I'll stop short of endorsing the idea that soulmates exist, but I will advance the argument that Randall gave up easy on this one.
The one firm assumption that we're making is that every person has a single, unique soulmate (the soulmate may be someone who is already dead or has yet to be born).
Other assumptions can optionally be added (or not), for example:
- homogeneity requirement: only humans can be soulmates of other humans (if you want to generalize, any soulmate-capable species can only be soulmates with members of a species which is capable of mating with the first)
- duality requirement: a soulmate can only be of the opposite gender (the gay and TG community would obviously take issue with this, so I suggest it not for that reason, but because added constraints can make matching problems more interesting)
- coinciding existence requirement: the lifespans of a person and their soulmate must overlap at some point
- awareness requirement: a person must in some way come in contact with or be concretely aware of their soulmate during the course of their lives (the possibility of infant mortality would necessarily complicate this requirement)
A person may die as an infant or a child, and a person may have multiple classical relationships (with children from more than one). Therefore, a classical relationship cannot be either a sufficient or necessary condition for being a soulmate.
Let a society be some set of people, including possibly virtual people (ones that have died or have yet to be born). A soulmate matching
is a matching in which every person p
in the society has a unique, distinct soulmate p'
, who is also part of the society. A society is soulmate feasible
if a soulmate matching exists for that society.
The originally posed question refers to the possibility that everyone has exactly one randomly chosen soulmate. I'd argue that a stronger interpretation of the question is one where society persistently maintains a state of soulmate feasibility. At that point you can begin to introduce quantum arguments, as in: given a soulmate feasible society, take the set of all possible soulmate matchings for that society. The society has a soulmate state which is the superposition of all soulmate matchings (ie a combination of all of them with probability weightings for each individual one). If a pair of soulmates is ever affirmed, then the state collapses to only allow matchings which are still consistent. Thus, this model guarantees that people who have found their soulmate are represented as such, some people may never actually find their soulmate, but a soulmate always exists for any individual, among a set of possible candidates.
I'd argue that there's no reason to write off the chance of soulmate meetings on the basis of pure chance, because it dismisses the possibility that a pair of soulmates, by virtue of being soulmates, share an intrinsic characteristic which would lead them to gravitate towards each other. For example, look at the way that most of the brightest physics minds which pioneered the atomic age also happened to be colleagues. If you want to get esoteric, you could point to the fact that miniature wireless phones exist, and use that to argue the possibility of some sort of unconscious telepathy which actively homes in on a soulmate.
Ultimately, the biggest hurdle to an analysis of soulmates is the fact that it's inherently unverifiable - only the person in question and their soulmate actually know for sure that they're soulmates, and it's a sense that is easily deluded (ref: the vast majority of teenagers).
Disclaimer: obviously I don't see thread-necromancy as an authoritative objection, especially with the book now in print.