That's a lot of "you" which doesn't necessarily apply to all readers, and needlessly weakens the whole post when even a few of the assumptions are obviously wrong.
I personally conceptualize subjective time as deltas in experience. I get more subjective time for the same wall time when I'm doing something that makes me have new thoughts worth remembering, compared to when I'm doing something that's a repeat of familiar experiences.
Your advice to imagine everything having changed/aged, before gathering evidence that it's done so, strikes me as likely to create more of the bad kind of "my assumptions were wrong" surprise than simply updating with real new observations when acquiring them. For instance:
I experience writing the year as something that happens on autopilot. For 11 months, the shortcut of using a hardcoded number instead of recalculating which year it really is saves a lot of cognitive effort. The cost of this shortcut is a bit of struggle while overwriting the old value in that cold storage, but I choose it over the alternative.
The reason I'm surprised by infrastructure changes is because they happen relatively rarely. If I imagined/predicted that every street, park, and landmark would change between every time I visit a place, my predictions would be mostly-wrong. When I imagine that most stuff won't change but a few things might, my prediction will be mostly-right, and I'll update based on observing which things changed. I experience the surprise/curiosity of "what did they change this to?" as an important part of adding emotional weight to performing the right update quickly and accurately.
Usually when I'm surprised by how someone has aged, it's not the fact that they got older, but that the series of choices/experiences shown by their aging has shaped them in a direction that I wouldn't have expected based on what I used to know about them.
For instance, I fondly recall an acquaintance I haven't seen since in a decade who was quiet, bookish, and surprisingly skilled at making tie dye. If I ran into him today, he would certainly have aged; that's not what would surprise me. There are many new experiences he might have had in the intervening decade, which would show in his appearance: Maybe he got into business, and now wears suits instead of t-shirts and cargos. Maybe he chopped his long hair off, or dyed it. Maybe his circumstances have changed for the worse, and now he looks unhealthy and unkempt. He might have gained weight, even lots, or taken up fitness as a hobby and gained muscle, or encountered health challenges and lost a lot of weight, any of which would change the appearance of his face as well as his body. Regardless of how this acquaintance has changed, the surprise isn't that there were changes, but which changes there were. Whatever direction he's changed in, it'll tell me more about who he was a decade ago as well as who he is now, because who he was before turns out to have had the capacity/proclivity to live the lifestyle I see side effects of in his appearance today.
In short, the surprise isn't that the changes happen, but which changes one sees, out of the myriad possibilities.
I've encountered a lot of old once-state-of-the-art gadgets while organizing my stuff lately. Other than the natural decay of battery life and occasional disappearance of required peripheral infrastructure, their core functionality basically doesn't change. The surprise is not that my old iPod worked as an iPod and basically still does, but that my current phone does those same things and so much more. If my desires for features change, that's because I changed, not because the stuff did.
Remembering the moment when that iPod was the best portable music player in the world, and comparing it to the moment when my phone is basically tied for the best at being a pocket supercomputer in the world, helps me greatly with predicting what it'll look and feel like in another couple decades when my 2024 tech compares unfavorably to the state of the art.
no one ever stops to wonder how the specific day it is today is a foreign world.
Foreign to whom? The present moment is the only truly non-foreign world to us as denizens of linear time. Today is foreign from the perspective of tomorrow or yesterday, but we as we are in this moment don't exist tomorrow and didn't exist yesterday. Although the perspectives from which today is foreign matter a bit, I don't think it's a good idea to privilege them over the perspectives from which today is domestic.
(Note: Yes, I[1] know this post is nine days late. It's still the early into the first month of the year, so I guess it still counts! Also, I'm not very good at wordsmithing.)
Why are you often surprised at the passage of time?
First of all, time is always passing. You should know that already. Since everything changes when time passes, everything is always changing.[2]
That said, there is a common phenomenon, where you are often surprised by the passage of time. This is because the way you think about the world is often static - or, in more rationalist-esque terminology, you are caching your mental models. More precisely: when you see, hear, or read of something, you usually don't think, "This is what [thing] was like at [time]". More commonly, you just think: "This is what [thing] is like". Then, when you revisit this particular thing, you notice that it's different from what you remember, and feel a pang of surprise. But you predictably felt surprised because you forgot to think about how that thing may have evolved since you last visited it. I call this "being surprised by the passage of time".[3]
Here are some examples of the thing I'm trying to get at the spirit of:
The new year, and how to not be surprised by the passage of time
New Year's Day is a celebration of the new year, and we all celebrate it.[5] But I propose that it is really a celebration of the passage of time - and, by extension, a celebration of the virtue of not being surprised by the passage of time.
How should you celebrate New Year's Day then? Update your mental models. Envision yourself, right now, sitting with a calendar reading "2024" (or whatever your current year is)[6] prominently hanging over your head. (This is an order! You're doing an impromptu rationality exercise.) Imagine your friends waking up, yawning and stretching their arms as the morning sunlight breaks through into their bedrooms yet again, in the year 2024. (They should be all older, and potentially also weirder, than how you last remembered them.) Imagine your favorite celebrities - Joe Biden, Kim Jong-Un, Gwern Branwen, whoever the hell you care about - waking up - all realizing that their calendars, their priorities have to keep shifting - in the year 2024. Imagine your favorite companies or organizations all collectively adjusting and vibe-shifting into the year 2024 - professors at Harvard or MIT, spies or analysts at NSA, diplomats walking the UN's global corridors, whatever you happen to be thinking about or be part of right now.[7] Hell, even imagine your stuffed animals or toys living into the year 2024, battered, bruised, and/or forgotten as they might be, if that helps you adjust to life in the current year.
If you were wondering - yes, you can do this rationality exercise on any day, not just on New Year's Day (or Eve). Why then, do I suggest you this on New Year's Day? It's because everyone celebrates it! This New Year's Day 2024, everyone is forced to struggle conceptualizing the year 2024 - a foreign world which the world is collectively plunged into - and leaving behind the relatively familiar old year, the year 2023. By comparison, even though every other day is also a foreign world, no one ever stops to wonder how the specific day it is today is a foreign world.[8]
Thus, I suggest that this rationality exercise is better when done together - in a rationalist meetup or local group, for example.
Happy New Year 2024, LessWrong!
Footnotes
"I" refers to duck_master, but I gave Aléa a token coauthorship (to proofread this post) because she asked me nicely on Discord (though ultimately she did not make any suggestions). Also I asked ChatGPT about this post as well out of curiosity, though I didn't reuse its output.
Strictly speaking, this is not quite true. Many things (eg streets, words, or historic landmarks) can remain essentially unchanged for decades or centuries. For many other things (eg video games, wikis, construction projects), any changes are discretized into isolated incidents separated by varying gaps, rather than a continuous unending flow of change. However, I don't think this difference really matters that much for practical purposes.
This is somewhat of a cryptic or mystical phrase on its own, so I suggest using it as a sazen (in Duncan Sabien's sense of the word).
See various blog posts 1, 2, 3 that I just googled. If I recall correctly, I think some rats/postrats have also tweeted about this phenomenon as well (though I can't find such tweets right now).
Probably not every single one of us, but I don't want this to get in the way of saying things poetically.
Since I'm writing this post in January 2024, it's primarily targeted to people who have to get used to being-in-2024-rather-than-in-2023. If you are reading this in 2025 or later, substitute mentions of "2024" with mentions of your own year.
Disclaimer: I'm a student at MIT, have occasionally visited Harvard, and once emailed Gwern years ago; I have no other connections to any of the other famous institutions or people mentioned.
Except, perhaps, for monks or mystics, for which "contemplating the mysteries of each new day anew" can become just another Tuesday. Also, sorry for the rather facetious footnote; I can't figure out how to get rid of any of them in the LessWrong post editor.