Economist: Global recessions can never be prevented, for they could be prevented only if they were predictable. Yet economists, using the best techniques at their disposal, consistently fail to accurately predict global recessions. The economist's argument is most vulnerable to the criticism that it ['presupposes in a premise the conclusion that it purports to establish', 'fails to establish that economists claim to be able to accurately predict global recessions', 'fails to address the possibility that the techniques available to economists for the prediction of global recessions will significantly improve', 'implicitly bases an inference that something will not occur solely on the information that its occurrence is not predictable']