"Keynes accepted capitalism, but without zeal or sanctimony. He was mainly concerned with assuring its immediate stability, not justifying it sub specie aeternitatis. This prevented him both from ever becoming an official ideologue of the status quo like so many economists, and from developing a deeper and longer dynamic perspective. His contemporary Kalecki, who unlike Keynes was familiar with the work of Marx, achieved some of the same countercyclical insights, albeit in fragmentary form, but saw the ulterior implications of them. By reinserting Keynesian categories into a rudimentary political economy, he was able to predict what he called the 'political trede-cycle', which has since become the principal economic contradiction of advanced capitalism: the conflict between full employment and stable prices."