  The usual interpretation of the modes of infinite regress, reciprocality, and hypothesis, is that they codify Sextus’ condemnation of each of these three forms of argument. So, in by far the best and fullest treatment of the Five Modes to date, Barnes 1990a, we are told that Sextus thinks that infinitely regressive arguments are ‘bad arguments’ (1990a: 43). To be sure, ‘Sextus usually leaves unspoken the thought that infinite regressions are Bad Things’ (44), but, says Barnes (ibid), Sextus does offer us one reason for why they are bad: ‘we have no point from which to begin to establish anything’ (PH I 166). The interesting philosophical question here is this: why should recognition of a bad argument for the conclusion that P encourage us to suspend judgment on whether P? If I argue that the world will end tomorrow on the grounds that Nostradamus says so, your recognition that this is a terrible argument for its conclusion hardly makes you suspend judgment on the question of whether the world will end tomorrow! Barnes’ answer is this: 