not exist in the real world. All real-world triangles are approximations. Moreover, triangles which are drawn on the surface of the Earth violate this rule altogether, because the surface of the Earth is not flat. The axioms of Euclidean geometry, like the rules of arithmetic, are a human construction. They can be used to generate quite a lot of truths, but these truths rest on human thought, which is to say they are epistemic. Now, it is very important to note that I am not saying that we can't reason formally about ontologically objective objects. We certainly can. Scientists do this all the time. It may even be the case that we can establish a formal truth which gives us knowledge of an ontological truth. But we can't generate ontological truth through formal reasoning. What we generate is epistemic truth. That is the point. We can reason formally about the natural world, and in so doing, build scientific models which establish formal truths. This may lead us to claim knowledge of ontological truths, but we need to keep in mind that our knowledge of these kinds of truths is really just firmly held belief. By contrast, when we establish formal truth, we don't merely establish knowledge of a truth, we actually establish the truth itself. I say that I know the earth is round, but I say it is true that 2+5=7 (on the usual rules, etcetera). This is an important difference. I think that one of the things that science does is build models of the universe. The models have rules and laws. When a particular model becomes well-established and generally accepted, it becomes very tempting to start treating the laws of that model as actual laws of the universe. I think this is a fundamental mistake. What we typically call laws of the universe are actually laws of our models of the universe. Where their truth has been established, it has been established epistemically. It must be this way. This is not to say that we can’t have knowledge about ontological truth, just that we can’t have absolute certainty.

My answer to this is "false". From science, we have knowledge which contadicts this claim. That is to say, science leads us to strongly believe, on the basis of a lot of evidence, that this statement is ontologically false. Remember, science attempts to get at ontological truth. It does this via epistemic models, so it doesn't lead to ontological truth directly, but that is not to say that it can't give us knowledge of ontological truth; it's just that our knowledge is never 100% certain. But that's true of basically all knowledge on my account, so it isn't particularly troubling. I agree with this. Some people might even say that something like this could be taken to be your personal truth. I generally find such statements to be silly. Certainly it is possible to believe the claim, but belief doesn't entail truth. Even knowledge doesn't necessarily entail truth on my account. With this particular claim, I have a hard time seeing how it could be said to be epistemically true at all, because it is fundamentally an ontological claim. As such, what we think about it is not supposed to matter. And our best scientific evidence contradicts the claim, which is why I say I know it is false. Yes, I agree with this. I think it's just bad reasoning, to be honest. This is good, and it's one of the reasons why I made this thread. A theory of truth is no good if we can't apply it to actual examples. I'm hoping to be able to look at how this applies to lots of things as we go forward.

Walter, I think the overarching question of how science fits in with the account that I've given so far is extremely important. I'm going to try to sketch an answer to this question briefly before I address the specific questions you raised in your post. I hope that it is fairly clear that science is a human endeavour. It's a process which aims to generate knowledge about the natural world. That is, it aims to generate knowledge of (primarily) ontological truths. Notice, immediately, that I do not say that science generates ontological truth. What it generates is knowledge. Because of science, we know that the Earth revolves around the sun, that water boils at 100 degrees Celsius at standard atmospheric pressure, and that light bends away from the normal when it passes from a dense medium into one that is less dense. Now, the crucial point is this: it is very tempting to say that science has established the truth of these statements, but I think that this is incorrect. What science has done is establish our knowledge of these things. We know these things, which is to say that we are quite sure that they are true. But we are not certain. We can never be certain. Recall that on my account, knowledge reduces to firmly held belief. I have no qualms about saying that I know that the Earth revolves around the sun. There's all kinds of good, scientific evidence to support this belief. So it is very well justified. But it's still just a firmly held belief. I think it has to be this way. Suppose for the moment that it actually is ontologically true that the Earth revolves around the sun. What this means is that it needs to be true regardless of our knowledge of it's truth. Moreover, it would also need to have been true in previous eras, when basically everyone who knew anything knew that the sun revolved around the Earth. Tycho Brahe was a pretty serious scientist, but he managed to produce what we now know to be a more or less entirely incorrect model of the solar system. This seems to entail exactly what I've been arguing so far: that science produces knowledge, but not necessarily truth, and also, that today's knowledge is quite often tomorrow's misapprehension. So where does this leave us? Well, we've seen that science generates knowledge of ontological truth, but we haven't looked in detail at how it does this. And this is where I think things get really interesting. Previously on these boards I've written that I think science offers epistemically objective descriptions of an ontologically objective reality. What I mean by this is that science builds models of the universe. The models make all kinds of ontological truth claims, because they are attempts to describe the natural world. But the models themselves are constructed by humans. They operate according to assumptions we make, and lead to conclusions which are based on both observation and inference. I think it is correct to say that the models can establish formal truth, which I view as a kind of epistemic truth (there's quite a bit more that I want to say about formal truth as a type of epistemic truth, but I think it's tangential for now, so I'll come back to it later if it is of interest), but they do not establish ontological truth. Take, for example, the Hawking-Penrose Theorems. On their assumptions, it follows logically that the universe began in a singularity. So on their model, it is formally true that the universe began in a singularity. It's mathematically provable. The problem is, their model doesn't fit the observational data, so something is wrong with their assumptions. It doesn't seem to be ontologically true that the universe began in a singularity. Nevertheless, whether it did or not is a matter of ontological truth. Hawking and Penrose offered a particular model, and on that model it was true. And for a while, everyone knew that the universe began to exist. Nowadays, we can't really claim to know this anymore, because the model that Hawking and Penrose offered is outdated. This is what science does all the time. It builds models of the universe which establish formal (read: epistemic) truths. It's very easy to confuse these with ontological truths, but that is a disastrous mistake, on my view. Neils Bohr said that "It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we say about Nature." I think this is basically the same thing that I'm trying to say: physics, and science in general, concerns our knowledge, not truth per se. Where science does concern truth directly, the truth in question is formal, or epistemic, rather than ontological in nature. There's a lot more that can be said about this, but for now I want to move to the questions you actually asked. I hope that what I wrote above clarifies this somewhat. I think that science in general can generate ontological knowledge, but it's important to note that knowledge is not certain. For fields of science like astronomy and cosmology which rely more heavily on assumption and inference than do some other fields, our level of certainty in the ontological knowledge we obtain must be lessened. This is why I tend to take novel cosmological theories with rather large grains of salt. What I would say is that there is clearly a realm which is directly accessible to our senses, and this allows us to claim ontological knowledge about this realm with much more surety than we can claim such knowledge about cosmology, for example. I can claim with quite a lot of certainty that granite is hard. For all intents and purposes, I know this for sure. I can directly verify it. The only thing keeping me from claiming direct access to ontological truth in this case is the possibility that I might not be able to trust my senses. But on the assumption that I can (which seems reasonable), it follows that granite is hard. So I know this with much more certainty than I know even that the Earth revolves around the sun, which I'm pretty damn sure about. With respect to the piano and the black hole, I want to say that the existence of these things and the ontological truths associated with them are entirely independent of our sense experiences. This is the mark of ontological truth, after all: it's true irrespective of what we think about it, or even whether we think about it, or whether we can think about it. So yes, ontological truths cannot be directly linked to our senses. Using our senses to gain knowledge is a primitive way of doing science. And science, as we've seen, doesn't establish ontological truth, just knowledge.

@WalterP you've raised some excellent questions, which relate directly to the next topic I was hoping to explore. We definitely need to look at how science relates to all of this. Please bear with me. I'll get back to you over the next couple of days.

At this point we have a sketch of a theory of truth. There are lots of questions that remain to be addressed, and lots of special cases that need to be treated, but hope the idea at least is clear. Truth is a property that statements that humans make may or may not have. Human statements are true if they express a propositional content that corresponds to an actual fact. The type of fact that the proposition in question refers to determines the nature of the truth in question (ontological or epistemic). There is much more to be said about truth, and I’ll come back to it. But first I want to spend some time considering belief and knowledge. I think the notion of belief is much more intuitive than the notion of truth, so long as we have a notion of truth firmly in mind already. A person believes a proposition if they think that it is true. That’s pretty much all there is to it. Notice, though, that if this definition of belief is to work, we do need to understand what it means for a proposition to be true. This is why I started this thread by looking at truth, and am only now moving on to belief. Not taking this approach leads to all kinds of problems, such as, for example, people saying things like “it’s my personal truth, because I believe it”. In general, this kind of statement is nonsense, but one does hear these kinds of things expressed from time to time. Notice as well that it is perfectly possible, on this definition, to believe things which are false. It just means that we think something is true incorrectly. I might believe that the earth is flat. I’d just be wrong. A question that has been raised previously on these forums is whether or not we are able to choose our beliefs. I think the answer to this is “yes” in some cases and “no” in others. Suppose you tell me that you can deadlift lift 600 pounds. I’m relatively unlikely to believe this on its face, because it seems pretty unlikely. Nevertheless, if I know you quite well, and have good reason to trust you, and you offer me your most sincere assurances, I might say “you know what, I’m going to choose to believe you”. Or I might choose to remain skeptical. Either way, I do have some choice in the matter. Now of course, if you tell me that you can deadlift 3000 pounds, I’m going to have a much harder time believing you. The point is this: if the claim being made is reasonable, we have a fair amount of leeway in choosing to believe it or not. If the claim is fantastical, we tend to lose this leeway. Another example: if I get home from work and my wife tells me she walked around the block, I’m probably going to believe her. I could choose to be skeptical, and indeed, she could be lying, but it seems probable that I’d just take her word, and choose to believe her. On the other hand, if she said that flew around the block under her own power, I’d have a pretty hard time choosing to believe her. The degree of choice we have in our beliefs seems to be in direct proportion to the reasonableness of the claim. Now let’s turn to knowledge. I’ve written before on these boards that I think knowledge reduces to firmly held belief. I differ in this view from the traditional justified true belief account of knowledge. Part of the reason for my difference has to do with the Gettier problems, but also I think it is fundamentally incorrect to require that knowledge be true. I think there are many cases where our level of certainty in some beliefs leads us to claim knowledge, and later we discover that we were incorrect. This happens all the time in science, which is an idea that I’ll explore more in a future post. One of the key distinctions between belief and knowledge, in my view, is the degree of choice we have. As I said before, where claims seem reasonable, we may have a fair amount of leeway in choosing our beliefs in some cases. This is particularly true in cases where no actual substantive justification is being offered. Again, if my wife says “I walked around the block”, I may choose to believe her or not. But if she says “I flew around the block under my own power” I don’t just fail to believe her; I know that she did not do this. The claim is absurd, and I have very good reasons to think that it isn’t possible for her to fly under her own power. Consider, though, that there was a time in history when airplanes were inconceivable. At this time, on my definition, it would have been correct for people to claim knowledge that human flight is impossible, full stop. Clearly such a claim is not true, though. This is an example of why I think that it isn’t necessary that knowledge be true. So belief, on my account, is thinking that something is true, and knowledge is really really thinking that it’s true, usually with significant reasons for doing so. We can choose our beliefs, at least in some cases, but we can’t choose our knowledge. This is not to say that we can’t choose to learn new things. Obviously there are many things I don’t know, and some of them I don’t know because I’ve chosen not to learn them. Moreover, many of the things that I do know, I know because I have chosen to learn them. So in this sense, we can choose our knowledge, but I think it is fairly clear that this is a different kind of choice than the type that I’ve been referring to up until now. An interesting thing to note at this point is that on the account that I’ve given so far, belief and knowledge have the capacity to create truth. When I was discussing epistemic truths earlier, I made mention of the fact that Justin Trudeau is Prime Minister of Canada. And the fact that he is Prime Minister arises from people’s belief that he is Prime Minister. So people’s belief that he is Prime Minister literally makes it true that he is Prime Minister. This is an incredible result. It seems, on the account given so far, that human beliefs are not just about what is true, they can actually determine what is true. Now, of course, that Justin Trudeau is Prime Minister is an epistemic truth, not an ontological truth. So maybe it is the case that human beliefs can create epistemic truth, but surely it’s not the case that they can create ontological truth! That would be really strange. Well, consider the statement “George Washington was President of the United States in 1792”. At the time, that he was President was an epistemic truth. It was true because people thought it was true. But now, in 2019, that he was President in 1792 is a matter of historical fact. It’s true irrespective of what anyone thinks about it. If everyone died tomorrow, it would still be true. This is the mark of an ontological truth. So now we really have an interesting result. It seems, on this account, that human beliefs have the capacity to create not just epistemic truth, but ontological truth as well. This may well seem absurd to some people, so I’m going to stop there for now and see if anyone objects or raises questions.

@Karna, thanks for this. I think I understand what you are saying a bit better now. Please read my next post on how I view knowledge and belief, and let me know if we have a substantive disagreement. I don't think we are that far apart, really. We can come back to the examples you raise here, or the to ones I give there at that point.

Hi @Karna, and thanks for joining the thread I want to make sure I understand what you're saying here. It seems that you are saying that knowledge underlies belief, and that both underlie truth. That is, in order to believe something we must first know it, and in order to get at the truth, we must believe something. Is that a correct reading of what you've said? I would want to put this the other way around. Being taught about gravity without experiencing it, in my view, would lead to a belief about how gravity works. I think knowledge is a type of belief, but that it is stronger than mere belief. More on this is another post, but for now, let me just give brief example: I believe I will be at work for most of the day today. I wouldn't say that I know I'll be at work. I could have an accident on the way to work. This is just to illustrate why I think that belief preceeds, and is weaker than, knowledge. I've bolded your use of the word know here, because it illistrates what I was saying above. Knowledge is stronger that belief. This seems to be a reversal of what you said earlier. I'm confused by what you mean here. Can you elaborate? I agree that repeatability is important, and I'll be talking about repeatability a fair amount when we get to science. An issue I'm having in gereal with what you wrote is that it relies on their being truth, and doesn't attempt to define it. My view is that to believe something is just to think that it is true. This is not a meaningful statement unless we know what truth is. As I've already said, I think knowledge is stronger that mere belief, but I do think it is a type of belief. So on my description as well, the definitions of belief and knowledge depend on our having a clear notion of what "true" means. That's why I began by trying to establish what "true" means. Incidentally, I was planning on turning to belief and knowledge next, so your post is quite helpful. If you would, please have a look at what I've said about truth so far, and give me your thoughts or objections. Nothing is carved in stone, but I want to secure the foundation as much as possible before I really move into knowledge and belief.

I mentioned a side-question earlier that I want to return to for a moment. The question was, are all statements which are not ontologically true, ontologically false? My answer is no, and in this post I want to justify this answer. This will leave us able to take our next step, and begin to examine epistemic truth. Consider the sentence "the king of France is bald". This sentence has been analyzed ad nauseum by philosophers of language everywhere, but it's still a good starting place for the point I want to make. The problem with this sentence is that France does not have a king. So we want to say that the sentence is false. But if it is false, the by the law of excluded middle its negation should be true, which is to say that the sentence "the king of France is not bald" should be true. But this sentence has the same problem as the first. So what to make of this? Bertrand Russell wanted to say that the sentence is basically incomplete. He thought it asserts more than the words actually say. His treatment boils down to saying that the sentence should be "There exists exactly one king of France, and he is bald". This sentence is clearly false, because there does not exist a king of France. The problem with the law of excluded middle is, thus, avoided. Gottlob Frege's earlier view was that this sentence presupposes that the king of France exists. All that it actually asserts is that this individual is bald. Because the king of France doesn't exist, the sentence fails to refer to anything, and thus doesn't have any actual propositional content. So it's neither true or false. I'm inclined to agree with Frege here. The reason for this is that Russell wants to treat the sentence as if it should be a formal sentence. The problem is, it isn't a formal sentence. It's an ordinary language sentence, and it doesn't say "there exists exactly one king of France, and he is bald", it just says "the king of France is bald". Yes, Russell's sentence is false, but that's not the sentence we're talking about. We may come back to the difference between formal and ordinary sentences if we ever get to formal truth. For now, though, the point is that I think the sentence "the king of France is bald" fails to express any actual propositional content, so it can't be true or false, at least not ontologically. But this leads to the next problem. Is it even possible for this sentence to be ontologically true? Suppose Pierre is the king of France, and Pierre is bald. Is the sentence ontologically true in this imagined scenario? I want to say that it is. It corresponds to a brute fact in the natural world. "King of France" refers to Pierre, and "is bald" expresses the proposition that Pierre's hair is lacking in quantity. Fine. No problem there. But what about the related sentence "Pierre is the king of France?" Is that true? Well, obviously I want to say yes, because it's my example, and I asserted it to be true. So in my example, Pierre is actually the king of France. That's a fact. The statement "Pierre is the king of France" corresponds to this fact, and is therefore true. But hold on. That Pierre is the king of France is not a brute fact about the natural world. There might be a revolution, and Pierre might lose his throne. So now we have to ask "what is it that makes him the king of France?" Clearly in the above example, the thing that makes Pierre king is my declaring that he is king for the purposes of the example. Fine. How about an example that is grounded in the real world? Justin Trudeau is the Prime Minister of Canada. This is true. But I want to say that it isn't ontologically true. That he's Prime minister isn't a brute fact about the natural world. Nevertheless, it is a fact. But it doesn't have to be a fact. What is it that makes him Prime Minister? Well, leaving aside the particular legal details, the essence of the answer is that he's Prime Minister because the people of Canada think he is Prime Minister. If all Canadians decided tomorrow that he wasn't Prime Minister, then he wouldn't be. (Actually, in this case, it wouldn't even take all Canadians deciding, just a majority in the House of Commons, but that's beside the point). Nevertheless, it's true to say that he is Prime Minister, and the reason it is true is that people make it true by thinking and acting as if it is true. I call this kind of truth epistemic truth. Notice the clear difference between epistemic truth and ontological truth. That money is valuable is another epistemic truth. If everyone decided that it wasn't valuable, then it wouldn't be valuable. Nevertheless, it really is valuable. By contrast, that the Earth is round is an ontological truth. It doesn't matter at all what we think about it, the Earth is just round. Another thing I want to point out is that epistemic truths are quite often conditional on context. You can be married in one country, and not in another. Is it true, in this scenario, to say that you're married? That depends on the context. I've been blathering on here for a while now, so I'm going to pause again before moving on. A brief summary seems appropriate: We've seen that on a few basic axioms it follows that people can make statements about facts in the natural world. These statements are true if they adhere to the facts, and false if they violate the facts. We've also seen that humans have the capacity to create facts via thought and action. Statements which correspond to this second type of fact are being referred to here as epistemically true, while statements which correspond to brute natural facts are being referred to here as ontologically true. I think a great deal of confusion arises in ordinary conversation because people fail to make this distinction, and just refer to both types of statements as true. To my mind, they are very clearly different, and recognizing the difference is vital if we are going to move forward to form a robust theory of truth, knowledge, and belief.

I remember that thread. It's a good one. With respect to the opening post and the graphic, a few things come to mind. First, I think it's entirely possible to make an ontologically true statement which does not represent a complete picture of the ontological truth in question. This is illustrated very nicely by the graphic in BAA's OP. The question of the extent to which we can access and understand the actual nature of reality is one that is very important, and we'll get to it here if all goes well. There are a lot of questions about human knowledge and understanding, and by extension, about the nature, power, and limits of science that will need to be addressed. Some of these issues were touched on in that thread, and we may find it helpful to look back there as the conversation progresses.

Edgarcito, please refrain from posting in this thread unless you intend to stay on topic. I've been at pains so far to clearly explain what exactly I mean by truth. I've barely begun, and I've acknowledged that there are lot of issues that still need to be treated. I'm coming to questioms of knowledge, certainty, science, and so on, but we aren't there yet. So please don't try to derail this thread. Thanks.

So far there have been no substantive objections to the axioms proposed in OP, or to the axiomatic approach in general. If anyone wants to raise objections, please feel free to do so, but in the meantime I’d like to move on, and begin to explore ontological truths in more detail. Last time I concluded by saying that there is a kind of truth which corresponds to brute facts about the natural world, and I called these ontological truths. I want to be a bit more rigorous in my exposition of this kind of truth. To that end, I want to return to the axioms, and note that it follows from the axioms, under normal rules of inference, that humans exist and are capable of thought, communication, etcetera. If anyone wants to challenge this they may, but I’m going to take it for granted for now. Once we have human thought and communication, we are able to consider statements and claims that humans may make. I don’t want to go too deeply into the philosophy of language here (it’s a very big subject, and I want to stay focussed on the task at hand), but it seems to me to be fairly straightforward that many human statements/thoughts have a definite propositional content. Let’s refer to these generally as propositions. Many propositions concern states of affairs (or processes, constants, whatever) in the natural world. For example, I may say “The earth is round”. There is a definite propositional content to this statement, and it concerns a particular state of affairs in the natural world. We want to say that this statement is true, and indeed, I propose that it is true. But now we need to ask what, precisely, this means. We’ve already established axiomatically that the natural world exists, and that there are definite facts about it. I propose that the proposition “The earth is round” is true precisely because that the earth is round is a brute fact about the natural world. This is an example of an ontological truth. It doesn’t matter what you, I, or anyone else thinks about it. The earth is just round. For that matter, it doesn’t matter that I made the proposition that the earth is round. The earth would be round if everyone thought it was flat. Furthermore, it would be round if everyone was dead. This is one of the metrics by which we can tell whether a truth is ontological or not: ask yourself, “would it still be true if everyone died tomorrow?” If the answer is “yes”, then I want to say that we are discussing an ontological truth. Of course, we haven’t yet discussed other types of truth at all here, so perhaps I’m getting ahead of myself. I'll come back to this. The point, thus far, is this: if a proposition presents a claim which corresponds to a fact about the natural world, then that proposition may be said to be ontologically true. The proposition “the earth revolves around the sun” is true if and only if the earth actually revolves around the sun (it does). The proposition “water boils at 65 degrees Celsius” is true if and only if water boils at 65 degrees Celsius (it doesn’t). (As an aside, this result is referred to as disquotation, and it’s a usual feature of most theories of truth. Philosophers of language have a lot to say about this. See the redundancy theory of truth, if this is of interest.) So, as long as we are discussing ontological truths only, we are left with statements which correspond to facts in the natural world being labelled as “true”. An interesting question is, are all statements which are not ontologically true, ontologically false? My inclination is to say no, because some statements don’t have actual ontological propositional content. More on this in a future post. For now, though, I want to point out that statements are ontologically false if they claim something which violates a fact in the natural world. “The earth is flat” is ontologically false, because the earth isn’t flat, it’s round, and that's a brute fact. These ideas, as I mentioned earlier, align fairly well with the classical correspondence theory of truth. As should be clear by now, I think that the correspondence theory has a lot of merit, I just don’t think it’s the end of the story. I’ll stop there for now, and see if anyone has any questions or challenges. In future posts I will explore other types of truth, as well as questions about how we can know that ontological truths are actually true. For example, I’ve said that “The earth is round” is true if and only if the earth is actually round, and I’ve asserted that it is. We are perfectly entitled to ask “how do we know that the earth is round?” I recognize that this is a valid question, and I’m coming to it. But it’s a question about knowledge, not truth. All in due course.

You're right, I didn't say anything about the conditions for reason. The reason why I said that we don't need to take people who are being inconsistent seriously is that if contradiction is permitted (and contradictions arise from inconsistencies) then all statements turn out to be true. This is absurd.