THE First Minister often cites me in support of his case that an independent Scotland would become a member state of the EU.

Within limits, he is entitled to do so and I stand by what I have said. But it has reached the point where I have, in London, been called "the poster child of the Yes campaign". Yet I have always made it clear that I am a unionist and will vote No. Let me explain.

I have been involved in European affairs for more than 40 years. Throughout that time I have been guided by my belief in a Europe without borders where individuals are free to go where they want, to live where they like, and to trade and to work where they can. These are rights that we enjoy as individual European citizens and form part of our legal heritage. I cannot accept that a newly independent Scotland would automatically be excluded from the EU or that we could, at a stroke, be deprived of the rights we currently enjoy.

But that is as far as I can go. I have always said that there would have to be negotiations with the other countries of the EU. Much would depend on the outcome of negotiations between Edinburgh and London about the currency, the common travel area and a hundred and one other points of technical detail. The outcome of all these negotiations cannot be certain and there would be the added problem of Treaty amendment and ratification, though I think this has been exaggerated. While I believe that an acceptable outcome could be achieved, I do not believe that this would be possible by the Scottish Government's deadline for independence of 24 March 2016.

So I ask myself, What is the purpose of launching ourselves on this unpredictable sea of uncertainty?

For three centuries we have belonged to a Union that has allowed us, while maintaining our own institutions and traditions, to go where we want, to live where we like, and to trade and to work where we can. Scots have played a full part in framing the destiny of these islands (often for good though sometimes not).

According to the First Minister himself, "The bonds of family, friendship, history and culture between Scotland and the other parts of the British Isles are precious"(see his Preface to the White Paper, Scotland's Future). He assures us that destruction of the Union will have no effect on these precious bonds: "The social ties between Scotland and the rest of the UK will continue and thrive". Indeed, the White Paper is at pains to suggest that everything we value in the Union will remain the same.

But we cannot ignore the fact that, just as Scotland would be a separate state pursuing its own interests, so too would the remainder of the UK. Why should they treat us any better than we treat them? As a small but significant example, the Cabinet Secretary for Education insists that we will still be able (contrary to basic principles of EU law) to charge fees to their students which we do not charge to our own students or those from any other EU country. Yet he also insists that our Universities must retain their present access to UK research funds, because that would be "rational". People are not always rational and human relationships can be fragile.

I am disturbed rather than inspired by the claim that it is only through independence that we can regain our sense of identity and realize our potential. Rhetoric about identity has all too often been used to demean, or even to persecute, those who do not "belong" - witness our own sad history of religious strife going back to the Disruption of 1843 and beyond. I distrust appeals to identity, even if they are meant well.

I have never been in doubt as to my own identity. As far back as they can be traced, my ancestors came from the glens of Angus and the shores of Loch Tay. I was brought up in their tradition to believe that the way for Scots to realize their potential is through education and hard work.

Siren voices urge us to vote Yes or No on the basis of unprovable (and often improbable) predictions that we will personally be better off or worse off. It is said that the Union of 1707 was purchased by English gold. As Dr Johnson said: "That is no defence: it only makes you worse". Anyhow, I fear that, this time, the gold is at the end of the rainbow.