A key critical-thinking question is:how on earth would you know? How could anyone,no matter how expert,look 45 or 55 years into the future and count the number of jobs and careers young people will end up having,even on average?

We can’t forecast with any confidence what the next five years will hold,let alone the next 55. Any genuine expert would hedge any guess they made with a dozen caveats and qualifications. Anyone who can be as certain as 17 and five is more entertainer than expert.

Do you remember when Julia Gillard dispatched Kevin Rudd in 2010? She had a to-do list of problems inherited from Rudd – including his mining tax and emissions trading scheme - that needed to be dispatched forthwith in readiness for an election.

Malcolm Turnbull’s successor seems to have a similar to-do list. Actually,the plan to raise the age pension age to 70 is inherited from Tony Abbott. It’s one of the few cost-saving measures remaining from the many included,but since abandoned,in Abbott’s first budget in 2014 – a budget so politically disastrous it has blighted the Coalition government throughout its life.

The higher pension age proposal was implacably opposed by Labor and Senate crossbenchers alike. It was already a dead letter and it’s no surprise Morrison has dumped it.

You can believe that,should Morrison be elected,he’ll stick to his promise. But the eligibility age wasn’t to reach 70 until July 2035,and a lot could change between now and then. Say,17 prime ministers and five changes of ruling party.

We’ve been raising the pension age since the early 1990s and we still are. This has raised little controversy. So it’s not hard to believe that,by the time today’s school students are approaching 70,the age pension age will have drifted up from 67 to 70.

In 1993,the Keating government decided to increase the pension age for women from 60 to 65,phased in over 20 years.

In 2009,the Rudd government decided to phase up the pension age for men and women from 65 to 67,starting six years later. At present we’re up to 65 and six months,and it will rise by six months every two years until it reaches 67 in 2023.

Abbott’s plan was to wait a further two years then,from July 2025,raise the age by six months every two years until it reached 70 by 2035.

A point to ponder is that it was Labor governments that are getting us up to 67,even though Labor has so righteously opposed adding a further three years. Maybe it’s OK if they do it.

There’s no age at which people must retire. The rationale for raising the age at which we become eligible for retirement assistance from the taxpayer is we’re living ever longer,healthier lives.

That’s a good thing. But it comes at a cost to the community – particularly to younger taxpayers – if we insist that those extra years of healthy life must be spent in longer years of retirement rather than work,thus raising the proportion of non-workers to workers.

As I’ve notedrecently,one way we’ve used to slow the ageing of our population is high levels of younger immigrants – but this too carries costs many people don’t want to pay.

The notion that retirement beats working is the great delusion of middle age. If the ever-diminishing minority of workers doing hard physical labour fear their bodies won’t last the extra few years,that’s partly why we have the disability support pension. We should stop stigmatising it.

If it’s too hard for older workers to find jobs,that’s an attitudinal problem among employers we should be – and are – reducing.

If workers find their jobs so unpleasant they can’t wait to retire,that’s a communitywide problem of misguided employers we should be correcting directly,to the benefit of all wage slaves.

Ross Gittins is theHerald’s economics editor.