 The second strategy that platonists can pursue in responding to the epistemological argument is to argue that (2) is false and that human beings can acquire information about mathematical objects via normal perceptual means. The early Maddy (1990) pursued this idea in connection with set theory, claiming that sets of physical objects can be taken to exist in spacetime and, hence, that we can perceive them. For instance, on her view, if there are two books on a table, then the set containing these books exists on the table, in the same place that the books exist, and we can see the set and acquire information about it in this way. This view has been subjected to much criticism, including arguments from the later Maddy (1997). Others to attack the view include Lavine (1992), Dieterle and Shapiro (1993), Balaguer (1998a), Milne (1994), Riskin (1994), and Carson (1996).