I've taken this sentence by Wikipedia but I see it in a weird way.
"Culture sophistic through criticism of the notion of truth arrives at a more radical form of relativism. Not only there is no truth absolutely valid, but the only measure becomes the individual: for each individual it's true only his own subjective perception. Similarly, this relativistic view of the world is applied to the field of ethics ... There are no good or bad actions in itself; each action must be evaluated case by case."
I see two possible interpretations:
There is not only 1 truth, but one for each point of view. For example on topic like death penalty there could be 49 reason pro and 50 against and going deeper and deeper we would simply see that the reality is a lot complex. And that "tags" don't fit it well. A math example could clarify the point. People see "truth" like a score calculated on a strong simplified model of the reality. But the model is too much simplified. It's not like a function from R^2 to R^3. But like a vectorial differential function from R^20000 to R^3000.
"since we can join logical sentences which contradict one sentence defined as truth, it means that there is no absolute truth". "Since we can wonder on the definition of any word and argue pro or against it this means there isn't an absolute truth.
I strongly disagree on the second interpretation since a reasoning is just a logical mental association based on our human limited simplified model, not the reality.
Imagine someone is arguing that the pain is not existing. Take him in a torture chamber with a button, that if is pressed, states that pain exists. Every argumentation in the world will not change the fact that he will press the button in a short time.
The question is: how do we get the philosophical speaking to stay connected with reality?
A mental model, a rational consequence of ideas can describe many realities, philosophy has a name for define philosophy which are bound to this real world and the common perception of it shared by peoples?
*who doesn't understand the question will go to the torture chamber :p (jokes aside, is my first question, and I know it's harsh to ask a philosopher to stay pragmatical, can you help me to clarify it?)