Sure mathematical expressions are expressions of a language, but the name of constants and how we describe them, isn't what matters.

It's the fact that a shape that has perfect symmetry in infinite directions, the effects of same weather phenomena we called lightning and the limit on information propagation (and million other things I just forgot about) all have a thing in common.

And all this is totally unrelated from our perception or even the existence of humans.

> just linguistic notations stacked upon each other until statements like 2*pi*r = c are true.

You can totally make sound linguistic notations, that just have no grounding in reality. It seams like you think it's only about the linguistic statement, but the language is invented to describe something that exists outside of it.

> pirate was honorable

The pirate's victim begs to differ and any pirate thinking about them agrees that they do. People choosing to act against what they know is moral and still wanting to be called moral (especially in their self-view), is very different from them thinking the behaviour itself is moral from first principles.

Buying T-shirts/other clothing not made in the first world (which is nearly every one) is, I think, totally socially accepted, I wouldn't judge anybody on that (because there is no real choice) and I'm also doing it myself without thinking I'm doing something wrong, yet I think it is immoral to support, what I would call, slave-labor and having an economy building on that. Most people creating that system probably acted rationally and sound, but failed to be moral in a fundamental way, because they think money is everything. Yet I wouldn't judge them for that, because that is just so human (and also because I think that's for me to do, but that's religion).

My country is supporting the Ukraine. I think moral politicians need to care for their country and need to act for the protection of their people. It is also good to help people in need, even if you need to defend them. It can be also the better decision to kill the dictator, then to not do that. I absolutely support politicians sending weapons to Ukraine and think I would also see myself forced into deciding that way if I were in that position. But I would hate myself for it and would see myself as committing large unforgivable (for me) sins. Because killing people is ALWAYS immoral. The correct choice would always be to surrender, but I don't think I would do that.

The nazis (the real ones from Germany in world war 2) absolutely thought that killing humans is horrible and completely immoral. They didn't try to change this perception at all. What they instead did, was declaring that Jews aren't humans. And that it is good to kill them, because they are a larger threat to the real better humans. The soldiers and special forces didn't disagreed that what they do was horrible. They think they were heros FOR doing the immoral thing, because it was necessary. They coerced each other into doing it, because not doing it was cowardly as it meant claiming to be able to stay moral while letting all the others own doing bad stuff.

As you may have already imaged I think moral relativism is wrong. What is good or bad is independent of what people do or think it is. I also think law positivism is not what morale is about.