“It is easier for a camel to go through the eye of a needle, than for
a rich man to enter into the kingdom of God." - Matthew 19:24
Because receiving wealth was regarded as a blessing or sign of God's favour, this has been understood as guidance for those who have wealth to use it before they die, and in terms of not being attached to wealth. Trade exchanges and the movement of currency provides mutual benefits, hoarding often causes problems and poverty. We also see such ancient guidance in the fifth pillar of Islam Zakat, which means paying a tax or tithe on savings. The book Debt: The First 5000 Years by anthropologist David Graeber goes into the dynamics of debt and hoarding over the long view. I find it interesting that we don’t seem to have the category of miser anymore, perhaps hoarding was more key in more uncertain times.
I would argue following Hume on Is/Ought, that we use moral reasoning from our values, but the values themselves are unreasoned. I would look mainly to game-theory as having shaped our intuitions there evolutionarily, eg about the social contract Is the tyrannicide perpetrated by William Tell morally legitimate? And I would look to Moral Foundations Theory about core values, as enabling systems of cooperation.
Setting a target for inflation, is about the process of balancing competing interests. I’d argue the UK making the economic levers to control inflation under the control of an independent central bank with a clear policy they are accountable to, was a moral improvement. Otherwise especially in election years, there was a danger of political decisions, eg that favour pensioners that vote at higher rates.
We begin our moral reasoning with intuitions about fairness and justice (moral foundations). We also prioritise our own interests and those of our groups, for various reasons, like depth of knowledge of what’s local, and Darwinian pressures. These need a process to balance, eg we need to avoid free-rider problems that destabilise systems, if we value the system.
Inflation is a high-level emergent property, that cannot be set directly, only impacted by policies that have a mix of consequences. The moral choices are about applying our values, balancing the interests of different groups for best net benefits. Power and leverage cause compromises to that, which social progress sees increasing mechanisms to manage. It comes down to practical experience that a low positive interest rate best secures this, like the UK target of 2%. It’s an interesting point that the UK housing market rise has seen many pensioners invest in property, and it shifts wealth through rising rents to the wealthy from those who can’t afford to buy a house - that kind of dynamic increasing without redress, increases inequity and risks of housing market failure, in terms of lack of availability or a crash. Action must be taken based on emergent consequences of economic choices.
A caveat is that countries undergoing a demographic transition from high to low birth rates, dramatically decrease infant mortality and poverty. So there is a moral duty to have higher inflation there, to incentivise greater investment. This tends to be the period of greatest economic growth for any country, and it's crucial to make big investments in infrastructure like transport networks and sewerage in this era, to secure long term wellbeing.