To claim that we are staring down the barrel of another Great Depression is simple nonsense. Yet it is not as absurd as another ploy popular with advocates of stimulation: namely, counting its costs among its benefits.

Mr Brown plans to fund his stimulus package (in fractional part) by increasing the tax rate on income over £150,000 from 40 per cent to 45 per cent from 2011. On average, those affected will pay an extra £3,150 a year.

In her Guardian column, Polly Toynbee celebrated this as a step in the direction of "social justice". By her reckoning, Mr Brown's stimulus package has two benefits: it will ameliorate the recession and it increases the amount of tax paid by the rich. She counts the average loss of £3,150 by those in the top one per cent of income-earners among the policy's benefits. Toynbee insists that the rich deserve to lose this money and perhaps she is right. But a deserved loss is still a loss and thus a cost of the policy. She is muddling moralising and accounting.

Few are as keen on taxes as Toynbee. But almost everyone is keen on employment, and this may explain the near-universal tendency to count job creation among the benefits of the stimulus package. To see why it is not, suppose Mr Obama pursued his Green New Deal idea and spent billions of dollars on building wind farms. The benefit of this would be the wind farms that are built, not the employment of those who build them. The employment is part of the cost. If those same wind farms could be produced with less labour, America would be better off. The labour saved could be deployed elsewhere to produce other valuable things.

New Deal-style infrastructure projects may be a good idea, as may be taxing the rich after 2011 to fund consumption today. But you cannot properly defend such policies by pretending that their costs are actually benefits, nor by massively exaggerating the dangers we face and, hence, the value of a stimulus package that avoids them. The economic decisions being taken by our leaders are extremely important, yet the rhetoric surrounding them is fatuous. Though not surprising, it is disgraceful. For, as Mr Brown might put it, serious actions require serious justifications.