can you have truth with a subjective language. I say it’s snowing, you say not, because we determine that “snowing” kicks in at different levels. Or perhaps we have different sensory inputs. If I’m facing the window and say the man has a red tshirt”, and you are facing away. Even if we agree on the definition of man, red and tshirt, you still don’t know if that’s true or not

Can you believe your own senses? A car air freshener tells your nose that theres freshly cut summer hay around, but there isn't. You watch a tv and see Sandra Bullock floating in space. That’s a lie, it was movie magic. Maybe you know that, maybe you don’t. You’re not even seeing her, you’re seeing some flashing lights which convert to electrical signals your brain interprets as being true. Can you trust those signals? People hallucinate all the time. The truth is they can hear voices, even though nobody else can, because of misfiring neurons.

You can probably have mathematical truth - at least as far as your universe appears to work. That truth can be tested and refined, but for day to day truth things are more nuanced.

> That can´t be it. By that statement if I belive that I can fly that would not be the "Truth".

1st what is to fly? You've already made assumptions i.e. beliefs elsewhere.

You can definitely fly. Try it on a cliff. You might die. You might not go very far. But you can.