Using the clean wage system to argue for parking charges in schools implies the years of free parking teachers have enjoyed amount to hidden perks, said Mr Seah Kian Peng (Marine Parade GRC) yesterday.

He added that the move has "tarred teachers with an 'unclean' wage", as he made the broader point that the Government should not look at all issues through a pure economic lens.

Calling for a rethink of the role of the market and of economic reasoning, he said: "For too long, we have made decisions based more on an economic compass, as if the use of one dollar has the moral equivalence of the loss of another... It is time we recognise money is merely a proxy for value, and at times, a very bad one."

Mr Seah, speaking in the parliamentary debate on the President's Address, called for a return to the the ideas of justice and community that informed policymaking at the founding of Singapore.

He asked the Finance Ministry to start a reform that will allow public officers to exercise discretion in recognising moral reasoning, instead of just price and cost, in crafting policies.

He acknowledged the dollars-and-cents approach had worked well in the past, leading to sustainable social, healthcare and housing policies.

But economic reasoning "is empty without a moral foundation", he said.

To illustrate his point, he cited the Education Ministry's move to charge teachers for parking at all government and government-aided schools from August.

The March announcement, which sparked public discussion and outcry, followed an Auditor-General's Office report which said educational institutions that let staff park for free was "tantamount to providing hidden subsidies for vehicle parking".

Yesterday, Mr Seah said that while teachers have accepted the new parking rules and moved on, "something still sits uncomfortably on this matter for me".

Citing teachers who bought stickers to stick on their students' worksheets and those who gave students a ride to school, he said they did not do these things with reimbursement in mind.

"It is laughable and an insult to think they do this in exchange for free parking... The withdrawal of free parking would not make teachers any less likely to do the many incredible... things they do.

"Rather, it is a reciprocity and a give-and-take which I feel we have lost by insisting on this strict calculus of benefits.''