There is a religious obligation in Mormonism to proxy baptize one's non-Mormon ancestors so they can get into heaven
Not quite right. Proxy baptism simply allows an individual recipient the opportunity to accept or reject the teachings if they didn't get a chance to learn about them during their lifetime. There's nothing passive or automatic about it.
I fail to appreciate any material difference given that the individual is dead and utterly incapable of accepting or rejecting anything.
If you're expecting a non-passive response from these ancestors, I'm afraid the whole endeavour is a total waste of time and energy. See definition of dead for details.
The idea that proxy baptism for the dead has any effect is predicated on the belief that there is an afterlife and that the individual has the ability to accept or reject the ordinance.
Not really, a proxy baptism might make those still alive feel better about themselves or their ancestors, and of course it solves one of the theological conundrums of purgatory.
My point is that the dead are dead, no matter what anyone of any belief chooses to think. Just because a group of people think or believe something doesn't actually make it so.
I guess they have a fax machine or something in a corner in some room in SLC? Or maybe some sort of special courier service to ferry the communiques to the various other-denominational Heavens? A really secret interoffice mail envelope?
I mean at a certain point doesn't this just turn into grown adults playing pretend?
> given that the individual is dead and utterly incapable of accepting or rejecting anything.
In Mormon (& indeed, most Judeo-Christian-Islamic belief), the state of dead might be defined as "Transferred to different plane of existence, still a cogitating being".
Not quite right. Proxy baptism simply allows an individual recipient the opportunity to accept or reject the teachings if they didn't get a chance to learn about them during their lifetime. There's nothing passive or automatic about it.