It seems the first time PR was used was in 1855. Canada and the USA are late (it seems that most of the places I’d be okay with living use proportional representation), but catching up sooner would be better than catching up later!

I’ll draw a parallel to another revolution: supposedly only two wars were fought to end slavery, in the USA and Haiti (everywhere else seems to have banned slavery with just legislation and compensation, for example in Britain), and I’d rather keep the number of wars over proportional representation at 0 rather than risking having a higher number, so advocating emphatically is important regardless of circumstances.