On the Nature of the Mer-Soul: A Question

(Yes, I am here again, and I will wring a happy ending out of this story if it kills me.)

Per her agreement with the Sea Witch, the Little Mermaid was to receive legs and a human soul in exchange for her tongue, contingent on her marriage to the prince. The direct physical exchange, tongue for legs, was made on the spot.

Both legs and the potential soul were cancelled in favor of sea-foaminess upon her unequivocal failure to marry the prince, i.e. his marriage to someone else.

Now, my question regards that potential soul—namely, is it indeed potential, or an item of actual existence? Did the exchange go tongue for legs, marriage for soul? Like a pay half now, pay half when the job is done kind of deal?

In that case the Little Mermaid would be a mermaid with legs until her marriage, at which point the soul would kick in and she would be human.

Alternatively, it may have happened all at once. For the price of just one tongue, you too can experience legs and soul for an unlimited time! (Fine print: Prices and shipping may vary. Only valid at participating locations. Final purchase dependent on successful completion of wedding ceremony. Side effects may include, but are not limited to, death and transformation into sea foam.)

In this case, the Little Mermaid would actually be a Little Human from her arrival on land right up until her untimely demise.

Then the question becomes, if the soul was ever present, when exactly did it depart? Did it cease to exist the moment the prince said “I do”? Or did it happen when the rest of her turned to sea foam?

And then we must consider the nature of the soul itself. The story has confirmed that souls may be created; does this mean that they may also be destroyed? But the text does specify, on multiple occasions, that we are dealing with an immortal soul. So our final question is, if the soul comes into existence at the same time as the legs, does it go poof when things take a turn for the foamy, or does it, true to its immortal nature, go up into Heaven while the body goes down into the sea?

(This is all, of course, being considered in light of the version where the mermaid dies, rather than the one where she becomes a Daughter of the Air and spends a few centuries earning a soul; that version opens up a whole slew of theological issues in regards to faith vs. works. We don’t have time for that. Maybe next week.)

And in the end, it all comes down to what it always comes down to, for me, when we talk about The Little Mermaid. Does she get the better end of the deal? Can we count this as a happy ending?