I have this fantasy where former Scottish Secretary Michael Forsyth, now an ermine-clad provocateur in what Denis Healey once memorably described as the House of the Undead, is invited to address a cohort of 16 and 17-year-old Scots.

The ones he was anxious to exclude from any participation in the 2014 referendum.

First up will be a couple of servicemen and women, since their age has been no barrier to donning uniform and training for future front-line action. The list of casualties from Afghanistan boasts a dispiriting number of teenagers.

Let's throw in some married folks –eligible to tie the knot at 16. And some teenage mums and dads. Then trainees in anything from the emergency services to mechanical engineering and full-time students. How about young folks who had no choice but to become full-time carers for siblings or parents? And those who left school to go into full-time employment. Or, as HMRC calls them, taxpayers.

A diverse group of young Scots, but lumped together as if they were an indivisible, homogenous whole. What do they know about life, sniff the critics of voting age reform? How can they make informed judgments?

Sure there are 16 and 17-year-olds who have little or no engagement with politics or social policy. That's the same as any demographic from the ages of 18 to 80. Think back to the last time someone made an inane, ill-informed, remark about politics – chances are it was a middle-aged party conference bore.

It's true, younger voters are perhaps more likely to see the world in black and white with significantly fewer than 50 shades of grey. That's often because they've not yet had to swim in the murky waters of compromise and are infused with youthful idealism. I wouldn't mind more of that latter commodity informing our judgments as a nation.

Ageism, it turns out, is not a process confined to dismissing the contribution of older citizens, though they too suffer from the lazy assumption they uniformly share the same tastes and ambitions. The myth that Scotland's elderly are all knitting bedsocks while tuned into a boxed set of Larkrise to Candleford is partially dispelled by the inaugural Luminate creative ageing festival. The most attractive parts of its programme include Riskiryhmä, a 70-plus female rock band from Finland, and Dance Base's alternative take on the Olympics with We Are Golden! its over-60s dance class.

You can't make standard assumptions about any age group. Personally I won't be storming the doors of the Luminate tea dance: I still live in hope of someone offering me one-to-one drumming tuition. My close contemporaries seem to have spread their addictive tendencies promiscuously around golf, tennis, curling and painting.

Though it's certainly true that opportunities to enjoy later life are manifestly more achievable if you have the great good luck to stay healthy. And for that matter, if the NHS doesn't make treatment judgments based on crude chronology.

In theory it's illegal for hospitals to discriminate in this way. Access all Ages, a report published yesterday by the Royal College of Surgeons and Age UK, suggests surgery for men and women is being denied to fit older people because the age on their birth certificate appears to trump their fitness levels.

Older Scots also lose out disproportionately in the employment market. You can point to any amount of blue chip research that successful companies are those which achieve a healthy balance of youthful enthusiasm and time-served experience, but none of it seems to help men and women made redundant from early middle age onwards.

In a recessionary environment they've found themselves on the scrapheap at the moment they might have considered themselves in their employment prime. I have personal knowledge of one man in his 40s with a hugely impressive CV who took his own life following 250 failed job applications without reaching a single interview. A shocking proportion didn't give him the courtesy of a reply.

The moral is that it has never been more important to focus on people as people, rather than lump them into demographic boxes labelled too young or too old. One of the arguments advanced against lowering the voting age is that, statistically, younger voters are less likely to vote than the elderly. The counter argument seems to me more persuasive, especially in terms of a poll which will affect young futures to a greater extent than their grandparents, given the respective life expectancies.

It is the belief that if you engage with young Scots, respect their opinions and encourage their participation, the whole country will reap rewards.