joralex writes:
We "understand" NOTHING.
I don't think I know what you mean by "understand". There may well be philosophical viewpoints that would make you correct. However, as an analogy, would one say I 'understand' another person if I can say what they will do or say under given circumstances. Colloquially, I think we would agree that that is a reasonable level of understanding.
We have a number of areas where we can predict very, very precisely what nature will do under given circumstances. I would consider that to be a form of understanding.
What would you consider "understanding"?