In the 1840s Karl Marx wrote that social revolution would involve "carrying out the thoughts of the past," in which "humanity begins no new work but consciously completes the old work". The role of revolutionary thought for Marx, in other words, involved drawing attention to how past revolutionary tasks were failing to be worked through in present political practice; of understanding the reasons why theory and practice had changed and, in turn, how this understanding could be advanced towards the (present) completion of the (old) revolution.
What does it mean today when the challenges to the status quo are no longer clearly identifiable as originating from the Left? While it seems implausible that Left ideology has been transcended because people still explain social currents in terms of Left and right, there is a sense in the present that to end exploitation will demand a measure of realpolitik—a better tactical response—rather than ideological clarification. One has the uneasy feeling that existence of the Left and the right only persist by virtue of the fact the concept of the Left has somehow become settled, static, and trapped in history. But wouldn't this be antithetical to any concept of the Left?