The Scotts are voting today to separate or not from the English (and, I suppose, from the Welsh, tho I doubt that's the issue). I have no expertize in the matter, and no position, either. It's not my business. Yet as I've followed the story from afar, it has been rather clear that the vote isn't about rational arguments. If folks all based their decisions exclusively on calm rational considerations based on cold figures and data, I don't see how today's vote could ever even have been mooted, much less enacted. If the Scots decide to go their own way they'll have to surmount countless obstacles, from the identity of their currency to their unclear membership in the EU along with 30,000 matters. If never the less they decide to do so it will be for for what are ultimately emotional reasons.
This is important. Much of the political discussion about how the world works assumes that people are ultimately rational or at least easy to understand: give them a good life and they'll behave nicely. The entire world of contemporary diplomacy is predicated on this: talking is better than killing, and there's almost always something to be talked about. Hence one engages with Iran, for example, and seeks leverage of soft power, and insists that implacable enemies must talk to each other until they've addressed the only real - i.e. rational - issues, and then agree on them and have peace. (Until the mid-20th century diplomacy wasn't like this, as the term gun-boat diplomacy tells. But that was then).
The interesting thing about the Scottish story, then, is that even in one of the oldest of democracies, in one of the wealthier countries in the world, a place with centuries of tradition of enlightened civilization, rationality will take you only so far. There comes a moment when other motivations for human action proves stronger. If that's so in the United Kingdom, it's even truer elsewhere.