Using a memory palace to memorize a textbook.

DirectedEvolution19 Jun 2020 2:09 UTC
62 points
16 comments6 min readLW link1 review

I spent the week prepping for finals. One is a year-long cumulative closed-book chemistry exam that I haven’t had much time to practice for. I was worried about memorizing a few things:

  • Periodic trends and exceptions

  • The form and application of approximately 100 workhorse equations and various forms of measurement (molarity vs. molality vs. mole fraction).

  • Equations that get used rarely in homework or on exercises, but might be used as “gotchas” on the test.

  • Some concepts that I found either confusing, or so simple that I didn’t bother to remember them the first time.

My anxiety wasn’t just my ability to recall these ideas when prompted:

“What’s the two-point form of the Clausius-Clapeyron Equation?”
ln(P2 /​ P1) = - Δ Hvap/​R * (1/​T2 − 1/​T1)

Nor was I unable to perform the calculations.

My real concern was that I had spent the year treating my chemistry textbook like a reference manual, a repository for concepts and equations that I could look up when needed. I just memorized the few bits I’d need on any given quiz. Looking back at 1,000 pages of chemistry, I foresaw myself reviewing chapter 5 for a couple hours, but forgetting that review by the time I got to chapter 19.

The sheer volume of work that seemed to be involved in memorizing a textbook seemed unreasonable. I hate using Anki, and I spend far too much time in front of screens as it is.

So I decided to try something different—experimenting with the memory palace technique.

I perceive myself as having a poor visual imagination, but I’ve been trying to practice improving it lately, with some success. Gwern points to expert opinion that visual thinking ability might be second only to IQ in terms of intellectual importance. My experience is that when I’m using psychedelics, or deliberately practicing my visualization abilities, I do improve far beyond my perceived abilities. We’re stuck with our IQ, but if it’s possible to improve our visual thinking skills through practice in adulthood, that’s important.

I want to describe my attempts and the outcome.

First Room

I tried this both with a single calculus textbook chapter, and my entire chemistry textbook. The results were similar but different. I’m going to focus on the chemistry palace here.

I close my eyes and allow myself to picture nothing, or whatever random nonsense comes to mind. No attempt to control.

Then I invite the concept of a room into mind. I don’t picture it clearly. There’s a vague sense, though, of imagining a space of some kind. I can vaguely see fleeting shadowy walls. I don’t need to get everything crystal clear, though.

I mentally label the room as the “Ch. 14 room,” or the “rates room.” That means doing lots of things to make the label stick. I speak the words in my head. I picture a banner with them printed on it hanging from the ceiling. Or if I can’t see it clearly, I picture a banner-like thing and just know that it says “rates room.” I picture hourglasses sitting on furniture—the image comes to me much more easily than a banner with text.

I imagine the crucial equations sitting on columnar pedestals. Again, they are easier to picture for some reason. I make sure that I can visually see each piece of the equation. I imagine a label on the pedestal—one says “t1/​2” for the half-life equations; the other says “Integrated rate law,” with an hourglass made out of two intertwined integration signs.

I look up a picture of Svante Arrhenius and picture him in the room. He takes on a life of his own. I can tell he’s proud of his equation, which appears in bold letters at the back of the room, with a sort of curtain around it. He’s the keeper of the room. It takes on a calm atmosphere here. He’s also the doorman. I have to tell him how to calculate the overall reaction order in order to enter. But if he knows that I know how to do it, I don’t have to explain it in as much detail. We have a psychic relationship.

Second Room

Moving backwards to Ch. 13, I once again imagine a new room, the Solutions Room. Standing there, I can still see the entrance to the first room—I can even picture some of the things inside, from a distance. I start populating the room with symbols, objects, equations, and the chemists they’re named after. They are happy to explain things to me as many times as necessary.

Abstract concepts that the book presents in words, still images, or equations get visualized in new ways. Partial pressures become two beakers, one with yellow steam and the other with red steam emerging. They get mixed into a single beaker that now emits a mixture of yellow and red steam, somewhere in between the amounts that the yellow and red beaker emit on their own. François-Marie Raoult is standing by to demonstrate his law to me. There’s a bottle of Coke with Henry’s Law printed on it.

The solubility rules are accessible when I glance at the periodic table on the wall. Rather than seeing a list of rules, I see the individual elements, which take on a life of their own. The alkali metals, ammonium, and nitrate zoom around the room, not interested in talking to anybody, on their own adventure. The halogens are too cool to talk to anybody except silver, mercury, and lead, who are immensely popular. Silver had a falling out with acetate, who’s a communist and not interested in money. Be sensitive! Chromate is a rich chick in an expensive chrome-hubbed car cruising around, looking for a boyfriend. Sulfur is bicurious, so she’ll bond not only with the transition metals but with astatine, arsenic, bismuth, and lead.

I practice traveling back and forth between the first and second rooms. They stay remarkably stable. Unlike recalling flash cards or the textbook, when I’m in my memory palace the ideas come almost unbidden. The elemental relationships I’ve used to conceptualize the solubility rules come bursting out of the periodic table.

Further rooms

I continue this for 6 chapters over the course of several hours. I am shocked and delighted at how easy and pleasant it is both to create the memory palace and to access the memories stored there. Not everything goes in—just the bits that I tend to forget. If I’m not sure about something, the famous chemists who populate the rooms will remind me, literally by talking me through their ideas.

The presence of the chemists is also helpful for keeping me focused. I suspect that my brain is recruiting my social motivation. If the only people in my environment are genius chemists who are delighted to keep me interested in chemistry, then why would I get distracted by the internet?

I find it deeply reassuring to stand in the Intermolecular Forces room and know that just by walking a few rooms over, I can get back to the Rates Room, where all the equations are stored. Perhaps I’ve built a path through the mental mountains? The next day, it’s pretty easy to get back to the memory palace, and everything is as I left it. I just have to close my eyes and wait for a moment to get back in.

Concerns and questions

I also did a memory palace for calculus. I did it day-of because I felt more confident about calculus, it wasn’t a comprehensive exam, and it was open book. I’ll describe it another time. Mostly, it helped me feel more confident that I understood the breadth of the material. I found it much more convenient to refer to the textbook when necessary.

But for tomorrow’s, I’m very glad that I now have a store of chemical facts in my memory palace. The anxiety that had been plaguing me this week has vanished. I’m not certain that it will really help. But I do anticipate continuing to use this technique in the future. I think it helps not only my memory but my synthesis of learning.

For example, our chapter on Lewis Structures also introduces the topic of electronegativity and formal charge. Anyone who’s taken first year gen chem knows they’re related: any negative formal charge should go on the most electronegative atom.

But when I would stare at the electronegativity pages in the textbook, I would focus on the rules offered there: the range of EN difference that characterizes a covalent vs. ionic bond, the periodic trend in EN, and how to calculate net dipole moment. Likewise, in the formal charge section, I would focus on how to calculate the charge.

It took seeing Linus Pauling holding a symbol for electronegativity in one hand, and a symbol for formal charge in the other, to more deeply understand that these are not just two different calculations to do. They’re deeply related ways of modeling how molecules are structured. They go together like yeast and flour.

I also see how much faster and more intuitively I think about both chemistry and calculus when I can visualize them. It’s just no comparison. Trying to remember Raoult’s Law by remembering a verbal description or picturing the equation is just no comparison to looking at those yellow and red steaming beakers. Similarly, it’s so helpful to picture a 3D mountain range and see a tiny little yellow gradient vector surfing up and down it on the steepest slopes.

Advice

I’m a true beginner here, so I don’t want to make any grand claims about how to learn or how useful these techniques are. But I’d give a few pointers so far:

  • If you think you can’t visualize, you might be wrong.

  • Start by just closing your eyes and allowing your brain to produce images without trying to control them. It seems important to have a relaxed, accepting attitude toward my own brain’s way of visualizing.

  • The way to add control is to take a gentle, experimental attitude. Go with what’s easy. Let yourself be surprised by what’s do-able and what’s useful. Is it hard to picture letters on a banner? Try visualizing Isaac Newton and ask him to say the thing you’re trying to remember. Maybe you don’t even need to do that—maybe it’s enough to picture a vague stripe in the sky that you just know is a banner, and you just know has the words “rate room” printed on it.

  • It takes a while to navigate the rooms and get the information you need, so this might need refinement or practice if you’ve got to remember things quickly.

DirectedEvolution19 Jun 2020 2:09 UTC
62 points
16 comments6 min readLW link1 review