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The following example is from The Only Skill That Matters, where memory palaces take up an entire chapter. Thus, this summary is highly condensed. It illustrates the idea of a memory palace very elegantly. I’ll reproduce it in my own words, but all credit goes to Jonathan Levi. (His explanation is much more extensive and detailed than mine, but I wanted to explain it in my own words and give you a reason to read The Only Skill That Matters for yourself).
Picture yourself standing in the doorframe of your childhood bedroom. To your left, there will probably be some piece of furniture, maybe your bed, a desk, or a wardrobe. Imagine 2 seahorses on whatever piece of furniture it is, during a heated lovemaking session, while they’re being sucked up by a vacuum (no kink shaming). Then, moving counter-clockwise to the next corner, you might have some furniture there as well, or some other stuff. Picture it as if someone had thrown a bucket of chunky, sticky peanut butter over everything. There is a huge, brown, kind of disgusting-looking mess there. One corner further, add a bunch of cables to whatever there is. They’re coming out of every nook and cranny, twisted and tangled, like they’re a parasite wrapping themself around a host. And then, in the last corner (assuming you’ve had a typical 4-wall bedroom), your favorite picture is hanging on the wall, in a beautiful, glamorous frame. The frame is highly detailed, elegantly crafted by a skilled carpenter. Finally, in your doorframe, there is a huge pin like the ones you’ll find in a navigation app. It’s so big that it’s blocking most of the door and you’d have to crawl underneath it to enter or leave your room.
Revisit the corners and your doorframe again. The seahorses who got caught by a vacuum while doing it, the greasy, chunky peanut butter smeared across the wall and whatever furniture there is, the cables coming out of everywhere, densely twisted and tangled, your favorite picture in a beautiful frame, and the giant map pin. The seahorses represent your two hippocampi, which like to clean out your memories (vacuum). The chunky peanut butter means that you should “chunk” information into one memory palace, so you don’t get confused about which one you put it in. The cables represent the “what fires together wires together” saying, meaning that you should connect new information to existing ones. Your nicely framed favorite picture represents visualization as the backbone of memory palaces. You’re encouraged to create bizarre, shocking visualizations, as they’ll stick around better. And finally, the map pin represents the memory palace itself, and your highly evolved spatial memory. Use known locations as your memory palaces for different topics.¹
Memory palaces utilize the strong spatial memory of the brain. You’ll likely be able to mentally navigate dozens, if not hundreds, of places you’ve been to. Exploring what places I could vividly remember has been quite interesting for me, as I was surprised by how many there were. It should be no surprise that I can easily reconstruct my old grandparents’ house, even though I haven’t been there for several years, because they moved to another place. But I also remember places with much less emotional attachment, if any at all. The route I used to cycle to school every day, the grocery store near my old apartment, the central station of a city I lived in, or even a cinema I went to a few times. I haven’t made a list, but I’m quite sure that I won’t have a shortage of places to use for memory palaces anytime soon.