"Pluralitas non est ponenda sine neccesitate"
"...when you have two competing theories which make exactly the same predictions, the one that is simpler is the better."
- They are busy – not busy in the sense of subsistence but busy in the sense of economic activity
- They are places that attract immigrants – people want to move there
- They are quiet – in the sense that economic activity is limited
- They are places of emigration – people wish to move from them