Nationalities are a social construct, a bit of a shared delusion we all believe in. If we all stopped believing in them at the same time, they would cease to exist. That’s how they can not be “true”. Whether or not it’s useful or relevant to think that way depends on the situation. And that doesn’t mean they don’t have real consequences.
As for philosophies, he’s referring to living your life by any particular philosophy, whether or not it’s “objectively” the best way to live.
As for philosophies, he’s referring to living your life by any particular philosophy, whether or not it’s “objectively” the best way to live.