 I wonder why mathematicians love blackboards so much. Personally, I chalk it up to a silly tradition, but there's no way that I'm going to get on their bad side by trying to make them change. I can read the writing on the wall. When the Japanese Hageromo Company closed its doors in 2015, a number of the world's most respected mathematicians started hoarding boxes at their widely respected full-touch chalk, buying up whatever they could get their hands on. The articles written about the event share a tone of rye indulgence, implying that the panic induced by the imminent shortage of a particular brand of chalk is just a nerd's being nerd's thing. A foible of academics who are stuck in the story traditions of their field and can't seem to get with the times of smart whiteboards and tablets. The Gizmodo article on the subject implies that the anxious professors are like hipsters chasing a bygone aesthetic, saying, It's not hard to see chalk having old-fashioned appeal, much like final records and mason jars. But for all the light-hearted dismissal, mathematicians did buy up a significant amount of the stuff. There are numerous forum threads where you can see them sharing information about businesses likely to have stock, where to find decent substitute brands, all sorts of very real preparation for the chalk ellipse. It has a semi-serious tone that doesn't feel like Doritos fans tracking down the last few bags of sour cream and onion, chasing some rare luxury for those who can get their hands on it. Some of those threads mention the tongue-in-cheek legend that it's impossible to write a false theorem with Hagodomo Chalk, but I want to consider something less fantastic, but no less fascinating. Maybe the act of writing with the chalk is literally good for doing math. Michael J. Barony, a science historian, noticed an interesting trend. Time after time, mathematics departments would turn down offers from their institutions for fancy high-tech upgrades, like smart cloud-enabled whiteboard projectors, doggedly demanding that their blackboards remain untouched. If you wanted to explain this phenomenon in a way, you could probably say that the mathematicians are just stodgy or old-fashioned by nature. But Barony spent some time observing how people use various media, like whiteboards or pen and paper, and came up with some observations about the act of writing equations on a chalkboard that are unique to the medium. Firstly, it's loud. The quiet scribbling of a pencil or the gentle squeaking of a whiteboard marker doesn't compare to the tack-to-tack-tack of someone banging out a line of proof in chalk. That sound carries an interesting social characteristic. It sort of forbids interruption, at least until the end of the line when the writer has to walk back to the other side of the board. Barony posits that this uninterrupted time is useful, especially for mathematicians who are trying to wind their way carefully down a long path of reasoning and might be derailed by an errant thought or interjection. Whiteboards invite commentary. Blackboards invite you to shut your piehole while I finish this thought. Second, in order to write with chalk, you need a fair amount of space between strokes to keep everything legible, forcing you to stay succinct if you want to fit everything you want to say on a single line. That's kind of what mathematics is, condensing a chain of ideas into a single statement. So it's advantageous for that. Finally, and perhaps most poetically, Barony suggests that the smudges left by small erasures and modifications to the existing equations make the resulting work feel less like an immutable obelisk of perfect truth and more like a creative wrangling of ideas, a hack that shows the hand of its author in which bits get tweaked. Now those are all very squishy feeling notions. If I asked someone to justify using a whiteboard, they could offer all sorts of very straightforward practical sounding arguments. The marker glides effortlessly. Black text on a white background is the most legible combination. There's no chalk dust. You can use a projector without needing a separate screen. Erasing is effortless and clean. But even so, if you were to sneak into a math department and stealthily upgrade all their blackboards with whiteboards, you might well end up with less and worse mathematics than you would if you'd let them keep their chalk. The math-chalk relationship, if it exists the way Barony posits, shares an interesting space with several other traits of human reasoning that can be reliably exploited to vastly improve our cognitive performance in one area or another, but they sound dumb. At the very least, they're difficult to quantify. But also, there's a way we like to conceptualize our thinking. A mental model or story we like to tell about how our minds nominally ought to work. When someone's especially brilliant and exhibits some masterful use of their little gray cells, there are inevitably comparisons to machines or computers. That guy solved the escape room in 20 minutes by himself. He's like a frickin' robot. Researchers have discovered numerous facts that contradict that model. But even if those observations could be incredibly useful for genius-level mental gymnastics, a lot of people tend to ignore them, possibly because they highlight the squishy, often impractical nature of our cognition. For example, there are numerous concrete advantages granted by cloud-based note-taking apps. You can always access your notes anywhere you have access to the internet. You can easily sync them with your calendar software, create reminders, and share them with others. They're searchable, editable, indexable, color-codable, and take up no physical space on your person. With all that functionality and all those advantages, you'd think that paper notebooks, journals, and planners would have simply evaporated. But as much as we might like to imagine that there's no appreciable difference between information conveyed via paper or a screen, there's a substantial body of research that highlights numerous cognitive benefits for physically writing things down versus typing them into your phone or computer. It aids memory and recall. It organizes important information in a way that helps to filter and categorize. It harnesses different kinds of memory, notably spatial memory, in ways that typing just doesn't. Depending on what you're trying to accomplish, dead trees might be the best option. But many people, myself included, have this nagging feeling that with all those benefits of software, we should be able to go paperless. Another example. Numerous private elementary schools have included more and more instruction time in children's schedules, pushing breaks and recesses aside for additional lessons in math, science, whatever. It makes perfect sense. If you're trying to pump as much information as you possibly can into their tiny heads, that you'd want more hours in the day to do that. But kids who spend some of their time playing outside perform better than those who slave away in class by just about any metric you can imagine. Test scores, academic achievement, whatever. The same goes for music classes. There are obvious practical arguments for a correlation between time spent on a subject and performance in that subject. Once your kids to be better at French, they should spend more time in French class. But musicians do better than non-musicians in every possible subject across the board. If you want your kid to be better at French, English, math, science, chemistry, and sports, give them a trumpet. Why? We don't know. We have some ideas. Maybe physical movement builds better mental models about physics. Maybe music encourages synchronization between disparate parts of the brain. We can tell all sorts of stories that explain these phenomena in retrospect, but there's no narrative of the ideal brain as a well-oiled machine that jives with these sorts of findings. When's the last time you took your car into a mechanic for a tune-up and or peggio practice? I think there's a real danger in that sort of misalignment. A possibility of both failing to achieve our full cognitive potential and of judging others by their resemblance to a flawed model. Of course, status quo bias is a thing too. Many people refuse to invest the time or mental energy necessary to learn new systems, work in unfamiliar environments, or develop new skills, because they're uncomfortable. That's how you get AOL email addresses in 2020. But even so, maybe we're doing mathematicians of the service when we tease them about their very specific chalk preferences, suggesting that it's just a quaint affinity for anachronisms or that they just can't get used to other media. Maybe when Hagaromo Chak became scarce, it really was a blow to mathematics as a discipline, robbing us of a tool that leveraged some useful features of the human mind. Despite our narratives about how minds are supposed to work, it's important to pay close attention to how they actually work, including all the little foibles and idiosyncrasies that we tend to roll our eyes at or feel embarrassed about. Instead of trying to think like a super intelligent machine, maybe try thinking like a smart human who exploits useful psychological tools no matter how stupid they sound. Can you think of some useful tricks that work on human thought but don't square with our usual conception of it? Please leave a comment below and let me know what you think. Thank you very much for watching. Don't forget to blah, blah, subscribe, blah, share, try out the Discord, and don't stop thunking.