Magic as a social tool.

[Mark]

It seems like you guys are on the exact same page.
And 'invaluable' indeed means priceless/worth a lot.

However, I would personally (even though magic is always an art, as that is just what it is) never call it an art if it isn't used for the purpose of being that, or if not enough effort and practice is put into it. I think the same about every art form as for that.