PoppersTruth

Quora Answer : What is truth?

Aug 13, 2015

Well, I'm a Popperian "critical rationalist", so I basically follow his line.

I think that truth is not a binary value where something is either true or false. Instead it's a model which approximates "how things really are". One model can be "more true" than another.

We never have transcendental access to "absolute truth". Our model is never quite the same as reality. On the other hand it IS meaningful to talk about there being a reality. And it is meaningful to talk about one model being closer to it than another.

(Popper uses Tarski to make sense of this. He suggests that we imagine that there was a language which could accurately describe reality. And then a metalanguage which would be used to translate or describe the difference between your model and the reality. Model A is "closer to the truth" than model B when the description of the difference between A and the reality is shorter than the description of the difference between B and the reality.)

Of course, no one is suggesting that we have, or could have, access to this metalanguage. But the fact we can consider it makes it meaningful to talk about relative differences, and therefore meaningful to talk about truth itself.

So, an example : Einstein's relativity is "more true" than Newton's model. But Newton is "more true" than, say Aristotle. Newton isn't "just false". This sense of "more true"ness could hold up even if we discover that Einstein is overturned tomorrow in favour of the Smith Model which makes even better predictions than Relativity.

Of course, this model of truth isn't the same as the one used in our logic textbooks. My personal feeling here, which I haven't thought too hard about, is that true and false in logic are merely convenient abstract symbols, much like numbers. The entire system of logic turns out to have useful predictive / modelling powers, just as the system of numbers does. But logical true and false ARE just convenient symbols. Whereas the Popper / Tarski notion of truth as "approximate accuracy" has greater metaphysical "reality" in some very crude and handwavey sense.

Quora Answer : What do you believe is right?

Jul 25, 2014

When I answered, this question was another more like "what is ''truth''?"

I like Popper's use of Tarski here.

There's a way the world really is. And there's our model of it.

And you can imagine that, in principle, (obviously we'll never have it in practice) there could be a "meta-language" that allowed us to describe the differences between our model and the reality.

So now imagine we could measure the length[1] of that description of the difference. The shorter that description needs to be, the more "right" we are.

The nice thing about this definition is that the metalanguage itself can include all sorts of abstract / complex concepts, which means that the ultimate length (ie. quantity of "wrongness" we have) is not necessarily a simplistic measure (eg. how many incorrect statements are there.)

This gets around the problem of, say, the stopped clock. Simplistic attempts to measure the gap between our model and the reality, that simply count numbers of errors etc., would end up saying that the stopped clock (which is right twice a day) is MORE "right" than the clock which is five minutes fast (and so never, actually correct). But a measure which includes the full expressive power of language (to make generalizations or describe more abstract relationships) can express the difference between the fast clock more concisely than the stopped clock.