- Humans in heaven will eventually have a personal love for all persons.
- It is not possible for a human to have a personal love for infinitely many persons.
- Therefore, there are only finitely many persons.
Let me clarify the premises. I mean the "all" in (1) and the "there are" in (3) to extend to all persons who ever exist--my quantifiers are eternalist ones. I mean "personal love" to contrast with the kind of "impersonal love" that even now the saints among us have towards all humans (and maybe even all persons) in general. A personal love, however, is a deeper relationship that requires an attitude directed at one specific person. An argument for (1) might go as follows: humans in heaven will be morally perfect and hence they will have a love for all persons. Now moral perfection doesn't itself require anything more than a general love--for it doesn't require anything more of us than we can have in this life, and in this life we cannot personally know billions of people. But while moral perfection doesn't require that the humans in heaven have more than a general love for all persons, when we have the right kind of general love for a person, we want to know the person specifically, to know the specific good features of that person, and in heaven such desires will be satisfied. So (1) is true. The argument for (2) involves either the finitude of our minds or something like my causal finitist thesis.
Presentists (and maybe some others) might want to replace (1) by the weaker claim that humans in heaven will eventually have a personal love for all persons who then exist. If so, then if we add the additional premise that all persons live forever, we get the weaker conclusion that at every present and future time there are only finitely many persons.
Some may worry about hell here. Do the people in heaven have a personal love for all the damned? Do they really know and delight in what good can be found in them? I would like to say "Yes". I can imagine someone, however, saying that (a) such a personal love for the damned would lead to mourning and (b) that mourning has no place in heaven. I would deny (a), I guess. But I can see that some people would find this line of thought implausible. Very well. Then I can revise premise (1) to say that humans in heaven will eventually have a personal love for all persons in heaven. And then the conclusion is that there are only finitely many persons in heaven. I can still, however, get the conclusion that there are only finitely many persons if I add the premise that if there are infinitely many persons not in heaven, then there are infinitely many in heaven as well. (It would be too tragic if infinitely many went to hell--or, worse, were annihilated--but only finitely many went to heaven.) Since there are finitely many in heaven, there are finitely many outside of heaven.
If one adds to the original argument the premise that one can only have a personal love at t for someone who exists at t, then (1) on the eternalist interpretation also yields the important thesis that all persons live forever.