If you want to disprove—or at least throw whatever the quantum tech industry’s equivalent of a monkey wrench is into—current conceptions of God and the soul, prove time travel. For time travel is not compatible with the notion of an indivisible soul, particularly if that soul is en route to an eternal afterlife of punishment or reward.
Imagine going back in time five minutes to face yourself. Would both of you have your soul? You might concoct some solution here—maybe about the soul actually dwelling outside the body and being somehow able to perform its metaphysical duties across time and space within multiple bodies simultaneously. After all, we go through one body after another in a lifetime, but the soul stays the same, and is what makes today’s me the same person as that bouncy little infant from decades past; many bodies, one soul.
This sort of ad hoc gerrymandering is what got us our present notion of the soul. Over the centuries, serious thinkers have relentlessly tweaked the idea in an attempt to accommodate changing conceptions of God, and in an effort to temper the ever-building discord between ancient theological frameworks and advancements in philosophy and science. Over time, the soul has gone from maybe (or maybe not) immortal, to definitely immortal (thanks, perhaps, to Egyptian influence), and has become the metaphysical (though ultimately unsatisfying) explanation for many of our most inscrutable observations about the human situation. Consciousness, bodily mobility, and personal identity among them.
But such ad-hocery won’t save the time traveler who’d like to posit the soul outside the body. For one thing, you’d need to explain why that soul attaches itself to that stream of bodies rather than jumping from one stream to another, but this gets us into the territory of personal identity, a thorny mess unrelated to time travel and best left for another day. You’d also need to explain soul and body interaction. I’ll leave that alone here as well. Instead, here’s a thought experiment about time travel.
Ben was an elderly man who, just yesterday, passed away after decades of sinful choices. God, in His infinite and infallible wisdom (and apparently forgiveness, etc.), has condemned Ben to the eternity of hellfire that he deserves. But now suppose a young woman, Sarah, travels back in time from our distant future, and has a chance encounter with Ben as a young man. She meets Ben at a critical moment in his life, altering his circumstances so that he heads down a path of righteousness, rather than one of damnation.
Some questions. When Sarah met Ben, are we to believe that his soul was simultaneously burning in hell AND serving its duties within Ben, alive and better than ever on Earth? And, after having lived out this better life, will his soul then reside both in heaven AND hell, so that he simultaneously enjoys heavenly exaltation AND suffers unspeakable infernal torment?
Remember, God’s infallibility suggests that He would not change His verdict, moving Ben’s soul from hell to heaven, or back to Earth (along, I presume, with the soul of every other being alive at that moment). Indeed, according to some philosophers (St. Anselm and Leibniz come to mind), God is bound to always making the correct (or best) choice (an observation, by the way, meant, at least by St. Anselm, to strengthen the perfection of God’s free will, rather than limit it).
Nor would it do to suggest that Ben was destined for hell to begin with, and so will always end up there. This eliminates the critical element that makes God’s condemnation of Ben just: Ben’s ability to choose which path to take. Without human free will, God becomes a tyrant. Even Calvinists believe in free will, after a fashion. (Though, again, Leibniz’s picture of God having chosen to create the best of all possible worlds is in part a [highly unsatisfying] response to this.)
Thus we see that time travel is incompatible with the existence of an immortal, indivisible soul, particularly if its fate rests in the judgment of an all-mighty and just personal God.
Perhaps, though, time travel itself is the problem. Perhaps, for example, souls don’t move around in the same four-dimensional spacetime as bodies do. So, were I to go five minutes back in time, I wouldn’t encounter myself. Or at least, not myself with a soul. Perhaps I’d only encounter a zombie version of myself: a body going through the motions of an immutable past that’s furnished with equally soulless rocks, trees, and buildings.
Or perhaps to travel through time isn’t something that can be done in the way we conceive of it, because objects progress through time as single instances. In other words, there’d be only a single instance of any object, regardless of its relation to any timeline. So, were I to go five minutes back, I wouldn’t encounter myself at all. I wouldn’t encounter my house either, or any other material objects, as they have moved on to—or along with—the present. I would encounter nothing, or some version of nothing. Consider it this way. If I traveled 100 years into the future, whatever I encounter there, I wouldn’t be able to say that I’ve gone to a time after my death, because there I am, still alive.
I don’t know how to align any of this with interpretations of special relativity in which there is no distinction between past, present, and future. Furthermore, from a theological perspective, if the impossibility of time travel was part of God’s design, one gets that vague sense that, for God to disallow time travel—and thus a plethora of otherwise naturally available choices—on the basis of conundrums such as these, would be effectively little different than removing Ben’s free will altogether.
But no matter. This is all just a bit of fun anyway, because souls don’t exist, and time travel isn’t possible.
Of course, one can continue indefinitely with the ad hoc assembly of new conceptions of the soul and God, on the grounds that “we don’t really know what’s out there.” I would agree with this declaration of ignorance, and would, in fact, list it among the reasons I don’t believe in souls, God, or anything else that falls under the loose class of things deity related. For, in order to disbelieve or be agnostic about something, I must know what it is that I’m disbelieving or being agnostic about. Tell me precisely what it is I’m meant to accept or reject, and why I should take seriously that supernatural theory rather than the many billions of other equally possible ones, and I’ll give it some thought.
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(Note to self: One day, pull a play or dialogue-driven short story out of this [see notes elsewhere for opening paragraph and synopsis; don’t forget to work out how a good person could encounter a corrupted version of herself a mere twenty-four hours in the past; through the collaboration, perhaps, of a forgotten acquaintance and a third instance of herself, both of whom have sneaked in from five years hence?]. Inspirations include Daniel Dennett’s “Where Am I?”, Woody Allen’s short plays [e.g., “Death Knocks” and “God”], and Shane Carruth’s film, Primer.)

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