In a year of big decisions, what does it mean to be Scottish?
Identity is one of the most evasive words in the dictionary - although the official documents of civic life such as the census, visas and passports try to define us there is always a lingering worry that they also confine us.
Identity is such a rich concept, why would we want to cheapen it with simple answers?
When I started out to make a documentary about what it means to be Scottish I knew what I didn't want it to be about.
I wanted to avoid the kitsch myths that are often trotted out - from "Brigadoon" to "Braveheart". Neither says anything about my life nor, do I suspect, does it say much about most Scots.
I am fascinated by how identity shifts and changes, how all of us offer up different versions of ourselves depending on where we are and who we are with.
I remember even in childhood that when my mum answered the phone, she put on a "phone voice" - it was slower, more polite and more English than her everyday voice. And ironically she already was English.
So clearly at that moment she wanted to convey a level of appropriateness and achievement to whoever was on the other end. She wanted us to sound like a good family - which of course we were.
One person who helped me to understand how evasive identity has become is the comedian, Bruce Fummey.
Like me, he's a St Johnstone fan who grew up in Perth. His Dad was Ghanian and his Mum Scottish and in the course of our conversation he told me being Scottish was very important to him, almost a form of belonging.
But he also explained that growing up as a mixed race child he felt he had to "prove" his Scottishness.
He told me: "I think growing up you kind of almost had to be more Scottish than the other Scottish kids."
Just to ensure his sense of self, Bruce is learning Gaelic - the indigenous, endangered and wondrous language of Scotland.
Identity is powerful and something people create for themselves, that has become even more complicated in a world where many of us take at least part of our identity from our passions - for me soul music and football but for others it might be surfing, skate-punk or science-fiction.
The documentary features those who are prepared to tattoo themselves with national symbols, people who surf in Scotland in mid-winter and strangest of all, Morris Dancers in Aberdeenshire.
The comedian Sanjeev Kohli explained that one of his big passions - the history of comedy - has a very strong sense of British identity. He grew up with Porridge and Only Fools and Horses and feels that has shaped him as much as his proud Scottish-Asian heritage.
He said: "Britain thankfully doesn't have an empire any more. But it does kind of have an empire in terms of punching above its weight in terms of exporting comedians and music to America. And that makes me immensely proud to be British. And I don't want to be divorced from that."
Although there are no plans under the terms of the Scottish government's White Paper on Scottish independence to ban Del Boy and Rodney, at the very heart of the "yes/no" debate are matters that are deeper and more heartfelt than fiscal autonomy.
It's clear that identity will play a role in how some people will vote in the forthcoming referendum.
Surveys tell us that the vast majority of Scots identify as Scottish "very strongly" but that does not directly convert into a simple pattern of voting.
Arguably it is this lingering and imprecise emotional attachment to popular notions of Britishness that may hold the narrowing balance of power.
Professor John Curtice of Strathclyde University told me that this imprecise sense of identity will play a pivotal role when voters go to the polls on 18 September.
He explained: "They are saying to themselves - look it isn't just about whether or not I feel Scottish and I want my country to become an independent state, it's also about - I also feel British, I feel some affinity with the rest of the UK and do I want to let that go.
"And I think probably that the yes side, to be able to win this referendum, actually one of their key tasks is to persuade people who have at least a modest sense of British identity, you can afford to let it go."
Making the programme has given me an insight into the great cultural diversity of Scotland and the many millions of ways we see ourselves.
It has reminded me that people will make their choices but it will only come after a dialogue within and what they really feel about Scotland's future.
- WatchFive Million Ways To Be Scottish, presented by broadcaster and journalist Stuart Cosgrove, on BBC iPlayer.