Reading the Comics, February 9, 2019: Garfield Outwits Me Edition


Comic Strip Master Command decreed that this should be a slow week. The greatest bit of mathematical meat came at the start, with a Garfield that included a throwaway mathematical puzzle. It didn’t turn out the way I figured when I read the strip but didn’t actually try the puzzle.

Jim Davis’s Garfield for the 3rd is a mathematics cameo. Working out a problem is one more petty obstacle in Jon’s day. Working out a square root by hand is a pretty good tedious little problem to do. You can make an estimate of this that would be not too bad. 324 is between 100 and 400. This is worth observing because the square root of 100 is 10, and the square root of 400 is 20. The square of 16 is 256, which is easy for me to remember because this turns up in computer stuff a lot. But anyway, numbers from 300 to 400 have square roots that are pretty close to but a little less than 20. So expect a number between 17 and 20.

Jon swipes his card at a supermarket checkout. The reader asks: 'Would you like to donate a dollar to charity today?' (Boop.) 'Enter PIN.' (boop boop boop boop.) 'Your total is $3.24. Is this correct?' (Boop.) 'What is the square root of 324? Please show your work.' Jon: 'ALL I WANT IS A BAG OF CHEESE DOODLES!' Garfield: 'DON'T WE ALL?!!'
Jim Davis’s Garfield for the 3rd of February, 2019. Other essays featuring Garfield would be at this link. But somehow this is the first time I’ve had something to write about based in Garfield. Huh.

But after that? … Well, it depends whether 324 is a perfect square. If it is a perfect square, then it has to be the square of a two-digit number. The first digit has to be 1. And the last digit has to be an 8, because the square of the last digit is 4. But that’s if 324 is a perfect square, which it almost certainly is … wait, what? … Uh .. huh. Well, that foils where I was going with this, which was to look at a couple ways to do square roots.

One is to start looking at factors. If a number is equal to the product of two numbers, then its square root is the product of the square roots of those numbers. So dividing your suspect number 324 by, say, 4 is a great idea. The square root of 324 would be 2 times the square root of whatever 324 ÷ 4 is. Turns out that’s 81, and the square root of 81 is 9 and there we go, 18 by a completely different route.

So that works well too. If it had turned out the square root was something like 2\sqrt{82} then we get into tricky stuff. One response is to leave the answer like that: 2\sqrt{82} is exactly the square root of 328. But I can understand someone who feels like they could use a numerical approximation, so that they know whether this is bigger than 19 or not. There are a bunch of ways to numerically approximate square roots. Last year I worked out a way myself, one that needs only a table of trigonometric functions to work out. Tables of logarithms are also usable. And there are many methods, often using iterative techniques, in which you make ever-better approximations until you have one as good as your situation demands.

Anyway, I’m startled that the cheese doodles price turned out to be a perfect square (in cents). Of course, the comic strip can be written to have any price filled in there. The joke doesn’t depend on whether it’s easy or hard to take the square root of 324. But that does mean it was written so that the problem was surprisingly doable and I’m amused by that.

T-Rex: 'Say the average person can expect to live for 81 years. That's a little over 2.5 billion seconds. 2.5 billion is not that much! I thought I'd compare the seconds in a life to the molecules in a glass of water, but even a gram of water has over ten sextillion molecules in it. Even if I measure my life in NANOSECONDS I'm still not on par with a gram of boring ol' WATER.' Dromiceiomimus: 'Molecules are super tiny, T-Rex! You should measure yourself in bigger units.' T-Rex: 'like ... cubic millimeters?' Utahraptor: 'That'd give you 2500 litres, that's a lot!' T-Rex: 'Dude, that's just a GIANT BATHTUB! I want to visualize my lifespan as something impressive!' Utahraptor: 'OK. 2.5 billion kilometers is enough to make a one-way trip to Saturn and get most of the way back before dying, OR to travel part of the way to Uranus, but again, dying well before you arrive.' LATER: T-Rex: 'Dear audio diary! Today I learned why we measure lifetimes in years and not in 'failed trips to Uranus where only corpses show up at the end'. It's, um, for the reasons you'd expect, basically.'
Ryan North’s Dinosaur Comics for the 4th of February, 2019. Some of the many essays inspired by Dinosaur Comics appear at this link.

Ryan North’s Dinosaur Comics for the 4th goes in some odd directions. But it’s built on the wonder of big numbers. We don’t have much of a sense for how big truly large numbers. We can approach pieces of that, such as by noticing that a billion seconds is a bit more than thirty years. But there are a lot of truly staggeringly large numbers out there. Our basic units for things like distance and mass and quantity are designed for everyday, tabletop measurements. The numbers don’t get outrageously large. Had they threatened to, we’d have set the length of a meter to be something different. We need to look at the cosmos or at the quantum to see things that need numbers like a sextillion. Or we need to look at combinations and permutations of things, but that’s extremely hard to do.

Tube Sock: a white cylinder with two blue stripes near the top. Inner Tube Sock: a white torus with two blue stripes around the narrow radius.
Tom Horacek’s Foolish Mortals for the 4th of February, 2019. This is a new tag. When I am next moved to write about Foolish Mortals the results should be this link. This might be a while. I can find some examples of writing about this strip in 2014, before I tagged the comic strips by name, but not since then.

Tom Horacek’s Foolish Mortals for the 4th is a marginal inclusion for this week’s strips, but it’s a low-volume week. The intended joke is just showing off a “tube sock” and an “inner tube sock”. But it happens to depict these as a cylinder and a torus and those are some fun shapes to play with. Particularly, consider this: it’s easy to go from a flat surface to a cylinder. You know this because you can roll a piece of paper up and get a good tube. And it’s not hard to imagine going from a cylinder to a torus. You need the cylinder to have a good bit of give, but it’s easy to imagine stretching it around and taping one end to the other. But now you’ve got a shape that is very different from a sheet of paper. The four-color map theorem, for example, no longer holds. You can divide the surface of the torus so it needs at least seven colors.

Wiley's Dictionary, as read by Peter: 'Logarithm. A downed tree with dance moves.'
Mastroianni and Hart’s B.C. for the 5th of February, 2019. Essays describing some aspect of B.C., whether the current run or the vintage 1960s reruns, appear at this link.

Mastroianni and Hart’s B.C. for the 5th is a bit of wordplay. As I said, this was a low-volume week around here. The word “logarithm” derives, I’m told, from the modern-Latin ‘logarithmus’. John Napier, who advanced most of the idea of logarithms, coined the term. It derives from ‘logos’, here meaning ‘ratio’, and ‘re-arithmos’, meaning ‘counting number’. The connection between ratios and logarithms might not seem obvious. But suppose you have a couple of numbers, and we’ll reach deep into the set of possible names and call them a, b, and c. Suppose a ÷ b equals b ÷ c. Then the difference between the logarithm of a and the logarithm of b is the same as the difference between the logarithm of b and the logarithm of c. This lets us change calculations on numbers to calculations on the ratios between numbers and this turns out to often be easier work. Once you’ve found the logarithms. That can be tricky, but there are always ways to do it.

Mother: 'Maggot, help Otis with his math homework. Explain fractions to him.' Maggot, to Otis: 'Well, it's like when you drop a beer bottle and it breaks into a lot of pieces.'
Bill Rechin’s Crock rerun for the 8th of February, 2019. I have no information about when this strip previously appeared. Essays based on things mentioned in Crock appear at this link. Somehow this isn’t the first time I’ve tagged this comic.

Bill Rechin’s Crock for the 8th is not quite a bit of wordplay. But it mentions fractions, which seem to reliably confuse people. Otis’s father is helpless to present a concrete, specific example of what fractions mean. I’d probably go with change, or with slices of pizza or cake. Something common enough in a child’s life.

And I grant there have been several comic strips here of marginal mathematics value. There was still one of such marginal value. Mark Parisi’s Off The Mark for the 7th has anthropomorphized numerals, in service of a temperature joke.


These are all the mathematically-themed comic strips for the past week. Next Sunday, I hope, I’ll have more. Meanwhile please come around here this week to see what, if anything, I think to write about.

Reading the Comics, December 28, 2018: More Christmas Break Edition


I apologize for running quite so late. Comic Strip Master Command tried to make it easy for me, by issuing few comic strips that had any mathematical content to speak of. I was just busier than all that, and even now, I can’t say quite how. Well, living, I suppose. But I’ve done plenty of things now and can settle back to the usual, if anyone knows just what that was.

Also I am drawing down on the number of cancelled, in-eternal-reruns comic strips on my daily feed. So that should reduce the number of times I feature a comic strip and realize I’ve described it four times already and haven’t got anything new to say. It’s hard for me, since most of these comics have some charms, or at least pleasant weirdness. But clearly just making a note to myself that I’ve said everything there is to say about Randolph Itch, 2 am, isn’t enough. I’m sorry, Randolph.

Bill Holbrook’s On The Fastrack for the 28th is an example of the cartoonist’s habit of drawing metaphors literally. Dethany does ask the auditor Fi about “accepting his numbers”. In this context the numbers aren’t intersting as numbers. They’re interesting as representations for a narrative. If the numbers are consistent with a believable story? If it’s more believable that they represent a truth than that they’re a hoax? We call that “accepting the numbers”, but what we’re accepting is the story they’re given as evidence for.

Man giving a presentation; it's a string of digits on the whiteboard. A giant thumb swipes across it, and the numbers all fall off, leaving the man disheartened. Last panel, the man walks out, dejected. Dethany: 'Did you accept his numbers?' Fi: 'I swiped left.'
Bill Holbrook’s On The Fastrack for the 28th of December, 2018. Essays discussing topics raised by On The Fastrack should all appear at this link.

Auditing, and any critical thinking about numbers, involves some subtle uses of Bayesian probability. We’re working out the probability that this story is something we should believe. Each piece of evidence makes us think this probability is greater or lesser. With experience and skill one learns of patterns which suggest the story is false. Benford’s Law, for example, is often useful. Honestly-taken samples show tendencies, for example, in what leading digits appear. A discrepancy between what’s expected and what appears, if it can’t be explained, can be a sign of forgery.

B.C.: 'How many grains of sand are on this beach?' Peter: 'Five hundred and sixty gillion.' B.C.: 'You're a genius, Peter.'
Johnny Hart’s Back To BC rerun for the 27th of December, 2018. From the dating it apparently originally ran the 1st of July, 1961. Essays mentioning B.C., both 1961 vintage and 2019 current, should be at this link.

Johnny Hart’s Back To BC rerun for the 27th is built on estimating the grains of sand on a beach. This is, as fits the setting, a very old query. Archimedes wrote The Sand Reckoner which estimated how many grains of sand could fit in the universe. Estimating the number of grains of sand on a beach, or in a universe, is a fun mathematical problem. Perhaps not a practical one, not directly. The answer is after all “lots”, and there is no way to verify the number.

But it can still be indirectly practical. To work with enormous but finite numbers of things is hard. We do well working with small numbers like ‘six’ and ‘fourteen’ and some of us are even good at around ‘thirty’. We don’t have a good intuition for how a number like 480,000,000,000,000,000 should work. And that’s important; if we try adding six and fourteen and get thirty, we realize there’s something not quite right before we’ve done too much more work. With enormous numbers we can go on not noticing the mistake’s there. We need to find ways to understand these inconvenient numbers using the skills and intuitions we already have. Aristotle had to develop new terminology for numbers to get the Ancient Greek numerals system to handle the problem coherently. Peter’s invention of a gillion is — I’ll go ahead and say — a sly reenactment of that.

Neil: 'Hey, a Rubik's Cube! I used to be really good at those! But you can only solve them five times. Then you have to buy another one.' Leticia: 'Five times? Er ... why's that, Neil?' Neil: 'After that, the little square stickers aren't sticky anymore.'
Mark Pett’s Lucky Cow rerun for the 27th of December, 2018. So I am dropping the strip from my routine reading. But the various appearances of Lucky Cow should remain at this link.

Mark Pett’s Lucky Cow rerun for the 27th I do intend to make this enjoyable but cancelled strip’s last appearance here. It’s a Rubik’s Cube joke. It’s one about using a solution outside the rules of the problem. And as marginal as this one, I couldn’t quite bring myself to write a paragraph about the Todd the Dinosaur strip of the 29th, which also features the Rubik’s Cube.

An anthropomorphic numeral 8 talks to the doctor about its weight and its eating. The doctor performs surgery, cutting off a loop and turning the figure into a 9. It smiles and waves, and the new 9 goes off to join its friends 2, 0, and 1.
Ryan Pagelow’s Buni for the 28th of December, 2018. Essays which mention Buni should be gathered at this link.

Ryan Pagelow’s Buni for the 28th I’ll list as the anthropomorphic-numerals joke for the week, since it did turn out to be that slow a week here. I’m a bit curious what the now-9 is figuring to do next year. I suppose that one’s easy; it’s going to be going from 3 to 4 in a couple years that’s a real problem.


The various Reading the Comics posts should all be at this link. I like to think I’ll be back to having a post this coming Sunday, and maybe a second one next week if there are enough comic strips near enough to on-topic. Thanks for reading.

Reading the Comics, November 24, 2018: Origins Edition


I’m not sure there is a theme to the back half of last week’s mathematically-based comic strips. If there is, it’s about showing some origins of things. I’ll go with that title, then.

Bill Holbrook’s On The Fastrack for the 21st is another in the curious thread of strips about Fi talking about mathematics. She’s presented as doing a good job inspiring kids to appreciate mathematics as a fun, exciting, interesting thing to think about. It’s good work. And I hope this does not sound like I am envious of a more successful, if fictional, mathematics popularizer. But I don’t see much in the strip of her doing this side job well. That is, of making the case that mathematics is worth the time spent on it. That’s a lot to ask given the confines of a syndicated daily newspaper comic strip, yes. What we can expect is some hint of what the actual good argument would look like. But this particular day’s strip rings false to me, for example. I don’t see how “here’s some pizza — but first, here’s a pop quiz” makes mathematics look as something other than a chore.

Dethany, to her boyfriend: 'Fi concludes her math talks with a demonstration of the tangible benefits of numbers. By having pizza delivered. Square pizza.' Fi, to the kids, as the pizza guy arrives: 'First, calculate how much more area you get than with a round one.'
Bill Holbrook’s On The Fastrack for the 21st of November, 2018. Essays mentioning topics raised by On The Fastrack are at this link.

Pizza area offers many ways into mathematical ideas. How the area depends on the size of the pizza, for example. How the area depends on the shape, even independently of the size. How to slice a pizza fairly, especially if it’s not to be between four or six or eight people. What is the strangest shape you could make that would give people equal areas? Just the way slices intersect at angles inspires neat little geometry problems. How you might arrange toppings opens up symmetries and tilings, which are surprisingly big areas of mathematics. Setting problems on a pizza gives them a tangibility that could help capture young minds, surely. But I can’t make myself believe that this is a conversation to have when the pizza is entering the room.

At the lottery ticket booth. Grimm: 'Hey, why do you always but lottery tickets? The odds of you winning are astronomical!' Goose: 'Yeah, but they're astronomically higher if I don't buy a ticket.'
Mike Peters’s Mother Goose and Grimm for the 22nd of November, 2018. Other essays which mention Mother Goose and Grimm should be at this link. I had thought this was a new link, but it turns out there was a strip in early 2017 and another in mid-2015 that got my attention here.

Mike Peters’s Mother Goose and Grimm for the 22nd is a lottery joke. So if we suppose this was written about the last time the Powerball jackpot reached a half-billion dollars we can work out how far ahead of publication Mike Peters is working. One solid argument against ever buying a lottery ticket is, as Grimm notes, that you have zero chance of winning. (I’m open to an argument based on expectation value. And even more, I don’t object to people spending a reasonable bit of disposable income “foolishly”.) Mother Goose argues that her chances are vastly worse if she doesn’t buy a ticket. This is true. Are her chances “astronomically” worse? … That depends. A one in three hundred million chance (to use, roughly, the Powerball odds) is so small that it won’t happen to you. Is that any different than a zero in three hundred million chance [*]? Or than a six in three hundred million chance? In any case it won’t happen to you.

[*] Do you actually have zero chance of winning if you don’t have a ticket? I say no, you don’t. Someone might give you a winning ticket. Maybe you find one as a bookmark in a library book. Maybe you find it on the street and figure, what the heck, I’ll check. Unlikely? Sure. But impossible? Hardly.

Peter: 'If you had three clams and gave one away, then I took two, what would you have?' Curls: 'A worthless reason for being in business.'
Johnny Hart’s Back to BC for the 22nd of November, 2018. It originally appeared the 27th of May, 1961. Essays which discuss topics brought up by B.C., both the current-run and the half-century-old reruns, are at this link.

Johnny Hart’s Back to BC for the 22nd has the form of the world’s oldest story problem. It could also be a joke about the discovery of the concept of zero and the struggle to understand it as a number. Given that clams are used as currency in the BC setting it also shows how finance has driven mathematical development. So the strip actually packs a fair bit of stuff into two panels. … And I’ll admit I’m not quite sure the joke parses, but if you read it quickly it looks like a good enough joke.

Fat Broad, to a dinosaur: 'How much is one and one?' The dinosaur stops a front foot twice. Then gets ready to stomp a third time. Fat Broad whaps the dinosaur senseless. Broad: 'Isn't it amazing how fast animals learn?'
Johnny Hart’s Back to BC for the 24th of November, 2018. It originally appeared the 30th of May, 1961. If this strip has inspired any essays oh wait, I already said where to find them, didn’t I? Well, you know what to look for, then.

Johnny Hart’s Back to BC for the 24th is a more obvious joke. And it’s built on the learning abilities of animals, and the number sense of animals. A large animal stomping a foot evokes, to me at least, Clever Hans. This is a horse presented in the early 20th century as being able to actually do arithmetic. The horse would be given a question and would stop his hoof enough times to get to the right answer. However good the horse’s number sense might be, he had quite good behavioral sense. It turned out — after brilliant and pioneering work in animal cognition — that Hans was observing his trainer’s body language. When Wilhelm von Osten was satisfied that there’d been the right number of stomps, the horse stopped. This is sometimes presented as Hans `merely’ taking subconscious cues from his trainer. But consider how carefully the horse must be observing an animal with a very different body, and how it must have understood cues of satisfaction. I can’t call that `mere’. And the work of tracking down a signal that von Osten himself did not know he was sending (and, apparently, never accepted that he did) is also amazing. It serves as a reminder how hard biologists and zoologists have to work.

Kid: 'How come in old paintings the perspective is really badly drawn?' Dad: 'Perspective didn't exist back then. Sometimes there'd be a whole castle right behind you . Other times you'd sit at a table and the tabletop would face away from you. That's also why portraits were badly drawn. Try holding a brush in a world without three consistent dimensions. Italian architects invented perspective to make it easier to draw buildings. What's why things suddenly look a lot nicer around the 16th century.' Kid: 'Are you sure?' Dad: 'How else do you explain that it took 10,000 years of civilization to invent Cartesian coordinates?' Kid: 'I figured people are just kinda stupid.' Dad: 'How facile.'
Zach Weinersmith’s Saturday Morning Breakfast Cereal for the 24th of November, 2018. The many essays mentioning topics raised by Saturday Morning Breakfast Cereal are at this link.

Zach Weinersmith’s Saturday Morning Breakfast Cereal for the 24th gives a bit of Dad History about perspective. And, particularly, why artists didn’t seem to use it much before the 16th century. It gets more blatantly tied to mathematics by pointing out how it took ten thousand years of civilization to get Cartesian coordinates. We can argue about how many years civilization has been around. But it does seem strange that we went along for certainly the majority of that time without Cartesian coordinates. They seem so obvious it’s almost hard to not think of them. Many good ideas have such a legacy.

It’s easy to say why older pictures didn’t use perspective, though. For the most part, artists didn’t think perspective gave them something they wanted to show. Ancient peoples knew of perspective. It’s not as if ancient peoples were any dumber than we are, or any less able to look at square tiles held at different angles and at different distances. But we can convey information about the importance of things, or the flow of action of things, using position and relative size. That can be more important than showing that yes, an artist is aware that a square building far away looks small.

I’m less sure what I know about the history of coordinate systems, though, and particularly why it took until René Descartes to describe them. We have a legend of Descartes laying in bed, watching a fly on the tiled ceiling, and realizing he could describe where the fly was by what row and column of tile it was on. (In the past I have written this as though it happened. In writing this essay I went looking for a primary source and found nobody seems to have one. I shall try not to pass it on again without being very clear that it is just a legend.) But there have been tiled floors and walls and ceilings for a very long time. There have been flies even longer. Why didn’t anyone notice this?

One answer may be that they did. We just haven’t heard about it, because it was found by someone who didn’t catch the interest of a mathematical community. There’s likely a lot of such lost mathematics out there. But still, why not? Wouldn’t anyone with a mathematical inclination see that this is plainly a great discovery? And maybe not. What made Cartesian coordinates great was the realization that arithmetic and geometry, previously seen as separate liberal arts, were duals. A problem in one had an expression as a problem in the other. If you don’t make that connection, then Cartesian coordinates don’t solve any problems you have. They’re just a new way to index things you didn’t need indexed. So that would slow down using them any.


All of my regular Reading the Comics posts should all be at this link. Tomorrow should see the posting of my next my Fall 2018 Mathematics A To Z essay. And there’s still time to put in requests for the last half-dozen letters of the alphabet.

Reading the Comics, August 18, 2018: Ragged Ends Edition


I apologize for the ragged nature of this entry, but I’ve had a ragged sort of week and it’s all I can do to keep up. Alert calendar-watchers might have figured out I would have rather had this posted on Thursday or Friday, but I couldn’t make that work. I’m trying. Thanks for your patience.

Mark Anderson’s Andertoons for the 17th feeds rumors that I just reflexively include Mark Anderson’s Andertoons in these posts whenever I see one. But it features the name of something dear to me, so that’s worthwhile. And I love etymology, although not enough to actually learn anything substantive about it. I just enjoy trivia about where some words come from, and sometimes how they change over time. (The average English word meant the exact opposite thing about two hundred years ago, and it meant something hilariously unrelated two centuries before that.)

Wavehead, talking to another student: 'I forgot to do my geometry, but I got an extra day by distracting Mrs Wilson with whether 'geo' is a root or a prefix.'
Mark Anderson’s Andertoons for the 17th of August, 2018. Also so I guess now we know Wavehead’s teacher’s name. Please make a note so that when I forget this you can tell me and I’ll act like it’s a discovery.

So I’m not sure how real word-studyers would regard the “geo” in “geometry”. The word is more or less Ancient Greek, given a bit of age and worn down into common English forms. It’s fair enough to describe it as originally meaning “land survey” or “land measure”. This might seem eccentric. But much of the early use of geometry was to figure out where things were, and how far they were from each other. It seems likely the earliest uses, for example, of the Pythagorean Theorem dealt with how to draw right angles on the surface of the Earth. And how to draw boundaries. The Greek fascination with compass-and-straightedge construction — work done without a ruler, so that you know distance only as a thing relative to other things in your figure — obscures how much of the field is about measurement.

Herman: 'I just joined a new club!' Lil: 'What's it called?' Herman: 'The society of parallel lines!' Lil: 'When do you meet?' Herman: 'Never!'
Brett Koth’s Diamond Lil for the 17th of August, 2018. Will admit that I’m at the stage in life that social clubs I don’t have to actually do anything for sound attractive.

Brett Koth’s Diamond Lil for the 17th is another geometry joke, and a much clearer one. And if there’s one thing we can say about parallel lines it’s that they don’t meet. There are some corners of geometry in which it’s convenient to say they “meet at infinity”, that is, they intersect at some point an infinite distance away. I don’t recommend bringing this up in casual conversation. I’m not sure I wanted to bring it up here.

Peter, ice skating, draws a '2' with his skates, and then falls through the ice. Other, non-Peter guy: 'Now there's a figure 8 the hard way. A 2 and a deep 6.'
Johnny Hart’s Back to BC for the 18th of August, 2018. It originally ran the 21st of February, 1961.

Johnny Hart’s Back to BC for the 18th is … hm. Well, I’ll call it a numerals joke. It’s part of the continuum of jokes made about ice skating in figure-eights.


Other essays about comic strips are at this link. When I’ve talked about Andertoons I’ve tried to make sure it turns up at this link. Essays in which I’ve discussed Diamond Lil should be at this link when there are other ones. Turns out this is a new tag. The times I’ve discussed B.C., old or new, should be at this link.

Reading the Comics, August 2, 2018: Non-Euclidean Geometry Edition


There’s really only the one strip that I talk about today that gets into non-Euclidean geometries. I was hoping to have the time to get into negative temperatures. That came up in the comics too, and it’s a subject close to my heart. But I didn’t have time to write that and so must go with what I did have. I’ve surely used “Non-Euclidean Geometry Edition” as a name before too, but that name and the date of August 2, 2018? Just as surely not.

Mark Anderson’s Andertoons for the 29th is the Mark Anderson’s Andertoons for the week, at last. Wavehead gets to be disappointed by what a numerator and denominator are. Common problem; there are many mathematics things with great, evocative names that all turn out to be mathematics things.

Both “numerator” and “denominator”, as words, trace to the mid-16th century. They come from Medieval Latin, as you might have guessed. “Denominator” parses out roughly as “to completely name”. As in, break something up into some number of equal-sized pieces. You’d need the denominator number of those pieces to have the whole again. “Numerator” parses out roughly as “count”, as in the count of how many denominator-sized pieces you have. So for all that numerator and denominator look like one another, with with the meat of the words being the letters “n-m–ator”, their centers don’t have anything to do with one another. (I would believe a claim that the way the words always crop up together encouraged them to harmonize their appearances.)

On the board, the fraction 3/4 with the numerator and denominator labelled. Wavehead: 'You know, for something that sounds like two killer robots, this is really disappointing.'
Mark Anderson’s Andertoons for the 29th of July, 2018. Poor Wavehead is never going to get over his disappointment when he learns about the Fredholm Alternative. I still insist it’s an underrated mid-70s paranoia-thriller.

Johnny Hart’s Back to BC for the 29th is a surprisingly sly joke about non-Euclidean geometries. You wouldn’t expect that given the reputation of the comic the last decade of Hart’s life. And I did misread it at first, thinking that after circumnavigating the globe Peter had come back to have what had been the right line touch the left. That the trouble was his stick wearing down I didn’t notice until I re-read.

But Peter’s problem would be there if his stick didn’t wear down. “Parallel” lines on a globe don’t exist. One can try to draw a straight line on the surface of a sphere. These are “great circles”, with famous map examples of those being the equator and the lines of longitude. They don’t keep a constant distance from one another, and they do meet. Peter’s experiment, as conducted, would be a piece of proof that they have to live on a curved surface.

Peter, holding up a Y-shaped stick: 'In proving to you rather dense individuals that parallel lines never meet I am about to embark on a heretofore unprecedented expedition which will encompass the globe. See you.' (He walks off, dragging both ends of the stick in the ground, creating parallel lines. He walks several panels; 'Fifty Thousand Miles Later' as the stick wears down and the parallel lines get less far apart ... he gets back where he started, with the stick worn down to a single ribbon, and the surviving line left.)
Johnny Hart’s Back to BC for the 29th of July, 2018. It originally ran it looks like, the 13th of August, 1961. Or I’m reading the second row, second panel wrong.

And this gets at one of those questions that bothers mathematicians, cosmologists, and philosophers. How do we know the geometry of the universe? If we could peek at it from outside we’d have some help, but that is a big if. So we have to rely on what we can learn from inside the universe. And we can do some experiments that tell us about the geometry we’re in. Peter’s line example would be one; he can use that to show the world’s curved in at least one direction. A couple more lines and he’d be confident the world was a sphere. If we could make precise enough measurements we could do better, with geometric experiments smaller than the circumference of the Earth. (Or universe.) Famously, the sum of the interior angles of a triangle tell us something about the space the triangle’s inscribed in. There are dangers in going from information about one point, or a small area, to information about the whole. But we can tell some things.

Dr Strange-y type doing mind stuff: 'Using my MENTALISTIC powers of the occult, I shall attempt to DOUBLE your brain power, Captain Victorious! Peruse the potency of ... PROFESSOR PECULIAR!' Captain Victorious: 'Mind ... reeling! So much ... information!! ... Two plus two equals ... four! Hey! It worked!' Professor Peculiar: 'I guess double was too relative a term.'
Phil Dunlap’s Ink Pen rerun for the 29th of July, 2018. This one originally ran the 21st of August, 2011.

Phil Dunlap’s Ink Pen for the 29th is another use of arithmetic as shorthand for intelligence. Might be fun to ponder how Captain Victorious would know that he was right about two plus two equalling four, if he didn’t know that already. But we all are in the same state, for mathematical truths. We know we’ve got it right because we believe we have a sound logical argument for the thing being true.

A 'Newton Enterprises' boat pulls up to a desert island. A skeleton's under the tree; beside it, a whiteboard that starts with 'Coconut' and proceeds through a few lines of text to, finally, 'F = GMm/R^2'. Caption: 'How Newton actually stumbled across his formula for the theory of gravity.'
Brian Boychuk and Ron Boychuk’s Chuckle Brothers for the 30th of July, 2018. All right, so the rubber boat is an obvious anachronism. But Newton’s pal Edmond Halley made some money building diving bells for people to excavate shipwrecks and if that doesn’t mess with your idea of what the 17th century was you’re a stronger one than I am.

Brian Boychuk and Ron Boychuk’s Chuckle Brothers for the 30th is a riff on the story of Isaac Newton and the apple. The story of Newton starting his serious thinking of gravity by pondering why apples should fall while the Moon did not is famous. And it seems to trace to Newton. We have a good account of it from William Stukeley, who in the mid-18th century wrote Memoirs of Sir Isaac Newton’s Life. Stukeley knew Newton, and claimed to get the story right from him. He also told it to his niece’s husband, John Conduitt. Whether this is what got Newton fired with the need to create such calculus and physics, or whether it was a story he composed to give his life narrative charm, is beyond my ability to say. It’s an important piece of mathematics history anyway.


If you’d like more Reading the Comics essays you can find them at this link. Some of the many essays to mention Andertoons are at this link. Other essays mentioning B.C. (vintage and current) are at this link. The comic strip Ink Pen gets its mentions at this link, although I’m surprised to learn it’s a new tag today. And the Chuckle Brothers I discuss at this link. Thank you.

Reading the Comics, June 16, 2018: No Panels Edition


My week got busier than I imagined, but it was in ways worthwhile. I apologize for running late, and for not having an essay I meant to put up here this week. But I should be back to something more normal next week. I keep saying that. Also, for what seems like a rarity, all the strips for this essay are comic strips. No panels. That won’t last, I know.

Johnny Hart’s Back to B.C. for the 14th features arithmetic as a demonstration of The Smartest Man in the World’s credentials. I understand using a bit of arithmetic as a quick check that someone has any intelligence at all. It seems to me that checking “two plus two” is more common than “one plus one”, and either is more common than, say, “one plus two” or “three plus five” or anything. I’m curious why that is, though. Might one plus one just seem too simple? Or is it the bias against odd numbers and feeling that two plus two is somehow more balanced? If only there were some smart person I could ask.

Peter(?) is by a sign reading 'The Smartest Man in the World'. Other Caveman (BC?): 'How much is 2 + 2?' Peter(?): 'Four.' BC: 'What makes day?' Peter: 'The sun.' BC: 'What made people?' (Peter looks frazzled.) BC: 'Here we go again.'
Johnny Hart’s Back to B.C. for the 14th of June, 2018. The strip originally ran the 17th of December, 1960. Thing to remember about Peter(?)’s claim is that at this time there’s like eight people in the world so, you know, yeah.

Jef Mallett’s Frazz for the 14th has a blackboard full of arithmetic as the icon of “doing a lot of school work”. Can’t say it’s age-inappropriate or anything. It’s just an efficient way to show a lot of work that’s kind of tiring to do has been done. … Also somehow one of the commenters didn’t understand the use of ‘flag’ as meaning to lose energy or enthusiasm. Huh.

[ In front of board full of multiplication problems. ] Mrs Olsen: 'Very good. Would you like to do a few more before the bell rings?' Student: 'No, thank you. It's flag day.' [ Later ] Frazz: 'What did that have to do with it?' Student: 'I was beginning to flag.'
Jef Mallett’s Frazz for the 14th of June, 2018. I apologize that I can’t remember this student’s name and I couldn’t find it on a reasonable search. Comic strip About pages need character names.

Jef Mallett’s Frazz for the 15th is a percentages joke, built on confusion between how to go from percentages to fractions and back again. Must say that I had thought 50 percent was tied well enough to one-half in ordinary language (or in phrases like splitting something fifty-fifty) that someone wouldn’t be confused by that. But everyone does miss some obvious things.

Student, to Mrs Olsen: 'If we're just going to forget 60% of this stuff over the summer, why not study only the half of it we'll remember?' [ Later ] Student: 'Annnnnd she doubled our homework.' Frazz: 'What percent of it is math now?'
Jef Mallett’s Frazz for the 15th of June, 2018. I have a similar apology for this student’s name, too. Shall happily accept information on this point.

Mark Pett’s Lucky Cow for the 16th is a probability strip. It is based on what seems obvious, that the fact of any person’s existing is an incredibly unlikely event. We can imagine restarting the universe, and letting it all develop again. And we’re forced to conclude there are so many other ways that galaxies might form and stars might come into being and planets might form and life might develop and evolution might proceed and people might meet and children might be born, and only one way that gets us here. So the chance of any of us existing is impossibly tiny. This is all consistent with the “frequentist” idea of what probability means. In that, we say the probability of a thing happening is all the ways that it could happen divided by all the ways that something could happen. (There are a bunch of technical points to go along with this.)

Clare: 'I need to win the lottery. That would solve all my problems!' Leticia: 'You know, Clare, if you think about it, we've all already *won* the lottery! Each one of us is here because of a long line of happy accidents! Eons ago, our ancestors happened to meet and have children and so on down to our parents! Really, the odds against you or me even being here are *astronomical*!' ... Clare: 'Now I see what they mean when they say winning the lottery can be a curse.'
Mark Pett’s Lucky Cow for the 16th of June, 2018. It originally ran the 20th of August, 2006.

But there are a lot of buried assumptions in there. Many of them seem reasonable. For example: could the universe unfold any differently? It seems obvious that, for example, the radius of the Earth’s orbit around the sun is arbitrary and might be anything in a band that could support life. And, surely, if the year had more or fewer days to it all human history would be different. But then this seems obvious: drop a bunch of short needles across a set of parallel straight lines. The number of needles that cross any of those lines should be arbitrary and unpredictable. Except that it is predictable; there’s a well-known formula that says how many of those needles have to cross those lines. The prediction can be lousy for a handful of needles. For millions of needles, though, it’ll be dead on. The universe won’t make sense any other way.

I can’t go so far as to say that it’s impossible for a universe to exist without me existing and just as I am. That seems egotistical. Even the needle-drop talk has room for variations on the universe. In ten million needle drops, one needle crossing more or less would not be an implausible difference. Ten or a thousand needles falling differently wouldn’t stand out. But, then, after enough needle drops? … If infinitely many needles dropped, I could say exactly what percentage of them crossed lines. (I am speaking so very casually about very difficult technical points. Please pretend I have clear answers for them.) There are deep philosophical questions about the idea of “other universes” that we have to ask if we want to take the subject seriously. But there are deep mathematical questions too.

X figure in a circle: 'DNA tests show I'm related to a Roman beauty by the name of Boderikus Maximus.' Woman: 'Good looking, was she?' X: 'Caesar himself called her a perfect 10.'
Bob Shannon’s Tough Town for the 16th of June, 2018. And the woman here is in nearly every strip and she’s not named either. The About page just talks about Rudolph, “a divorced reindeer working unhappily as a 4th grade teacher” and I think I remember him appearing in the strip back when it started. Oh, I guess that’s him in the title panel on the page, but not in the strip worth mentioning anymore.

Bob Shannon’s Tough Town for the 16th is more or less the anthropomorphized Roman Numerals joke for the week. I don’t know that there’s a strong consensus about why X was used to represent “ten”. Likely it’s impossible to prove any explanation is right. But X has settled into meaning ten, and to serve a host of other uses in typography and in symbols. Some of them are likely connected. Some are probably just coincidence.


If you’d like more of these Reading the Comics posts, you can find them in reverse chronological order at this link. If you’re interested in the comics mentioned particularly here, this page has the B.C. comics (both new and vintage). Frazz is on this page. The Lucky Cow strips are on this page. And Tough Town strips are here.

Reading the Comics, January 16, 2017: Better Workflow Edition


So one little secret of my Reading the Comics posts is I haven’t been writing them in a way that makes sense to me. To me, I should take each day’s sufficiently relevant comics, describe them in a paragraph or two, and then have a nice pile of text all ready for the posting Sunday and, if need be, later. I haven’t been doing that. I’ve let links pile up until Friday or Saturday, and then try to process them all, and if you’ve ever wondered why the first comic of the week gets 400 words about some subtlety while the last gets “this is a comic that exists”, there you go. This time around, let me try doing each day’s strips per day and see how that messes things up.

Jef Mallett’s Frazz for the 14th of January is another iteration of the “when will we ever use mathematics” complaint. The answer of “you’ll use it on the test” is unsatisfactory. But somehow, the answer of “you’ll use it to think deeply about something you had never considered before” also doesn’t satisfy. Anyway I’d like to see the idea that education is job-training abolished; I think it should be about making a person conversant with the history of human thought. That can’t be done perfectly, and we might ask whether factoring 32 is that important a piece, but it should certainly be striven for.

Ham’s Life on Earth for the 14th is a Gary Larsonesque riff on that great moment of calculus and physics history, Newton’s supposition that gravity has to follow a universally true law. I’m not sure this would have made my cut if I reviewed a week’s worth of strips at a time. Hm.

Mason Mastroianni’s B.C. for the 15th is a joke about story problem construction, and how the numbers in a story problem might be obvious nonsense. It’s also a cheap shot at animal hoarders, I suppose, but that falls outside my territory here.

Anthony Blades’s Bewley rerun for the 15th riffs on the natural number sense we all have. And we do have a number sense, remarkably. We might not be able to work out 9 times 6 instantly. But asked to pick from a list of possible values, we’re more likely to think that 58 is credible than that 78 or 38 are. It’s quite imprecise, but isn’t it amazing that it’s there at all?

Bill Amend’s FoxTrot Classics for the 15th is a story problem joke, in this case, creating one with a strong motivation for its solution to be found. The strip originally ran the 22nd of January, 1996.

Zach Weinersmith’s Saturday Morning Breakfast Cereal for the 16th is maybe marginal to include, too. It’s about the kinds of logic puzzles that mathematicians grow up reading and like to pass around. And the way you can fake out someone by presenting a problem with too obvious a solution. It’s not just professors who’ll be stymied by having the answer look too obvious, by the way. Everyone’s similarly vulnerable. To see anything, including an abstract thing like the answer to a puzzle, you need some idea of what you are looking at. If you don’t think the answer could be something that simple, you won’t see it there.

Paw: 'It's four o'clock ... what time are we going to eat?' Maw :'About five.' Paw: 'Good! That gives me two hours to work with Pokey on his arithmeteic.'
Gordon Bess’s Redeye for the 6th of September, 1971. That’s the sort of punch line that really brings out the comically-anachronistic Old West theme.

Gordon Bess’s Redeye for the 6th of September, 1971, was reprinted the 17th. It’s about the fun of teaching a subject you aren’t all that good on yourself. The mathematics is a name-drop here, but the joke wouldn’t make sense if it were about social studies.

Popeye: 'King, they's one thing I wants to know. How much is a pezozee?' King Blozo: 'Why bring that up?' Popeye: 'Yer men hired me to help lick yer emeny at a thousing pezozees a week - tha's why I'd like to know what is a pezozee.' Blozo: 'A pezozee is two pazookas.' Popeye: 'What's a pazooky?' Blozo: 'A pazooka is two pazinkas.' Popeye: 'What's a pazinky?' Blozo: 'A pazinka is two pazoonies.' Popeye: 'What's a pazeenya?' Blozo: 'Phooey! I wish you would quit following me! A pazooney is two pazeenyas.' Popeye: 'what's a pazeenya?' Blozo: 'Two pazimees.' Popeye: 'Hey! What's a pazimee worth?' Blozo: 'Absolutely nothing!' Popeye: 'Blow me down, I'm glad I ain't gettin' paid in pazimees!'
Elzie Segar’s Thimble Theatre for the 10th of August, 1931. Not listed: the rate of exchange for paczki, which reappeared this week.

Elzie Segar’s Thimble Theatre for the 10th of August, 1931, was also reprinted the 17th. It’s an old gag, even back when it was first run. But I suppose there’s some numerical-conversion mathematics to wring out of it. Given the rate of exchange, a pezozee would seem to be 24 pazimees. I’m not sure we need so many units in-between the pazimee and the pezozee, but perhaps King Blozo’s land set its units in a time when fractions were less familiar to the public. The punch line depends on the pazimee being worth nothing and, taken literally, that has sad implications for the pezozee too. If you take the King as speaking roughly, though, sixteen times a small amount is … at least a less small amount. It wouldn’t take many doublings to go from an infinitesimally tiny sum to a respectable one.

And it turns out there were enough comic strips I need to split this into two segments. So I should schedule that to appear. It’s already written and everything.

Reading the Comics, January 9, 2018: Be Squared Edition


It wasn’t just another busy week from Comic Strip Master Command. And a week busy enough for me to split the mathematics comics into two essays. It was one where I recognized one of the panels as one I’d featured before. Multiple times. Some of the comics I feature are in perpetual reruns and don’t have your classic, deep, Peanuts-style decades of archives to draw from. I don’t usually go checking my archives to see if I’ve mentioned a comic before, not unless something about it stands out. So for me to notice I’ve seen this strip repeatedly can mean only one thing: there was something a little bit annoying about it. Recognize it yet? You will.

Hy Eisman’s Popeye for the 7th of January, 2018 is an odd place for mathematics to come in. J Wellington Wimpy regales Popeye with all the intellectual topics he tried to impress his first love with, and “Euclidean postulates in the original Greek” made the cut. And, fair enough. Euclid’s books are that rare thing that’s of important mathematics (or scientific) merit and that a lay person can just pick up and read, even for pleasure. These days we’re more likely to see a division between mathematics writing that’s accessible but unimportant (you know, like, me) or that’s important but takes years of training to understand. Doing it in the original Greek is some arrogant showing-off, though. Can’t blame Carolyn for bailing on someone pulling that stunt.

Popeye: 'Did ya ever think of gittin' hitched?' Wimpy: 'Many times! I didn't plan to be a bachelor. In fact, my first love was Carolyn. While we dined on burgers at Roughhouse's she listened to my discourse on Schopenhauer, followed by my chat that included both Kafka and Camus. Then, as I walked her home, I recited Euclidean postulates in the original Greek!' Popeye: 'Y'wuz really on a roll!' Wimpy: 'When we got to her door she said, 'Wimpy, it's been a perfect evening. Please don't spoil it by EVER asking me out again!''.
Hy Eisman’s Popeye for the 7th of January, 2018. Why does Wimpy’s shirt have a belly button?

Mark O’Hare’s Citizen Dog rerun for the 7th continues last essay’s storyline about Fergus taking Maggie’s place at school. He’s having trouble understanding the story within a story problem. I sympathize.

John Hambrock’s The Brilliant Mind of Edison Lee for the 8th is set in mathematics class. And Edison tries to use a pile of mathematically-tinged words to explain why it’s okay to read a Star Wars book instead of paying attention. Or at least to provide a response the teacher won’t answer. Maybe we can make something out of this by allowing the monetary value of something to be related to its relevance. But if we allow that then Edison’s messed up. I don’t know what quantity is measured by multiplying “every Star Wars book ever written” by “all the movies and merchandise”. But dividing that by the value of the franchise gets … some modest number in peculiar units divided by a large number of dollars. The number value is going to be small. And the dimensions are obviously crazy. Edison needs to pay better attention to the mathematics.

Teacher: 'Mister Lee, what are you reading?' Edison Lee: 'The Legends of Luke Skywalker.' Teacher: 'Ah, and how would that be relevant to this math class?' Edison: 'If you take every Star Wars book ever written, multiply them by all the movies and merchandise, and divide that by the net worth of the franchise, you have a small fortune of relevance.' (Teacher looks away.) Edison thinks: 'My mouth needs a seven-second broadcast delay.'
John Hambrock’s The Brilliant Mind of Edison Lee for the 8th of January, 2018. No, I haven’t got any idea how the third panel leads to the fourth. I mean, I know what should lead from there to there — a moment of Edison realizing he’s said something so impolitic he can’t carry on — but that moment isn’t there. The teacher seems to just shrug the whole nonsense off. Something went wrong in the composing of the joke.

Johnny Hart’s B.C. for the 14th of July, 1960 shows off the famous equation of the 20th century. All part of the comic’s anachronism-comedy chic. The strip reran the 9th of January. “E = mc2” is, correctly, associated with Albert Einstein and some of his important publications of 1905. But the expression does have some curious precursors, people who had worked out the relationship (or something close to it) before Einstein and who didn’t quite know what they had. A short piece from Scientific American a couple years back describes pre-Einstein expressions of the equation from Oliver Heaviside, Henri Poincaré, and Fritz Hasenöhrl. I’m not surprised Poincaré had something close to this; it seems like he spent twenty years almost discovering Relativity. That’s all right; he did enough in dynamical systems that mathematicians aren’t going to forget him.

Tim Lachowski’s Get A Life for the 9th is at least the fourth time I’ve seen this panel since I started doing Reading the Comics posts regularly. (Previous times: the 5th of November, 2012 and the 10th of March, 2015 and the 14th of July, 2016.) I’m like this close to concluding the strip’s in perpetual rerun and I can drop it from my daily reading.

Jason Chatfield’s Ginger Meggs for the 9th draws my eye just because the blackboard lists “Prime Numbers”. Fair enough place setting, although what’s listed are 1, 3, 5, and 7. These days mathematicians don’t tend to list 1 as a prime number; it’s inconvenient. (A lot of proofs depend on their being exactly one way to factorize a number. But you can always multiply a number by ‘1’ a couple more times without changing its value. So ‘6’ is 3 times 2, but it’s also 3 times 2 times 1, or 3 times 2 times 1 times 1, or 3 times 2 times 1145,388,434,247. You can write around that, but it’s easier to define ‘1’ as not a prime.) But it could be defended. I can’t think any reason to leave ‘2’ off a list of prime numbers, though. I think Chatfield conflated odd and prime numbers. If he’d had a bit more blackboard space we could’ve seen whether the next item was 9 or 11 and that would prove the matter.

Paul Trap’s Thatababy for the 9th uses arithmetic — square roots — as the kind of thing to test whether a computer’s working. Everyone has their little tests like this. My love’s father likes to test whether the computer knows of the band Walk The Moon or of Christine Korsgaard (a prominent philosopher in my love’s specialty). I’ve got a couple words I like to check dictionaries for. Of course the test is only any good if you know what the answer should be, and what’s the actual square root of 3,278? Goodness knows. It’s got to be between 50 (50 squared is 25 hundred) and 60 (60 squared is 36 hundred). Since 3,278 is so much closer 3,600 than 2,500 its square root should be closer to 60 than to 50. So 57-point-something is plausible. Unfortunately square roots don’t lend themselves to the same sorts of tricks from reading the last digit that cube roots do. And 3,278 isn’t a perfect square anyway. Alexa is right on this one. Also about the specific gravity of cobalt, at least if Wikipedia is right and not conspiring with the artificial intelligences on this one. Catch you in 2021.

Charles Schulz’s Peanuts for the 8th of October, 1953, is about practical uses of mathematics. It got rerun on the 9th of January.

Reading the Comics, July 15, 2017: Dawn Of Mathematics Jokes


So I try to keep up with nearly all the comic strips run on Comics Kingdom and on GoComics. This includes some vintage strips: take some ancient comic like Peanuts or Luann and rerun it, day at a time, from the beginning. This is always enlightening. It’s always interesting to see a comic in that first flush of creative energy, before the characters have quite settled in and before the cartoonist has found stock jokes that work so well they don’t even have to be jokes anymore. One of the most startling cases for me has been Johnny Hart’s B.C. which, in its Back To B.C. incarnation, has been pretty well knocking it out of the park.

Not this week, I’m sad to admit. This week it’s been doing a bunch of mathematics jokes, which is what gives me my permission to talk about it here. The jokes have been, eh, the usual, given the setup. A bit fresher, I suppose, for the characters in the strip having had fewer of their edges worn down by time. Probably there’ll be at least one that gets a bit of a grin.

Back To B.C. for the 11th sets the theme going. On the 12th it gets into word problems. And then for the 13th of July it turns violent and for my money funny.

Mark Tatulli’s Heart of the City has a number appear on the 12th. That’s been about as much mathematical content as Heart’s experience at Math Camp has taken. The story’s been more about Dana, her camp friend, who’s presented as good enough at mathematics to be bored with it, and the attempt to sneak out to the nearby amusement park. What has me distracted is wondering what amusement park this could be, given that Heart’s from Philadelphia and the camp’s within bus-trip range and in the forest. I can’t rule out that it might be Knoebels Amusement Park, in Elysburg, Pennsylvania, in which case Heart and Dana are absolutely right to sneak out of camp because it is this amazing place.

TV Chef: 'Mix in one egg.' Cookie: 'See ... for us that would be 200 eggs.' TV Chef: 'Add a cup of flour.' Cookie: '200 cups of flour.' TV CHef: 'Now bake for two hours.' Cookie to Sarge: 'It'll be ready next week.'
Mort Walker’s Beetle Bailey Vintage for the 21st of December, 1960 and rerun the 14th of July, 2017. Wow, I remember when they’d put recipes like this on the not-actual-news segment of the 5:00 news or so, and how much it irritated me that there wasn’t any practical way to write down the whole thing and even writing down the address to mail in for the recipe seemed like too much, what with how long it took on average to find a sheet of paper and a writing tool. In hindsight, I don’t know why this was so hard for me.

Mort Walker’s Beetle Bailey Vintage for the 21st of December, 1960 was rerun the 14th. I can rope this into mathematics. It’s about Cookie trying to scale up a recipe to fit Camp Swampy’s needs. Increasing the ingredient count is easy, or at least it is if your units scale nicely. I wouldn’t want to multiple a third of a teaspoon by 200 without a good stretching beforehand and maybe a rubdown afterwards. But the time needed to cook a multiplied recipe, that gets mysterious. As I understand it — the chemistry of cooking is largely a mystery to me — the center of the trouble is that to cook a thing, heat has to reach throughout the interior. But heat can only really be applied from the surfaces of the cooked thing. (Yes, theoretically, a microwave oven could bake through the entire volume of something. But this would require someone inventing a way to bake using a microwave.) So we must balance the heat that can be applied over what surface to the interior volume and any reasonable time to cook the thing. Won’t deny that at some point it seems easier to just make a smaller meal.

Zach Weinersmith’s Saturday Morning Breakfast Cereal for the 14th goes to the old “inference testing” well again. This comes up from testing whether something strange is going on. Measure something in a sample. Is the result appreciably different from what would be a plausible result if nothing interesting is going on? The null hypothesis is the supposition that there isn’t anything interesting going on: the measurement’s in the range of what you’d expect given that the world is big and complicated. I’m not sure what the physicist’s exact experiment would have been. I suppose it would be something like “you lose about as much heat through your head as you do any region of skin of about the same surface area”. So, yeah, freezing would be expected, considering.

Percy Crosby’s Skippy for the 17th of May, 1930, and rerun the 15th, maybe doesn’t belong here. It’s just about counting. Never mind. I smiled at it, and I’m a fan of the strip. Give it a try; it’s that rare pre-Peanuts comic that still feels modern.

And, before I forget: Have any mathematics words or terms you’d like to have explained? I’m doing a Summer 2017 A To Z and taking requests! Please offer them over there, for convenience. I mean mine.

Reading the Comics, June 26, 2017: Deluge Edition, Part 1


So this past week saw a lot of comic strips with some mathematical connection put forth. There were enough just for the 26th that I probably could have done an essay with exclusively those comics. So it’s another split-week edition, which suits me fine as I need to balance some of my writing loads the next couple weeks for convenience (mine).

Tony Cochrane’s Agnes for the 25th of June is fun as the comic strip almost always is. And it’s even about estimation, one of the things mathematicians do way more than non-mathematicians expect. Mathematics has a reputation for precision, when in my experience it’s much more about understanding and controlling error methods. Even in analysis, the study of why calculus works, the typical proof amounts to showing that the difference between what you want to prove and what you can prove is smaller than your tolerance for an error. So: how do we go about estimating something difficult, like, the number of stars? If it’s true that nobody really knows, how do we know there are some wrong answers? And the underlying answer is that we always know some things, and those let us rule out answers that are obviously low or obviously high. We can make progress.

Russell Myers’s Broom Hilda for the 25th is about one explanation given for why time keeps seeming to pass faster as one age. This is a mathematical explanation, built on the idea that the same linear unit of time is a greater proportion of a young person’s lifestyle so of course it seems to take longer. This is probably partly true. Most of our senses work by a sense of proportion: it’s easy to tell a one-kilogram from a two-kilogram weight by holding them, and easy to tell a five-kilogram from a ten-kilogram weight, but harder to tell a five from a six-kilogram weight.

As ever, though, I’m skeptical that anything really is that simple. My biggest doubt is that it seems to me time flies when we haven’t got stories to tell about our days, when they’re all more or less the same. When we’re doing new or exciting or unusual things we remember more of the days and more about the days. A kid has an easy time finding new things, and exciting or unusual things. Broom Hilda, at something like 1500-plus years old and really a dour, unsociable person, doesn’t do so much that isn’t just like she’s done before. Wouldn’t that be an influence? And I doubt that’s a complete explanation either. Real things are more complicated than that yet.

Mac and Bill King’s Magic In A Minute for the 25th features a form-a-square puzzle using some triangles. Mathematics? Well, logic anyway. Also a good reminder about open-mindedness when you’re attempting to construct something.

'Can you tell me how much this would be with the discount?' 'It would be ... $17.50.' 'How did you do that so fast?' 'Ten percent of 25 is $2.50 ... times three is $7.50 ... round that to $8.00 ... $25 minus $8 is $17 ... add back the 50 cents and you get $17.50.' 'So you're like a math genius?' (Thinking) 'I never thought so before I started working here.'
Norm Feuti’s Retail for the 26th of June, 2017. So, one of my retail stories that I might well have already told because I only ever really had one retail job and there’s only so many stories you get working a year and a half in a dying mall’s book store. I was a clerk at Walden Books. The customer wanted to know for this book whether the sticker’s 10 percent discount was taken before or after the state’s 6 percent sales tax was applied. I said I thought the discount taken first and then tax applied, but it didn’t matter if I were wrong as the total would be the same amount. I calculated what it would be. The customer was none too sure about this, but allowed me to ring it up. The price encoded in the UPC was wrong, something like a dollar more than the cover price, and the subtotal came out way higher. The customer declared, “See?” And wouldn’t have any of my explaining that he was hit by a freak event. I don’t remember other disagreements between the UPC price and the cover price, but that might be because we just corrected the price and didn’t get a story out of it.

Norm Feuti’s Retail for the 26th is about how you get good at arithmetic. I suspect there’s two natural paths; you either find it really interesting in your own right, or you do it often enough you want to find ways to do it quicker. Marla shows the signs of learning to do arithmetic quickly because she does it a lot: turning “30 percent off” into “subtract ten percent three times over” is definitely the easy way to go. The alternative is multiplying by seven and dividing by ten and you don’t want to multiply by seven unless the problem gives a good reason why you should. And I certainly don’t fault the customer not knowing offhand what 30 percent off $25 would be. Why would she be in practice doing this sort of problem?

Johnny Hart’s Back To B.C. for the 26th reruns the comic from the 30th of December, 1959. In it … uh … one of the cavemen guys has found his calendar for the next year has too many days. (Think about what 1960 was.) It’s a common problem. Every calendar people have developed has too few or too many days, as the Earth’s daily rotations on its axis and annual revolution around the sun aren’t perfectly synchronized. We handle this in many different ways. Some calendars worry little about tracking solar time and just follow the moon. Some calendars would run deliberately short and leave a little stretch of un-named time before the new year started; the ancient Roman calendar, before the addition of February and January, is famous in calendar-enthusiast circles for this. We’ve now settled on a calendar which will let the nominal seasons and the actual seasons drift out of synch slowly enough that periodic changes in the Earth’s orbit will dominate the problem before the error between actual-year and calendar-year length will matter. That’s a pretty good sort of error control.

8,978,432 is not anywhere near the number of days that would be taken between 4,000 BC and the present day. It’s not a joke about Bishop Ussher’s famous research into the time it would take to fit all the Biblically recorded events into history. The time is something like 24,600 years ago, a choice which intrigues me. It would make fair sense to declare, what the heck, they lived 25,000 years ago and use that as the nominal date for the comic strip. 24,600 is a weird number of years. Since it doesn’t seem to be meaningful I suppose Hart went, simply enough, with a number that was funny just for being riotously large.

Mark Tatulli’s Heart of the City for the 26th places itself on my Grand Avenue warning board. There’s plenty of time for things to go a different way but right now it’s set up for a toxic little presentation of mathematics. Heart, after being grounded, was caught sneaking out to a slumber party and now her mother is sending her to two weeks of Math Camp. I’m supposing, from Tatulli’s general attitude about how stuff happens in Heart and in Lio that Math Camp will not be a horrible, penal experience. But it’s still ominous talk and I’m watching.

Brian Fies’s Mom’s Cancer story for the 26th is part of the strip’s rerun on GoComics. (Many comic strips that have ended their run go into eternal loops on GoComics.) This is one of the strips with mathematical content. The spatial dimension of a thing implies relationships between the volume (area, hypervolume, whatever) of a thing and its characteristic linear measure, its diameter or radius or side length. It can be disappointing.

Nicholas Gurewitch’s Perry Bible Fellowship for the 26th is a repeat of one I get on my mathematics Twitter friends now and then. Should warn, it’s kind of racy content, at least as far as my usual recommendations here go. It’s also a little baffling because while the reveal of the unclad woman is funny … what, exactly, does it mean? The symbols don’t mean anything; they’re just what fits graphically. I think the strip is getting at Dr Loring not being able to see even a woman presenting herself for sex as anything but mathematics. I guess that’s funny, but it seems like the idea isn’t quite fully developed.

Zach Weinersmith’s Saturday Morning Breakfast Cereal Again for the 26th has a mathematician snort about plotting a giraffe logarithmically. This is all about representations of figures. When we plot something we usually start with a linear graph: a couple of axes perpendicular to one another. A unit of movement in the direction of any of those axes represents a constant difference in whatever that axis measures. Something growing ten units larger, say. That’s fine for many purposes. But we may want to measure something that changes by a power law, or that grows (or shrinks) exponentially. Or something that has some region where it’s small and some region where it’s huge. Then we might switch to a logarithmic plot. Here the same difference in space along the axis represents a change that’s constant in proportion: something growing ten times as large, say. The effective result is to squash a shape down, making the higher points more nearly flat.

And to completely smother Weinersmith’s fine enough joke: I would call that plot semilogarithmically. I’d use a linear scale for the horizontal axis, the gazelle or giraffe head-to-tail. But I’d use a logarithmic scale for the vertical axis, ears-to-hooves. So, linear in one direction, logarithmic in the other. I’d be more inclined to use “logarithmic” plots to mean logarithms in both the horizontal and the vertical axes. Those are useful plots for turning up power laws, like the relationship between a planet’s orbital radius and the length of its year. Relationships like that turn into straight lines when both axes are logarithmically spaced. But I might also describe that as a “log-log plot” in the hopes of avoiding confusion.

Reading the Comics, February 11, 2017: Trivia Edition


And now to wrap up last week’s mathematically-themed comic strips. It’s not a set that let me get into any really deep topics however hard I tried overthinking it. Maybe something will turn up for Sunday.

Mason Mastroianni, Mick Mastroianni, and Perri Hart’s B.C. for the 7th tries setting arithmetic versus celebrity trivia. It’s for the old joke about what everyone should know versus what everyone does know. One might question whether Kardashian pet eating habits are actually things everyone knows. But the joke needs some hyperbole in it to have any vitality and that’s the only available spot for it. It’s easy also to rate stuff like arithmetic as trivia since, you know, calculators. But it is worth knowing that seven squared is pretty close to 50. It comes up when you do a lot of estimates of calculations in your head. The square root of 10 is pretty near 3. The square root of 50 is near 7. The cube root of 10 is a little more than 2. The cube root of 50 a little more than three and a half. The cube root of 100 is a little more than four and a half. When you see ways to rewrite a calculation in estimates like this, suddenly, a lot of amazing tricks become possible.

Leigh Rubin’s Rubes for the 7th is a “mathematics in the real world” joke. It could be done with any mythological animals, although I suppose unicorns have the advantage of being relatively easy to draw recognizably. Mermaids would do well too. Dragons would also read well, but they’re more complicated to draw.

Mark Pett’s Mr Lowe rerun for the 8th has the kid resisting the mathematics book. Quentin’s grounds are that how can he know a dated book is still relevant. There’s truth to Quentin’s excuse. A mathematical truth may be universal. Whether we find it interesting is a matter of culture and even fashion. There are many ways to present any fact, and the question of why we want to know this fact has as many potential answers as it has people pondering the question.

Zach Weinersmith’s Saturday Morning Breakfast Cereal for the 8th is a paean to one of the joys of numbers. There is something wonderful in counting, in measuring, in tracking. I suspect it’s nearly universal. We see it reflected in people passing around, say, the number of rivets used in the Chrysler Building or how long a person’s nervous system would reach if stretched out into a line or ever-more-fanciful measures of stuff. Is it properly mathematics? It’s delightful, isn’t that enough?

Scott Hilburn’s The Argyle Sweater for the 10th is a Fibonacci Sequence joke. That’s a good one for taping to the walls of a mathematics teacher’s office.

'Did you ever take a date to a drive-in movie in high school?' 'Once, but she went to the concession stand and never came back.' 'Did you wonder why?' 'Yeah, but I kept on doing my math homework.'
Bill Rechin’s Crock rerun for the 11th of February, 2017. They actually opened a brand-new drive-in theater something like forty minutes away from us a couple years back. We haven’t had the chance to get there. But we did get to one a fair bit farther away where yes, we saw Turbo, that movie about the snail that races in the Indianapolis 500. The movie was everything we hoped for and it’s just a shame Roger Ebert died too young to review it for us.

Bill Rechin’s Crock rerun for the 11th is a name-drop of mathematics. Really anybody’s homework would be sufficiently boring for the joke. But I suppose mathematics adds the connotation that whatever you’re working on hasn’t got a human story behind it, the way English or History might, and that it hasn’t got the potential to eat, explode, or knock a steel ball into you the way Biology, Chemistry, or Physics have. Fair enough.

Early April’s Math Comics


I had started to think the mathematics references in the comics pages were fading out and I might not have an installment to offer anytime soon. Then, on April 3, Pab Sugenis’s The New Adventures of Queen Victoria — a clip art comic strip which supposes the reader will recognize an illustration of King Edward VI — skipped its planned strip for the day (Sugenis’s choice, he says) and ran a Fuzzy Bunny Time strip calling on pretty much the expected rabbits and mathematics comic strip. (Some people in the Usenet group alt.fan.cecil-adams, which I read reliably and write to occasionally, say Sugenis was briefly a regular; perhaps so, but I don’t remember.) This would start a bumper crop of math strips for the week.

Continue reading “Early April’s Math Comics”

%d bloggers like this: