I just finished Robert Greene's notorious 2 Areas/3 Notes/3 Sciences/0 Mathematics/AM3D Axioms, postulates/48 Laws of Power/48 Laws of Power.

The book is exactly what it sounds like: a guide to acquiring power in 48 easy steps. It's a self-help-book-meets-historical-medley that makes for an engaging albeit cynical read— everyone's out for themselves, and it's dominate or be dominated.

No surprises, the book has become a cult classic among hip-hop artists, and entrepreneurs, but also prison inmates and domestic terrorists. Now, these less-than-reputable associations may lend the book an exciting bad-boy appeal (Law 6), but, at the end of the day, popularity among criminals also hints at some kind of defect (Law 10).

Don't get me wrong, I loved the book (if only for the historical examples), but Greene's theatrically nihilistic worldview gets a few key things wrong. I thought I'd point those out, and offer an antidote in what I'll call, 1 Projects/Writing/02 Series/The 48 Laws of Cooperation/The 48 Laws of Cooperation

1. Power is a weak end

First, power is not an end but a means. You can tell your audience to always keep "the end" in sight (Law 47), but if you don't teach your audience which goals to aim for, power becomes its own end. You end up proselytizing a cult of power that leaves us all weaker.

Instead, power needs a purpose that goes deeper than saturating one's need to believe (Law 27). Power is a tool to work towards your own well-being (and, if you're feeling generous, the well-being of those around you). Only the most thoroughly psychopathic can extract well-being directly from power. For the rest of us, our most reliable and profound sources of well-being often require us to willingly give up power¹ : to do things for others, to open up and be vulnerable, and to efface the ego.

If you're not using your power to help the people out of power—to make the game more immune against the power-hungry—you're a sad, unenviable douchebag.

2. Power is an incomplete lens

Second, power is not everything in human interactions— not nearly.

With power, interactions become a zero-sum affair: dominate or be dominated. The vulnerability is that this lens is self-affirming. If you seek power, you surround yourself with power-hungry competitors who confirm your cynical suspicions and, in turn, their own.

The most interesting (and complex) interactions have less to do with power, and they are not nearly so minimax-able. These situations are closer to Prisoner's Dilemma's: You and your "opponent" are equals. Your interests are almost aligned but not quite. Cooperation is in sight but, unless you put in the extra effort, no guarantee.

The power-hungry cynic will choose defection as soon as it becomes strategically favorable (Law 13) because they cannot imagine their opponent acting any other way (or if they can, they disparage the opponent as a "sucker" to be taken advantage of; Law 33). In the long run, such a strategy will leave your community fragile, its members wary and distrusting, and you alone in all existence.

Just try it. Try the 48 laws out on your kids. You will be estranged before they leave the house. Try it out on potential partners. Yours will be a string of unhappy flings. Try it out at work. "Friend" will be an abstract dictionary definition without any foothold in your world. You may be the greatest actor and deceiver (Law 3) of all time, but you can't stay (or want to be) impenetrable to those closest to you. And eliminating all your emotional intimates is a self-evidently imbecilic move (Law 18).

3. History remembers the lucky

Third, Greene gets to cherry-pick the greatest power-seekers in history. But the stories of most of those who tried and failed don't get written. If you try and follow the greats, odds are you will end up with the rejects. If you view the world as you-against-everyone-else (which is the cynical result of all the power worshiping), the numbers will be on your opponents' side. You will lose (and maybe end up in prison worshiping the book whose mentality got you in this mess).

Better to cooperate than to defect. Your best chance at both security and well-being is to side with a community that looks out for you. When you willingly sacrifice your individual power for the good of those around you and they reciprocate, you will be infinitely more powerful than you could ever have been in a group of self-interested megalomaniacs.

Listen to Seneca: "If a thing is in your interest it is also in my own interest. Otherwise, if any matter that affects you is no concern of mine, I am not a friend. Friendship creates a community of interest between us in everything. We have neither successes nor setbacks as individuals; our lives have a common end."

Greene gets a little closer to "cooperation" with his other book, The 33 Strategies of War. But it remains the perspective of the general, the man above and beyond his fellow soldiers. It can be lonely up there.

Like power, cooperation is no guarantee. It takes work to realize; you have to follow rules and principles— say about 48 of them.

In the coming weeks, I'll be releasing my antidote to Greene, 1 Projects/Writing/02 Series/The 48 Laws of Cooperation/The 48 Laws of Cooperation, in serial form. Sign up to stay tuned.

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P.S. In Greene's defense, his book is not as unrelentingly cynical as I paint it to be. Obviously, cooperation has a value to the power-hungry. Call me a romantic, but I just don't agree that power stands above cooperation. In fact, I think this mentality is one of the deadly diseases of our time and place.

Forgive me where I exaggerate. Then again, Law 6 and Law 42 tell me a good way to gain attention is to attack a well-established person in power. Today, that person just so happens to be you, Mr. Greene.

P.P.S. Greene accuses those who claim they are outside the game of power to be lying (or to be ignorant). That those who make an appeal to equity want to parcel out the resources myself. No, my appeal to equity does not mean that I want to be the one to redistribute the power. Despite all of its failures, democracy remains our best solution to that. But yes, I'm sure that being seen as generous and liberal (in the classic sense), i.e., signaling my virtue, is one of my motivations for writing about cooperation. Again no, my demonstration of honesty in revealing this motivation is not designed to gain more brownie points. Then again, this whole meta-self-referential analysis probably is.

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Footnotes

Footnotes

1. Actually making sacrifices — not just making the appearance (Law 22). ↩

Day of Rest

Many cultures observe a "day of rest."

Though often packaged in mawkish religiosity, these days of rest have something to teach even the most fundamentalist secularists among us.

But we already know that. For the body, we take rests days to prevent injury. For the mind, many productivity-zealots dabble in dopamine fasts and daily meditations because creativity and self-awareness require a balance of focused thinking and diffusive thinking[^1]. We can't get to diffusive thinking without undirected time for reflection.

Still, at least for me, the idea of dedicating one day a week to doing nothing sounds a little extreme. As far as I can tell, I don't have a spiritual void to fill with the a weekly church service, and my daily moments of pause—in meditation, meals, and walks—are currently enough to prevent mental collapse. Why sacrifice time that I could be doing something?

Day of Maintenance

Instead of a day of rest, then, I propose a day of maintenance. If you're anything like me (and, I wager, most humans), you're liable to suffer a severe case of novelty bias—constantly starting new projects without finishing what you've already started. ¹

On a day of maintenance, you'd curtail content creation (be it in writing, programming, researching, painting, composing, etc.). Instead, you'd maintain what you've already begun. E.g.: cleaning up your Zettelkasten, trimming your GitHub repos, maybe writing the documentation and tests you've been putting off, organizing your references, managing your GTD and email inboxes, and conducting a weekly review.

Moreover, you can easily combine it with your more mundane household chores: vacuuming and tidying, washing your clothes, or doing a groceries haul.

Especially when a pandemic and lock-down threaten to turn your every day into a copy of every other, a day of maintenance, rest, or "the lord" might be just the thing that restores your control over time. And maybe if we all spent just a little more time on maintenance, there'd be just a little less crap out there: less garbage code, out-of-date libraries, repetitive apps, and disappointing platitudes. So get maintaining.

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Footnotes

[1]: Aka system one versus system two thinking or the default mode network versus task-positive network.

Footnotes

1. Right after I finished my first draft of this piece, I found Cody McLain's The Importance Of A Maintenance Day And Why You Need One. Like always and everywhere, it's impossible to be original. Even in presentation. Oh well. ↩

Nobel laureate in physics and father of the "atomic age," Enrico Fermi was also a gifted guesser. Rather than tackle complex problems head-on, Fermi would break them apart into tiny, simpler chunks, then compose these chunks to get back at the whole. It's a strategy we have much to learn from.

This process is perhaps best reflected in the paradox that bears Fermi's name. At a lunch in 1950, he raised the following question to his audience: where is everybody? (The extraterrestrials, that is.) Fermi followed with a characteristic calculation that anticipated the Drake equation:

Even with moderate guesses for the later parameters, the sheer number of stars led Fermi to conclude that "we ought to have been visited long ago and many times over" (Jones 1985). Hence the paradox.

Fermi understood that the more guesses he fit into his break-down, the more reliable his final answer would be. That's because as long as your errors are unbiased, they will tend to balance each other out. Guess a little too much over here, a little too much over there, and your answer will come out in the reasonable middle.¹ ^dc6a5a

Thus Fermi was able to estimate the energy of a nuclear blast from the movement of a floating piece of paper and the number of piano tuners in Chicago without turning to yellow pages. He wouldn't get the exact figure, but he could expect a reasonable order-of-magnitude (power of ten) estimate.

Like the paradox, these kinds of back-of-the-envelope questions are now known as Fermi questions. It's worth learning how to solve Fermi questions. First, because you'll hone your bullshit detector for the statistics garbage floating around cyberspace and dinner tables. Next, because practice with Fermi questions weaponizes your internal store of facts (see 1 Projects/Writing/02 Series/Memorizing/Memorizing numbers and 1 Projects/Writing/02 Series/Memorizing/Memorizing units). You'll be able to construct quantitative arguments on the fly that grant your reasoning a significant credibility boost.

Now I hate to give a cop-out answer, but the best way to learn how to solve Fermi questions is to solve Fermi questions. Keep an eye out and a notepad handy. If you're desperate for more structured practice, you can check out the book, Guesstimation, by Lawrence Weinstein and John A. Adam, which has dozens of excellent examples. But, really, everyday debates should present enough opportunities for practice.

That said, one thing you can do which really will help is to memorize reference figures and statistics. So that you can collapse a few of your guesses onto certainties to make your conclusions all the more likely. Check out the Anki deck I made for learning units for a previous article.

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Footnotes

Footnotes

1. For this to work, your guesses should have similar, not-too-large error margins. This is why we can't really judge Fermi's claim of omnipresent aliens. Who knows what the chance is of a planet bearing life? Or of a species developing intelligence? Escaping the dark ages? Circumventing anti-vax-climate-change-denying-nuclear-war-hawks? ↩

This is the second part in a four-part series on memorizing statistics.

1. 1 Projects/Writing/02 Series/Memorizing/Memorizing numbers (start here)
2. 1 Projects/Writing/02 Series/Memorizing/Memorizing units (you are here)
3. 1 Projects/Writing/02 Series/Memorizing/Memorizing sequences (to be written)
4. Memorizing sources (to be written)

Previously, we covered memorizing numbers such as dates, rates, and percentages with the Major system and Anki. But numbers are only a small part of the equation: with real-world statistics, the units matter as much as the digits themselves—especially when we're interested in actually using statistics.

❌ Don't Memorize the Units

Dimensions and units

First, we have to make a distinction between dimensions and units. Dimensions are the underlying physical variables (e.g. length, time, energy, power). Units are reference scales to measure and compare the underlying variables (e.g. meters for length, seconds for time, joules for energy, watts for power).

Whenever you can, avoid explicitly memorizing the dimensions. Instead, derive these by physical intuition. After all, the first rule of memorizing is to understand first. If you really understand what a statistic means, the dimensions should explain themselves.

Let's return to the example of climate-crisis statistics. If you're talking about global emissions, you know the dimensions are of mass: emissions are material, and matter is measured in mass¹. But if you're talking about the energy consumption of a country, you'll need to use dimensions of energy. And if you're judging the production capacity of a new power station, you're interested in power (energy per time).

So too, we'd like to avoid explicitly memorizing units when possible. But this is harder to do because for every dimension there are a dozen alternative units: kilometers and miles, short tons, metric tons, and long tons, Kelvin, Celsius, Rankine, and Fahrenheit, etc.

Our saving grace is the international system (SI from the French système international) of units. If we know that a statistic obeys the SI conventions, there's only one option for every unit. Distance has to be measured in meters, mass in kilograms, temperature in Kelvin. Then, all we have to explicitly memorize is the particular unit prefix (e.g. kilo-, mega-, giga-).

So the easiest thing to do is to convert every statistic you'd like to memorize to SI units before storing them in your spaced repetition system. You'll have to memorize what the SI units are, but you only have to memorize this once for easier memorizing always. It'll also help to know common conversion factors so you can transform these statistics back to whatever other units you later desire.

🌐 SI units

So I've thrown together an Anki deck to help you learn the most common SI units. You can find it here. As always, before you jump in, make sure you have some overview of what the units actually mean (e.g., read their wikis).

Base Units

There are 6 "base units." These are the units whose values are set by actual physical measurements. The rest of the units are "derived" from these base units, 22 of which have special names (typically after notable physicists and chemists). The rest have self-explanatory names (e.g., meter per second and joule per Kelvin).

Symbol	Name	Dimension
$\text{s}$	second	time
$\text{m}$	meter	length
$\text{kg}$	kilogram	mass
$\text{A}$	ampere	electric current
$\text{K}$	kelvin	thermodynamic temperature
$\text{mol}$	mole	amount of a substance
$\text{cd}$	candela	luminous intensity

Derived Units

Symbol	Name	Dimension	Equivalents
$\text{Hz}$	hertz	frequency	$1/\text{s}$
$\text{N}$	newton	force, weight	$\text{kg}\cdot\text{m}/\text{s}^2$
$\text{Pa}$	pascal	pressure, stress	$\text{N}/\text{m}^2$
$\text{J}$	joule	energy, work, heat	$\text{N}\cdot\text{m}$, $\text{C}\cdot\text{V}$
$\text{W}$	watt	power	$\text{J}/\text{s}$
$\text{C}$	coulomb	electric charge	$\text{s}\cdot\text{A}$, $F\cdot V$
$\text{V}$	volt	voltage, electric potential difference	$c$

and more. . . .

Unit Prefixes

I've also included a subdeck to help you memorize the meanings of the standard prefixes.

Symbol	Name	Value
y	yocto	$10^{-24}$
z	zepto	$10^{-21}$
a	atto	$10^{-18}$
f	femto	$10^{-15}$
p	pico	$10^{-12}$
n	nano	$10^{-9}$
μ	micro	$10^{-6}$
m	milli	$10^{-3}$
c	centi	$10^{-2}$
d	deci	$10^{-1}$
		$10^{0}$
da	deca	$10^{1}$
h	hecto	$10^{2}$
k	kilo	$10^{3}$
M	mega	$10^{6}$
G	giga	$10^{9}$
T	tera	$10^{12}$
P	peta	$10^{15}$
E	exa	$10^{18}$
Z	zetta	$10^{21}$
Y	yotta	$10^{24}$

💱 Conversions

Of course, you'll sometimes have to convert to non-SI units. For car speeds kilometers per hour can be more useful than meters per second. And a stubborn fraction of the world continues to cling to the imperial system. So I've added in a subdeck of common conversion factors.

🏔 Reference Objects

Finally, I've added a subdeck that includes reference objects to help you build intuition for different scales of magnitude (e.g. the land-area of Manhattan versus New York State vs Earth, etc.). These reference values may seem arbitrary, but they'll help make the different units and unit-prefix pairings way more tangible.

♟ Memory Pegs

Still, sometimes we'll want to explicitly associate a number to units. Especially when we want to memorize a statistic in its original non-SI formulation. Maybe because the convention in a particular discipline is non-SI. Astronomers prefer light-years and parsecs over petameters for good reason: they former are more practical.

For example, suppose I were trying to memorize that the total electricity end-use of the US in 2019 was 4.19 terawatt-hours (EIA 2020).

In the last chapter, we saw how we might memorize "4.19." 4, 1, and 9 become the consonants r, d/t, and p/b. Then, we compose these into, for example, "red top" (eliding the d-t), and we imagine a spinning red top. Easy.

But it won't be enough just to memorize 4.19 or even 4.19 + "tera" so long as there's an ambiguity between tera-joules and tera-watt-hours. We need an explicit link between the quantity "4.19", the prefix "tera-," and the unit "watt-hours."

The difficulty is that every one of these items is abstract, and our brains have a hard time memorizing abstract objects. That's where the power lies in a trick like the Major system: we turn the abstract and difficult-to-remember into a concrete and much-easier-to-remember "red top."

Memory pegs are similar. But instead of inventing a new object every time we encounter a new item, we choose the associations ahead of time (usually by rhyme or word similarity). It's useful when the set of objects to memorize is bounded (such as our system of units).

For example, "joule" sounds like "jewel," so my memory peg for "joule" could be some grossly large pink jewel. Meanwhile, "watt" makes me think of "Watson," so my peg could be the duo Sherlock Holmes and Dr. Watson. "Tera" makes me think of "terra," the planet we live on. Finally, "hour" becomes "whore" (or some more PG alternative if it's parents reading this).

Putting it all together, 4.19 Terawatt-hours becomes Dr. Watson and a whore balancing on a globe balancing on a spinning red top (raunchiness makes for great memory).

To help you along, I've added a field for memory pegs in the Anki decks I provided above. I filled in my own choice of memory pegs both for the units and the unit prefixes. These might work for you or not, so I recommend you first go through the deck and swap out any pegs you don't like (remember to always personalize your notes). When intuition is not enough, it's memory pegs that will help you recall the units and prefixes for any given statistic.

👀 Conclusion

With the right combination of physical intuition and memory pegs, you have everything you need to memorize numbers and units. Combining the first two chapters, we have a strategy that looks something like this:

1. 🔢 Use the Major system to convert the number into a concrete object. (4.19 -> "red top")
2. 📏 Use physical intuition to identify the relevant dimensions. ("electricity consumption" -> "power")
3. 🗃 Retrieve the possible units corresponding to these dimensions from memory. If there are multiple options (e.g. joules and kilowatt-hours), use a memory peg to distinguish between the options. If there aren't, you can leave the units implicit. (watt-hours -> "Watson + whore")
4. ♟ Memorize the unit prefix with a memory peg. (tera- -> "globe (terra)")
5. 🔗 Visualize an association between the number-derived object and the unit-derived memory peg(s). ("Dr. Watson and a whore balancing on a globe balancing on a spinning red top ")

💡 Bonus: Developing Physical Intuition

But how to develop the physical intuition you need to make memorizing units automatic? It's a chicken-and-egg problem: you don't develop the intuition until you regularly use the units, but you can't use the units until you have intuition for using them.

So put a stop to the decision paralysis and start by learning the units. In a future post, we'll tackle how to put your newly-memorized statistics to good use in the kinds of back-of-the-envelope calculations that can make or break debate.

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Footnotes

Footnotes

1. Okay, so actually this gets more complicated. First, you could measure emissions in moles (number of particles), but mass is more practical. Also, you have to qualify your units of emissions by the type of greenhouse gas (GHG) (e.g. CO2, CH4, N20) because every GHG has a different global warming potential (i.e. how much a gram of material increases warming). So if you want to compare them against one another, you have to convert the gases to a baseline (usually, gigatons of CO2-equivalents). But then every one of these compounds has a different half-life. So you have to specify the time-period over which you're comparing global warming potentials. And you end up with something like gigatons CO2-equivalents-100-years (gTC02e100). Complicated. ↩

For most of us, numbers are difficult to memorize. Even with a spaced repetition system like Anki.

Biological determinism 2 Areas/Principles/Laws/Weber-Fechner law#Corollary

This difficulty may be a relic of our evolutionary history: relative number mattered more than absolute number—mass mattered more than count. Fortunately, humans have a way of subverting biological fatalism. Over the past millennia, we've developed mnemonic tricks that make it easier to memorize all kinds of facts—numbers and statistics included.

2 Areas/Principles/Laws/Why memorize (Pt. 1)

Because there is a real value to memorizing numbers, statistics, and facts more generally. In debate, quantities ground the conversation in reality; they prevent you and your opponent from floating off into hypotheticals. With the right restraint, a large factual memory can improve your impartiality: you discuss facts rather than beliefs. And the very presence of such a memory can grant you credibility. Memory matters.

In this article, I'm going to break down how to memorize numbers using the Major system. In follow-ups, we'll cover how to memorize units, orders, and sources. Together, you'll have all you need to memorize general statistics.

In particular, I'm interested in integrating these techniques with my spaced repetition workflow. So that memorizing statistics is no one-off thing but part of continual practice.

🎳 Interference

In practice, the more relevant obstacle to memorizing numbers is not evolutionary history but interference: numbers compete with one other for mental bandwidth. And numbers "interfere" more intensely than do words. You probably have a harder time separating 43%/34% and 1367/1376 than cat/mat and dog/god. We don't have the same semantic horse-power pulling apart numbers as we do words.

It gets even harder to memorize when you're dealing with statistics, where you also care to memorize units and sources. Good luck keeping apart acronyms like the UNHCR, UNHRC, and UNCHR (that's the United Nations high commissioner for refugees, human rights council, and commission on human rights, respectively).

GHG emissions breakdown

GHG

🌎 An Example: the Climate Crisis

Because we're interested in memorizing for the real world, let's use a real-world example to memorize.

I'd like to contribute in the fight against climate crisis. To begin, I'd like a better understanding of where exactly our emissions come from. So I am going to commit a whole bunch of climate statistics to memory.

According to the World Resources Institute Climate Watch report (2020) (henceforth, WRI 2020), we produced 49.4 billion tons of CO2-equivalents in 2016 with an uncertainty of about 10%.

Significant figures and error

1 Projects/Writing/02 Series/General/Fermi questions To share an estimate without a measure of its uncertainty or spread is statistical sacrilege. But in less formal settings, we can usually get away with it. That's because the important point is usually the order of magnitude—to know we produced about 50 GtCO2e but not 5 or 500. (If your statistic has error bars greater than an order of magnitude, look for a new statistic.)

The best way to emphasize the relevant order of magnitude is to reduce the number of digits you report. With an uncertainty of 10%, saying "50GtCO2e" is most honest representation.

But sometimes, it can can be advantageous to over-report the digits: "49.38" carries more rhetorical emphasis than "about 50." With the right timing, pulling out all the digits can overwhelm the opponent. But don't do this too often because it is misleading and can be outright pretentious. It's also dangerous because if your opponent requests the error bars, you will end up looking the fool. So judge wisely.

🔢 1-2 Digits Major system

The WRI divides global emissions into 4 top-level sectors (in order of decreasing magnitude):

1. ⚡️ Energy (electricity, heat, and transport): 73.2%
2. 🚜 Agriculture, forestry, and other land-use (AFOLU): 18.4%
3. 🏭 Industry (cement, ammonia, plastics, and other chemicals): 5.2%
4. 🗑 Waste: 3.2%

The principle behind the major system is to associate a unique consonant sound or related set of consonant sounds with each digit. Then, we can read the digits like an abjad by converting numbers into words and words back into numbers.

A Possible Mapping

Number	Consonant
0	s, z, soft c
1	t, d
2	n, ng
3	m
4	r
5	l
6	sh, ch, j
7	k, hard c, hard g, hard ch, q, qu
8	f, v, th, dh
9	p, b

For our example:

1. ⚡️ Energy: 73.2% -> KMN
2. 🚜 AFOLU: 18.4% -> TFR
3. 🏭 Industry: 5.2% -> LN
4. 🗑 Waste: 3.2% -> MN

With a little practice, we get better at turning these into words (the more concrete, the better):

• KMN -> Camion, Come on, Caiman
• TFR -> Tover (Dutch for "magic"), To throw, taffrail (dropping the l)
• LN -> Lion, lan, lawn, lane
• MN -> Money, moan, man

Now, all we have to do is memorize a pairing between two much less abstract objects. For energy and "caiman", I might imagine a radioactively-glowing alligatorid puffing black smoke from its orifices. For AFOLU and "tover" (magic), I visualize a magician converting a large John Deere Tractor into a puff of smoke (actions are more memorable). For industry and "lion," it's a lion trapped in cement, struggling to free itself while it's buried alive in fertilizer (emotional imagery works even better). For waste and money, the Joker burns his large pile of cash.

And it's these pairings that I'll put in my Anki (and if I have the time I'll add or even draw a picture for extra stickiness).

With a little practice, you'll soon get better and faster at this entire process. At the next layer of resolution, we go through the same process

1. 🏭 Energy use in industry: 24.2% -> NRN -> Neuron
2. 🚗 Transport: 16.2% -> DCHN -> Dejeune (from Fr. for "breakfast")
3. 🏘 Energy use in buildings: 17.5% -> TKL -> Tackle
4. 🎉 Unallocated fuel combustion: 7.8% -> KF -> Keef
5. 🌋 Fugitive emissions from energy production: 5.8% -> LF -> Love
6. 🚜 🎣 Energy in Agriculture & Fishing: 1.7% -> DK -> Dock

I'll leave the final images to you.

Special symbols

There's more to numbers than the numerals. There are decimals, percentage signs, ranges, and powers. Without these, how would you know whether "lion" is 52 or 5.2 and "money" 32 or 3.2. Usually, context suffices. Take decimals: if you understand the physical origins of emissions, you'll know that energy production operates at a much larger scale than emissions from cement and ammonia production or from anaerobic respiration in oxygen-poor landfills. But when you need more help, you can use specific memory pegs for these special characters. E.g.: a decimal might become a laser pointer. To make numbers even more memorable, imagine a super-powerful laser slicing the remaining objects in half.

This is a starting point for memorizing 2 or more digits. But it may be slightly overkill for memorizing single digits (as with order of a sequence of elements). And it doesn't help us memorize the units (which are subject to the same problems of interference as digits). Nor sources (with a flurry of names and organizational initialisms). So stay tuned, for the follow-ups.