In crafting my original world modelling of love, there was a blindspot due to the significant age of my relationships. Looking back in the long run, the power of shared experiences looks like a log curve, but the reality is that different experiences have different power and it only looks that way if you are thinking about your experiences unconsciously sorting them by power rather than chronologically. 

The general principle of the curve in the original article holds true, that as time in a relationship progresses you are more likely to have exhausted the powerful experiences earlier and gains will diminish (but are worth continuing to invest in to fight against decay!); but this is not all or nothing and relationships can surprise you.

I have to say, forcing myself to write this stuff out is really helpful in clarifying my thinking. Not only do you have to force your way through taking half-baked thoughts and instincts and turning them into something communicable, but once this is done you are able to let those half-thought through ideas go and properly build on them, rather than just ruminating over and over with the same level of depth.

It is from this newfound level of freedom that I’m able to realise something I was significantly off the mark on in my original post: the diminishing returns from shared experiences.

Shared experiences are a pretty big part of my overall framework, being one of the biggest actionable areas I identified you can target to increase the love in your relationships (and maintain them against decay), and yet I still got it wrong. This post is going to be my attempt to correct those errors, explaining how I came to make them, explore a little math and hopefully make the original model more robust (if still quite incomplete).

Power of love between different experiences

If I think of my life in general then compare with how much of it is made up of memorable and meaningful stories, it quickly becomes apparent that there are some very strong highs which quickly taper off into mediocrity and forgettable experiences. [I say this as someone who made a series of autobiographical vlogs and put significant effort into recounting these stories as best I could.]

In a more abstract sense, the “power” of any given experience in my memory appropriately follows a “power law”:

A simple power law distribution, following the commonly quoted “80:20 rule”

How memorable these experiences are is influenced by a multitude of factors, the biggest I see being:

1. Age at formation - As the brain reaches maturity, more and more can be remembered, but this is tempered by our diminishing ability to perceive time as we age. This means that memories formed in the ages 10-25 can have outsized importance in how we remember them;
2. Emotional intensity - The greater level of emotion attached to an experience, the more salient this is, be it a result of fear or joy. Some of the best bonding experiences I have had with friends has been in moments of Type 2 Fun because the stress in these periods made them so much more memorable.
3. Social norms - The importance placed on certain occasions within society can make them more memorable, for example weddings, birthdays, engagements. Because such events are well rehearsed in our memory through repeated exposure through stories, pop culture and experiencing others perform the same rituals, we are more easily able to integrate our particular experience of these events into our memory and with some of the leg work done in having a template to work from we are able to flesh out the finer details more precisely and with more power in our memories. Such events also benefit from emotional intensity, of course.

So at a base level that gets to how memorable events are, and how powerful they are at a personal level. When incorporating this into the idea of love benefitting through shared experiences, another key factor is the relational salience of these memories.

Relational salience is how likely you are to tie that memory with a loved one. For example, when I go snowboarding I always think of the friend who taught me, so there is a fairly strong element of salience associated with that experience. On the weaker (but still important) side, when I think of Homestar Runner (a web animation I watched as a teenager) there are tenuous links to various friends who I know have the same interest. 

A funny thing can happen with memories: their relational salience can be re-mapped over time simply by sharing them. As a child I was mauled by one of our family dogs; when my son was around the same age I told him that story as a lesson for why he needs to be careful around dogs. I suppose the power of the story stuck with him since he brings it up with me quite frequently and now I think of my son with affection whenever I think of the dog who mauled me, instead of whatever it was I felt before. I suppose this is probably a key part of CBT.

Shut up about feelings, I want the explanation of you being wrong

Right, fair enough then.

Given the premise that the power of experiences generally follow a power law, it makes sense that as these add up you end up with something along the lines of the below:

This is pretty similar to my original chart, but it depends entirely on the experiences happening in order from most to least powerful.

If instead a sampling of these experiences occur in a completely random order, you end up with something along the lines of these 2 charts:

Here the cumulative power is a lot less smooth, but the marginal increases do tend to somewhat decrease over time.

If you take this principle and further distort the random selection to bias earlier experiences (to take into the “Age at formation” effect) - you end up with an even more pronounced tendency for marginal gains as time progresses. 

Example of distributions across 5 relationships, each offset by 5 “experiences”

Per the above chart, in the long term relationships tend to eventually resemble the log-chart in my original writings. If you were to forget about the slow ramp up in building some relationships, the similarity to a log curve is even more apparent (the slow ramp up is most pronounced in Relationship 4). My personal experience tells me that it is indeed easy for memory to gloss of the early 'tenuously acquainted' phase of friendships, so this seems prima facie reasonable.

But importantly, relationships can surprise you - as seen in Relationship 3 above, which had several periods of marginal gains, interrupted by multiple step changes.

While the general principle of the curve in the original article holds true (that as experiences accumulate it becomes more likely that there will be diminishing returns), it is often worth continuing to invest in relationships to fight against your own forgetfulness and in hopes of the occasional step-change.