Interesting dissertation on the types of truth, but ultimately non-responsive to the OP. The question was what is truth, not what are the types of truth. Should I ask what pasta is, I wouldn't be requesting an itemization of the types with an explanation of the distinctions between penne and linguine, but I'd like to hear about flour and water.

And that's the truth.

well across these thinkers, a better distinction is tautological, EMPRICAL, and causal. And yes, they all do not believe propositional logic by itself can cross a semantic turnstile, so causal truth requires epistemological additions beyond those in syntactic languages.

I think that we are at cross purposes.

The OP asked for a definition of truth. You provided three ways in which one might justify claiming that a statement was true. I'm pointing out that this doesn't answer the question.

What's wrong with ostensive definition?

It is the formal definition of philosophical truth in modern metaphysics. There is no 'justification' involved.

That is to say, if you ask a professor with a PhD in modern philosophy, who has read several thousand books with different opinions on the subject, that is as good an approximation to a short answer they the professor would state that I can currently write.

There's not, but were you able to decipher the meaning of truth by the presentation of the sub categories of truth? I wasn't. At best, I was provided an encyclopedic statement of truth subtypes where I could then begin drawing my own conclusions as to what they had in common that made them all truth.

At any rate, your interpretation of his post as ostensive is generous. I took his post as a statement that there were 3 seperate truths, without a necessary overlap that distinguished them all as truth. That interpretation wasn't suggested in his post anywhere.

Nothing is wrong with an ostensive definition. If you are not interested in modern philosophical theory, talk about whatever you like. But I did revise the definition in response to constructive comments, and as people frequently use wor4s like 'right and wrong' interchangeably with 'true and false,' and the issue of truth and 'wrongness' in is in the last paragraph.
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In modern philosophy, truth is defined by formal logic on propositions (statements). There are three basic kinds of truth evaluation, which I here attempt to express in way compatible with the thinking of the modern philosophers Russell, Whitehead, Moore, Wittgenstein, Carnap, Strawson, Putnam, Searle, Kripke, Popper, Kuhn, and Davidson. According to all these various thinkers, truth is the result of evaluating a proposition, but the relation between truth and the proposition itself can be different depending on epistemological considerations.

• Tautological truths within formal systems, such as mathematical equations. These are established by syntactic consistency with core axioms. The core axioms themselves describe the formal systems, and so truths at this level are necessarily true, in accordance with syntactic rules which are themselves defined in formally as logical propositions. These propositional systems can also define rules of deduction and inference without introducing meaningfulness and causality.
• Empirical truths, which are determined via ratification by observation of material objects, states and events, as long as the propositions describing material states and events are logically coherent. If the observation verifies the proposition, then the RESULT of the observation is factually true, but the proposition itself without empirical ratification remains a proposition that is neither true nor false, and is simply an assertion. The specific and exact nature of truth itself depends not on facts or data, but on the epistemological factors relating the proposition to the material world in different metaphysical systems, most predominantly in the theories that define the relation of subject and predicate to objects, states, and events in the physical world. These theories add semantics (the meanings of words) to the syntactic relationships described in first-order logic. 'Internal' states, resulting from consciousness, are also evaluated empirically. The nature of consciousness itself is part of the epistemology.
• Causal truths, which again first must be generally consistent within the rules of propositional calculus, and additionally, they must not contain any syntactic fallacies of deduction or inference. These are the most complicated forms of truth, and the basis of science. They are the most complicated because causal relationships cannot ever be proven necessarily true. They can only be proven not to be false. That distinction remains one of the least understood aspects of truth in the current world, because causality is so often claimed, yet errors in statements of causal truth are so frequent. The metaphysical factors of causality are more frequently better understood if they are known to exist, but only a small number of people even know that there are metaphysical factors involved. Those who do know the metaphysical factors understand that the relation of the subject and predicate's in the cause, to the subject and predicate of the result, is an abstraction that can be very complex.

While these are the *basic* forms of truth, the truth of many statements rely on combining two or more these forms together. For example, most commonly believe they know that the sun will rise tomorrow. This is based on empirical observations of many prior days where the sun did rise, leading to the simple second-order deduction that it will rise again tomorrow. Logically, one cannot know whether the belief is true that the sun will rise tomorrow until after the event has occurred. But in most cases, when sufficient empirical validation of many prior similar events has occurred, it is loosely assumed true that the same future event will occur again in the same circumstance. This 'axiom of probabilistic certainty'  is the foundation of prediction in much scientific theory. The extrapolation of this axiom is the creation of the scientific method, which is designed to define the minimum number of observations necessary to corroborate a theory. As per the rules for causal truth, theories can only be corroborated and not be proven true; but modern science theory might still call a theory true based on the axiom of probabilistic certainty.

Beyond that, there are some other very specific forms of truth in philosophy. For example, there are 'self-generating' truths in linguistics, such as promises, statements of intent, contracts, and some statements of belief, which all become existent by their own statement. One should be aware these kinds of truth have limitations. For example, after making promises, it becomes true that promises were made, but the truth of the promise itself remains an indirect proposition, and still must be determined within the rules for the three basic forms of truth described above.

Truth in theology, morality, ethics, law, and metaphysics

Much confusion about truth has arisen in these fields, but by the above schema, the nature of truth itself is relatively simple. Theological systems make assertions about that which cannot ultimately be proven; morality strives to define that which is good or bad for an individual; ethics defines that which is good or bad for a society; law strives to define that which is right or wrong; and metaphysics strives to define that which is real. In all these cases the absolute truth of the assertions they make is undefinable. However within each of these disciplines, it is possible to evaluate the propositional consistency of statements within formal systems that they define; and from that, to evaluate the truth of their propositions empirically, within the formal systems themselves. so again, when different propositions within, or across, these disciplines contradict each other, it is not possible to evaluate which are true or false in absolute terms. It is only possible to demonstrate whether the claims by each system are coherent.

your interpretation of his post as ostensive is generous. — Hanover

I'm a generous fellow. I hope Ernestm was not claiming that there are tree sorts of truth. Looks like he is.

I'm going to go with redundancy.

I said there are three BASIC forms of truth evaluation across the thinkers Russell, Whitehead, Moore, Wittgenstein, Carnap, Strawson, Putnam, Searle, Kripke, Popper, Kuhn, and Davidson.

He wasn't ridiculing you for suggesting there were exactly 3 forms of truth, but for suggesting there was more than one truth.

I'm a generous fellow. — Banno

True.

My apologies for appearing to be ridiculing you. I'm of the opinion that truth is redundant; not an uncommon view. So my reaction to your presentation of a definition is that it's not a definition of truth, but of justification.

Tautologies do not need justification. Empirical statements are justified by observation.

Truth is the same in both.

Well, there are other perspectives on truth by other people. But they would not agree that their definition, is 'redundant,' because, for example, it is the basis of the philosophy of science, and the merit of a metaphysical system, in the modern view, is that it is no longer a case of how 'true' it might be, but rather how useful it is in improving understanding of the world. As science has greatly improved understanding of the material world, and somewhat helped in other aspects of reality, they believe their system of truth evaluation is of great merit. That's basically what they would say of it.

I don't see that redundancy undermines science. Indeed, it says nothing about science. 'F=ma' and 'It is true that: F=ma' say exactly the same thing.

What I am having a go at is the notion that the truth of a tautology might be a different truth to that of an empirical statement. If it was your intention to show that they are different, then I think you have not succeed.

Well it seems then, what I refer to as 'tautological truth,' as different from other forms of truth, is something with which we are in a agreement, but you simply think that it is 'wrong' to call 'tautological truth' a form of truth at all?

Tautologies are not true in a way that is different to other sorts of statements. That is, the "It is true that:" in "It is true that:A implies A" and in "It is true that: this sentence is in English" and in "It is true that: F=ma" mean exactly the same thing.

But the account you gave suggests otherwise.

the thinking is, if you state that a is logically equivalent to b, then the statement is considered true. However, the 'truth' which one considers is a semantic evaluation, not a property of the syntactic system itself, and so 'truth' is not redundant, but somehow associated with the statement. Different epistemologists consider the relation in different ways, and the exact statement of each of their beliefs here could only be superficial. But in summary, there are 'naturalists; who hold that truth is an instrinsic property of the abstractions that create it. There are association theories, which hold that truth is one of the properties of a proposition. Kuhn believes that we attach truth by an act of wilful 'dubbing.' And there is Davidson, whose description is far too complex for me to even begin trying to state it in one phrase.

Now you may believe such distinctions rather arbitrary, so I will make one statement about why different views exist. It depends whether you think truth of a proposition exists before a person evaluates its truth value. That immediately starts to get into issues of monism versus dualism, or even in Wittgenstein's theory of logical positivism, whether language is the only thing that is actually real. So that is a deeper explanation of why the specific nature of truth is dependent on metaphysics, and it remains a hotly debated issue in modern philosophy.

Your answer does not appear to me to address the issue I raised.

It would be interesting to hear from Mew again.

My answer to the OP is that Mew, as a competent speaker of English, already knows what truth is, and that this would be demonstrated by their use of the word. Further, any proposed definition of truth would face the circularity Mew describes, but that circularity is not vicious if the definition of truth can be consistently ascribed to itself.

I'm very sorry, but the rate at which you are posting broke the page in my browser. I edited the statement in my last post to answer you properly.

Now I am remembering, it was a very long time ago, and I did hear the question asked why a truth value should be related to a syntactic proposition at all, and so why there should be any debate on the epistemology at all. The answer is that the purpose of modern logic is to make statements meaningful.

If you remove truth values from propositional logic, then you can create a simpler reductionist system in which statements about the truth of propositions are meaningless. But then the explanation of meaningfulness is also incomplete, and so such methods are of less merit.

This bit, then:

if you state that a is logically equivalent to b, then the statement is considered true. However, the 'truth' which one considers is a semantic evaluation, not a property of the syntactic system itself, and so 'truth' is not redundant, but somehow associated with the statement. — ernestm

Hmm. That 'A implies A' is true just on the syntax, surely?

This bit, next:

And there is Davidson, whose description is far too complex for me to even begin trying to state it in one phrase. — ernestm

Davidson takes truth as undefined, and uses it to elucidate meaning.

And I rather think that is a good approach. Truth is much easier to deal with than meaning.

Well that is the naturalistic view, which is that truth exists inherently as an intrinsic part of the proposition. if you believe that, then a proposition has a truth value regardless whether anyone thinks of it, and you end up having to postulate the existence of 'a priori' truth in the Kantian sense, and some people object to that.

So are you claiming that 'A implies A' might be false for some model?

Surely not.

I don't understand the relevance of that. Davidson does say that truth is undefined, but only because he is an anomalous absolute monist, and therefore, in his view, it is not possible to know, absolutely, whether truth exists a priori or not. But then he goes on to say some very complicated things about meaning as the consequence of which, truth can be known, but from an absolute perspectiive, only in an indefinite manner.

What does his theory of mind have to do with this topic?

are you claiming that 'A implies A' might be false for some model? — Banno

That is, are you claiming that one needs a semantic interpretation in order to identify basic tautologies? Because that seems to me obviously false.

the thinking is, if you state that a is logically equivalent to b, then the statement is considered true. However, the 'truth' which one considers is a semantic evaluation, not a property of the syntactic system itself, and so 'truth' is not redundant, but somehow associated with the statement.

if you state that a is logically equivalent to b, then the statement is considered true. — ernestm

Why?

That's like saying:

If you state that '"it is raining" is logically equivalent to "It is Thursday"' then the statements is considered true.

SO at present I'm not at all sure what you mean.

Those assertions are not an example of logical equivalence, as per my first and second basic definitions. That is an example of two empirical statements, because they require testing against the material world in order to determine their truth. An example of logical equivalence would be "10 in base two is equivalent to 2 in base 10.".