Platonists have tried to respond to this argument in a few different ways, but the most popular (and, it can be argued, the most plausible) response is to try to undermine the inference from (i) and (ii) to (iii) by explaining how (iii) could be false even if (i) and (ii) are true—i.e., how human beings could acquire knowledge of abstract objects despite the fact that they are causally isolated from such objects and, hence, do not have any information-transferring contact with such objects. This