Businessman Mark Carnegie’s proposal for the wealthiest 15% of Australians to pay an additional 15% tax won’t be an immediate priority to emerge from this week’s tax forum, but it’s likely to be the one that’s still up for discussion in the years to come.

That’s because Carnegie brings a new vigour to the debate that follows his previous calls for an inheritance tax, given the wealthy venture capitalist is an unlikely advocate for taxing the rich. And he joins the likes of other wealthy and influential global players like US billionaire Warren Buffett in garnering headlines for their calls to “tax me more”.

Carnegie told the tax forum yesterday that Australia risked facing similar problems to those in Europe and the US if the wealthy don’t say “we will shoulder some of the societal responsibility”. He believes that by further taxing the richest 15% of Australians, the country can create a wealth fund for future generations and alleviate some of the challenges associated with an aging population.

Carnegie told The Power Index this morning that there were a number of significant supporters of his proposal in the room yesterday, especially those, he said, who “understand the demographic issue”.

Garry Weaven was one such supporter. A key architect of Australia’s superannuation system and The Power Index’s No. 6 Money Mover, Weaven said that suggestions that the tax rate be cut at the top end of town were “obscene”.

And entrepreneur Dick Smith was another key supporter, albeit a more predictable one given his vocal calls for the rich to give back. He told The Power Index this morning he’d written to Carnegie congratulating him on the move.

“I believe more wealthy people should say something about tax,” he said. “We’re simply not putting away enough money for pensions and superannuation.”

Cargnegie said he’ll wait to see the outcomes of the forum before determining how he plans to approach the debate in the future, noting that further taxing of the wealthy is likely to be an issue for as long as we’re still dealing with the challenges of an aging population.

“We need to have an open conversation about whether we want to fund this now during the boom or leave it for our grandkids to deal with later,” he said.

But assistant treasurer Bill Shorten has already dismissed the proposal, telling ABC Radio yesterday that “it’s nice of Mr Carnegie to volunteer to pay more tax” but that he believe the proposition is unlikely to go any further.

The Business Council of Australia, which represents CEOs from 100 of the largest companies in Australia, did not wish to comment on the proposal when called by The Power Index this morning.