 More modifications may be required. First, strictly speaking, on this characterization, presentism is a thesis that denies the existence of atemporal or timeless entities, that is, entities that aren’t present (but aren’t past or future either, because they are not in time). This appears to rule out the existence of abstract entities, on the presumption that abstracta are timeless. [See the entry on   abstract objects .]  This also appears to rule out the existence of a timeless god, which is problematic for those that accept “divine timelessness” or “divine atemporality”. [See the entry on   eternity in Christian thought,  esp. §4.1.] One or both of these may be a step too far for some presentists. Hence, we might be pressed to modify P and restrict it to concrete or physical objects. We’re not forced to make that move, however, since P only rules out such entities insofar as they are understood as timeless. Presentism is compatible with the existence of abstracta, for instance, so long as such entities exist now (exist within time). In any case, timeless abstracta are inconsistent with P, but (as is clear) this needn’t be of too much concern. It is unclear how much would be lost from the core of presentism if we coupled P to timeless abstracta or a timeless god. For some discussion of additional problems with combining presentism with divine atemporality, see Leftow (2018).