It's said that actions speak louder than words.
We judge people by how they act, not what they say. This applies equally to institutions and governments. We don't always listen to politicians - we look to the actions of the governments they represent. Sometimes, it's the words left unsaid that give the greatest insight.
These are simple truths, but they have a deep resonance for the Scottish independence debate in two particular areas: the proposed sterling zone, and Scotland's position in the European Union.
On a sterling zone, there are many words to consider, quite a few silences, and a number of actions. Chancellor George Osborne says a currency union is "unlikely".
Only this week, a Treasury spokesman said that such a union was "highly unlikely to be agreed as it is highly unlikely to be in the interests of either Scotland or the UK". A number of variations on the "uncertainty" theme, then, but what these Unionist politicians have not said, and will not say, is that the remainder of the UK won't enter into a currency union with Scotland.
They refuse to rule it out because a currency union is overwhelmingly in the interests of both an independent Scotland and the rest of the UK (rUK). They know that hundreds of thousands of jobs in England, Wales and Northern Ireland depend on exports to Scotland, and they can't endanger those by refusing a sterling deal.
If we look at the actions around currency, in the Scottish Government's scheduled talks with the Bank of England and the Treasury's undertaking on the UK debt pile, we see the ground work of a currency union being laid.
The pattern is the same in relation to the question of Scotland's EU membership. We hear various individual European politicians suggesting that, if there is a Yes vote, Scotland will have to apply for EU membership as a new state.
But we don't hear anyone suggest that Scotland's membership of the EU might be vetoed. If we look at how Europe actually operates and examine Europe's actions, we see an organisation that is expansionist; willing to bend the rules to achieve that aim (look at East Germany); puts obstacles in the way of a member state leaving; and will jump through hoops to prevent a fracturing of the eurozone.
Seen in the light of these actions, the loss of Scotland's territory would be anathema; the loss of Scotland's territorial waters would be unthinkable; and the loss of five million citizens would run against EU founding principles.
Of course, the UK Government could put the question of the sterling zone and Scotland's EU membership beyond doubt by setting out a definitive position on a few simple questions.
l Is the UK Government categorically ruling out a sterling zone? Yes or no?
l Is the UK Government in favour of Scotland becoming an EU member immediately upon becoming independent?
l Would the UK Government support a Schengen opt out for Scotland?
The UK Government won't do this because it's trying to preserve its negotiating position in the event of a Yes vote and because a refusal to set out a clear position produces "uncertainty", which is the No campaign's chief tactic.
If the referendum is to "deliver a fair test and a decisive expression of the views of people in Scotland and a result that everyone will respect" (as in Electoral Commission advice), Westminster needs to set out its position.
It needs to engage with the Scottish Government, the EU and other international bodies to provide clarity if Scotland votes Yes.
It is clear that neither the UK nor the EU will act against their own interests. Judged on the actions of the UK Government and the EU, it is reasonable to expect that there will be a sterling zone and that an independent Scotland will enjoy a smooth transition to full EU membership on terms similar to those enjoyed by the UK.