The concept of truth applies to a proposition and concerns the relation to its denotatum. In its simplest version, it means that a proposition is true if it corresponds to a state-of-affairs in the real world. This “correspondence theory of truth” was popularized by Alfred Tarski (1935) in his famous verdict: “The sentence snow is white is true iff snow is white.”

Most cases are less simple than this one and require a more pragmatically oriented concept of truth. The most important thing to note here is that for x to believe (that) p commits x to the truth of p. In other words, if somebody believes that p, then p is true for him. This leads directly to a constructivist view of truth, where no absolute truth exists. Truth is a relative concept: the truth of p is relative

1. to a a set of propositions with which it forms a theory and must therefore be compatible
2. to the source of evidence for p, which may be more or less trustworthy
3. to the sincere intentions of the person who says that p
4. and to a set of persons who believe that p.

These considerations apply to statements of logical, empirical and hermeneutic theories in different ways:

1. For a proposition of a logical theory, truth means that no contradiction arises from the conjunction of this proposition with the rest of the theory. Analogously, a logical theory is false iff it is inconsistent; otherwise it is true. Truth here is essentially based on #a.
2. For a proposition of an empirical theory, truth means (possibly in addition to the logical requirement #1) that it has not been falsified. If it has been falsified, it is false; otherwise it is treated as possibly true. That is to say, calling an empirical proposition or theory true is always under reserve; it only means that they have not yet been falsified. Truth here is essentially based on #b.
3. For a proposition of a hermeneutic theory, truth means truthfulness. A proposition is true if it is sincere, i.e. if it corresponds to the intentions of the human beings crucially involved be it in the communicative use of the proposition, be it in the state of affairs denoted by it. Truth here is essentially based on #c and #d.

Given the above, truth in logical and empirical disciplines becomes essentially a methodological issue. Methods guarantee the truth of their results to the extent they are objective, valid and reliable.