I'm actually quite close to the OP:

"Truth" is - before anything else - a word, and the best way to understand what a word means is by looking at when a person uses it and to what ends he/she tends to use it.

In the case of "truth", we almost always use it when there is a perceived threat of de-legitimation from some challenger. We sense that this challenger will, or might accuse us of saying things that aren't true. Other times we might actively put our own good name on the line in order to reinforce an assertion by saying something like: "I don't just think it; I know it to be true." And so on.

"True" and "false", then, are the social practices by which we stabilize, social and internalize the meanings of our words and terms. They are the ways in which we go around (de)legitimizing each other's inferences and assertions.

As such, all linguistic communities necessarily have some standards for truth and falsehood... but this doesn't mean that they all have - or ought to have - identical standards.

But that's just my own opinion that may or may not be true. :)