Message passing is general... it can apply to all the built-in types, and can also apply to all user-created types. It does increase brevity across a range of programs. You could even write all Arc code in that style, but I don't recommend that. I'm restricting my discussion of message passing to data types because message passing is clearly superior with regard to data types. I make no claims about the superiority of message passing with regard to things other than data types.

I've been using specific examples because as aw mentioned (http://arclanguage.org/item?id=14264) it's important to explain the problem that it solves, and also demonstrate how it solves the problem... but the concept is general.