Should governments run deficits to pay for ‘stimulus packages’? ‘Of course!’ say many Democrats, liberals, socialists and others who flatter themselves that they are ‘progressive’. ‘Heaven forbid!’ say many Republicans, libertarians and others in the USA and Canada who like to think of themselves, quite wrongly in some cases, as ‘conservative’. On occasion, these opinions, whether ‘left’ or ‘right’, may rest on some understanding of how a market economy works. But all too often, it seems, they are mere gut reactions—nothing but the result of prejudice and ideological bias.