Probabilistic Morality, or: Ghosting On Spherical Cows

A Lighthearted Preamble

I have, of late, you’ll notice, been trying to find a date. In said pursuit, I have also begun using Tinder in an effort to hopefully delude some young woman into believing I am worth spending time with*.

I recently went on a nice date with a a nice young woman. Unfortunately, she… either doesn’t like talking to me, or is the world’s worst texter. We set up a tentative date, and I said “I can be there at 6?” — the question mark indicates that I was opening it up for her to confirm, deny, or choose a different time. She didn’t respond! When it came time for me to leave work, and I had to choose whether to go to the train or home, I finally had to follow up** and ask if that worked — and she quickly responded yes, we met at the decided-upon time, and had, I think, a nice evening.

So the next day, I followed up, saying I had a good time and asking about something she had mentioned she was working on while we were out. She didn’t reply! For over a whole day, she has not replied. Normally, I would take this as a clear sign that she was not interested, and in fact was doing what those damn Millennials call “ghosting.” But, as I said, she is already a forerunner for the World’s Worst Texter trophy. So maybe she did have a good time — she actually said as much while we were out! — and just does not reply to texts in a timely manner. Or, sometimes, at all.

A Bitter Aside

Dating sucks. Texting sucks. Finding oneself strategizing about texts to send hours or days in advance sucks. Everything sucks. Eat Arby’s.

Getting Towards My Actual Point, Insofar As There Is One

I was talking about all this with a friend of mine who has also been dipping her feet intermittently into the online dating game. I also mentioned that one time, after a date that I had enjoyed, I sent a similar followup text to the one described above, along the lines of: Hey, I enjoyed meeting you last night, would you like to hang out again sometime? <insert reference to a thing we talked about here***>. And she replied with something like: Hey, it was nice meeting you, but I’m not really feeling it, sorry. And I was all, Okay cool thanks for letting me know; good luck going forward!

And my friend here — the one at the beginning of last paragraph — was taken aback that a woman actually said that! It’s like getting a rejection letter after applying to a company. Nobody does that! She even thought that, hey, maybe she should try doing that too, when she’s not interested in someone, rather than ghosting.

But for a woman to actually straight-up turn a man down is often unpleasant, and sometimes even dangerous. When should a woman give a date an “official rejection” versus just ghosting on them? It’s clear that the woman should protect her own safety and wellbeing first of all, so texting a man who she did not feel safe with to begin with is a bad idea compared to disappearing. And giving a gentle but clear let-down to a man who is nice enough but you’re not interested in seeing again is a pretty clear good: you get to feel benevolent for being up front, and he gets to know where he stands and not to waste his energy pining over you. The advice seems natural: Err on the side of caution, but give a straightforward rejection whenever it feels safe.

Do You Even Remember The Title By This Point?

I started thinking about exactly what to do here. I started wondering what the correct course of action would be based on my poorly understood, utilitarian philosophy of morality. There’s two variables here: the woman’s (henceforth Alice) and the man’s (henceforth Bob) suffering****. We assume some things:

  • Alice has already decided not to see Bob again.
  • Bob would like to see Alice again.
  • Bob’s suffering is reduced by getting an explicit rejection as compared to being ghosted.
  • Alice’s suffering is reduced by offering an explicit rejection.
  • Alice’s suffering is, after deciding to offer the rejection or not, exclusively controlled by Bob’s response
    • If Bob replies in a positive or neutral manner, her suffering does not change (after the bump from magnanimously being straightforward)
    • The more negatively Bob replies, the more Alice’s suffering increases

I don’t think any of those assumptions are controversial: The first two are just an exposition of our hypothesis, and the rest seem straightforward.

For the purpose of getting anywhere, I am going to posit a final constraint that moves us into the world of spherical cows:

  • Alice has no priors to help predict Bob’s reaction

I think the idea holds up fine even if we allow Alice to have priors, but let’s assume she doesn’t for now. Bob is a spherical cow.

Maybe I’ll Present A Model Under This Header

Our assumptions let us assume fairly naturally that that Alice’s suffering will be increased by the value of some simple function*****.


The x-axis is the negativity of Bob’s response, and the y-axis is the effect on Alice’s suffering. So if he is positive or neutral, there’s no effect, then as he ramps up from “Okay, thanks” to “Wow, rude,” through “Fuck you, you’re ugly anyway” and on up to “You think you can just turn me down? I’ll fucking kill you,” her suffering increases. It’s not linear, its shape is not well known in general except that it is non-decreasing, but we can assume that it is “known” insofar as for any given response from Bob, we know the exact amount of suffering it causes in Alice.

But this function is not the end of the story. Because, see, what we actually have here is a probability distribution! Bob, for any given value of Bob, will only have one of these reactions. Over a large population of Bobs, however, we will find ourselves with some probability distribution over negativity of responses.

The Much-Awaited Conclusion

Once we have this probability distribution, we can wave our hands****** and come up with an expected value of Alice sending out a rejection text. The formula looks something like this:


Where S stands for suffering. So the total change in suffering, which is the sum of Alice and Bob’s changes in suffering, is equal to the suffering decrease of giving a rejection, plus the suffering decrease in receiving a response (these two are constants for our purposes), plus the suffering change based on the response that Bob gives.

Our setup gets us to this:


Which is to say: the expected suffering from Bob’s response is equal to the sum of suffering deltas of all responses times the probability of that response, multiplied by some normalization factor. So all we need to know is, given some suffering function from Alice and some probability distribution over possible responses from all Bobs, if


then Alice should send a rejection text. If the inequality is false, she should not.

To wrap up, I’d just like to say that I think it’s interesting that (for some model, anyway) a woman’s choice to do a rejected suitor the courtesy of actually telling him he’s rejected depends on two things: her own sensitivity to negative replies, and the probability distribution of how negative young men in the online dating world are when faced with rejection. That is to say, it is quite possible that today it is immoral to send a rejection text, but tomorrow the world will be a brighter place and men won’t be so fucking crazy, and it will become moral to reject them properly.


* It is not going great, so far. Thank you for your concern.

** Double-texting, despite being the Ultimate Sin of Thirst and Neediness, was my only option here besides giving up, so I reluctantly went with it.

*** I always worry that if I just say “hey let’s hang out again” I sound like I just wanna hook up, when, I mean, that’s something that’s totally cool, but not my primary goal, so I try to provide some sort of evidence that I was paying enough attention to be interested in my date as a person and not just a body, you know? I have no idea if this is effective; there are too many confounding reasons a woman might not want to go on a second date with me.

**** Suffering can be negative (what laymen refer to as “happiness”) but it’s easier to work with just one name for the quantity.

***** Simple here meaning: continuous, non-negative, real valued.

****** Do some calculus.☨

☨ I should really format my endnotes better.


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2 Responses to Probabilistic Morality, or: Ghosting On Spherical Cows

  1. SPC says:

    You need to add a term for Bob’s suffering. It may be, for example, that his suffering decreases with the harshness of his response. Also, it’s possible that he will send a message even if Alice does not explicitly reject him (his response to the empty message).

    • acorwin says:

      I don’t think your points change the conclusion, though. Yes, S_receiving should be expanded out to a probability distribution too, and S_response could be more accurately described as also containing the change in Bob’s suffering from giving the response. But I think that the assumption that Alice’s increase in suffering from receiving a negative response is greater than Bob’s decrease from giving it holds up in general.

      Anyway, since the model explicitly doesn’t give any real values at all, I believe my point remains: given Alice’s (very incomplete) information about any particular Bob, her choice of whether or not to send a rejection text is based on a best-guess probability distribution over all Bobs and their reactions (in terms of Bob’s change in suffering as well as Alice’s predicted change in suffering based on his possible response).

      I’ve received feedback from a couple people, and I definitely think this post was not well-structured, and did not make it clear enough that all I was trying to get at is the idea that a singular decision can be “moral” or “immoral” based on a probability distribution. I think I’ve demonstrated that consequence, though, despite all the other problems.

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