Recently, Facebook resurfaced an old photo of mine, taken in 2009. Really, it is an unremarkable photo, just me and three friends sitting around playing video games. And yet I couldn’t stop looking at it: my friend’s old apartment, another friend’s old haircut, the Asics in which I ran my first half-marathon. Every boring detail in this ostensibly boring photo was captivating.
Look, I get it. The point of the On This Day feature, the TimeHop copycat that was rolled out earlier this year, is that Facebook wants to remind people how much they used to like using Facebook. This is especially important considering that, last year, Facebook was the only social-media site to lose active users. Oftentimes (most times?), Facebook’s attempts to woo their user base back is cringe-worthy. (See: The faux-intimacy of its chirpy “Good morning!” greetings, or 2014’s Year in Review, which cruelly suggested some parents reminisce about that time their child had died earlier in the year.)
Conversely, the reaction to On This Day mostly hasn’t made people angry. Mystified is more like it. “Very rarely does anyone post something worth noting on Facebook,” wrote Sarah Hagi for GQ last month, “making the majority of your ‘memories’ useless and confusing.” I agree. And that’s exactly why it’s genius.
If you’re skeptical, I’m not surprised, and neither is Ting Zhang, a Harvard Business School professor and author of a 2014 paper published in Psychological Science on the “unexpected value of rediscovery.” In it, she and three Harvard colleagues argue that people underestimate how much joy they’ll get by revisiting memories of perfectly ordinary moments from the past. For one experiment, Zhang and her co-authors asked people to prepare a time capsule, including things like a recent photo and a short essay about a recent conversation they’d had. They were also asked to estimate how interested in these mementos they thought they’d be in the future. Three months later, they were given the opportunity to dig into those time capsules, and the memories meant more to the study participants than they’d expected.
Similarly, in another experiment, researchers asked students who were in relationships to either write about how they’d spent Valentine’s Day, or how they’d spent an ordinary February day together. Like the previous experiment, they were also asked to estimate how interested they thought their future selves would be in recalling the memory three months later. And, once again, most of the participants underestimated how excited they’d be to read their own scribblings — but, interestingly, those who’d written about the ordinary day were more curious and interested in revisiting their memories than those who’d written about Valentine’s Day.
People like to think their minds are better at hanging onto memories than they really are. It seems impossible that you’d forget something you currently see or do all the time; likewise, if something is common enough to seem mundane today, surely it will seem equally mundane a year from today. But human memory is imperfect, and although in the moment it didn’t seem like you could possibly forget the details of the friend’s apartment where you spent so much time in your mid-20s, you probably did.
The Harvard researchers call this and their discovery that people enjoy revisiting those ordinary moments more than they expect a “novel error in affective forecasting: failure to anticipate the pleasure of rediscovering past experiences.” As a friend wrote the other day after sharing a years-old status update (remember when people regularly updated their statuses?), “love that my old self can speak into my current life.” It’s a little wave hello from a past version of you, one you didn’t even realize you’d forgotten.