 The fourth mode (I.445b–c) offers a roughly Platonic criterion for being: those things contemplated by the intellect alone (ea solummodo quae solo comprehenduntur intellectu) may be considered to be, whereas things caught up in generation and corruption, viz. matter, place and time, do not truly exist. The assumption is that things graspable by intellect alone belong to a realm above the material, corporeal world and hence are timeless.