Reading the Comics, August 10, 2019: In Security Edition


There were several more comic strips last week worth my attention. One of them, though, offered a lot for me to write about, packed into one panel featuring what comic strip fans call the Wall O’ Text.

Bea R’s In Security for the 9th is part of a storyline about defeating an evil “home assistant”. The choice of weapon is Michaela’s barrage of questions, too fast and too varied to answer. There are some mathematical questions tossed in the mix. The obvious one is “zero divided by two equals zero, but why’z two divided by zero called crazy town?” Like with most “why” mathematics questions there are a range of answers.

Evil Alexa: 'I ordered a spanking for you: express.' Sedine: 'DIE!' Michaela: 'How 'we defeat this evil genius? (To the home-assistant) What's the diffrence between wrong and right? Who's got better fries, McD or BK? Why's a ball round? Is a wingless fly a 'walk'? Why'z all this communism so capitalistic? If Jeff Bezos is so rich why'zint he abel to own a toupee? Zero divded by two equals zero, but why'z two divided by zero called crazy town? So if infinity is forever, isn't that crazy too? If reality is a human construck why does my mommy act so normal? Tell me!' Sputtering Alexia: 'I - I must compute!'
Bea R’s In Security for the 9th of August, 2019. This is a new comic strip for these parts. So this essay and any future ones which explore topics raised by In Security are to be be at this link.

The obvious one, I suppose, is to appeal to intuition. Think of dividing one number by another by representing the numbers with things. Start with a pile of the first number of things. Try putting them into the second number of bins. How many times can you do this? And then you can pretty well see that you can fill two bins with zero things zero times. But you can fill zero bins with two things — well, what is filling zero bins supposed to mean? And that warns us that dividing by zero is at least suspicious.

That’s probably enough to convince a three-year-old, and probably most sensible people. If we start getting open-mined about what it means to fill no containers, we might say, well, why not have two things fill the zero containers zero times over, or once over, or whatever convenient answer would work? And here we can appeal to mathematical logic. Start with some ideas that seem straightforward. Like, that division is the inverse of multiplication. That addition and multiplication work like you’d guess from the way integers work. That distribution works. Then you can quickly enough show that if you allow division by zero, this implies that every number equals every other number. Since it would be inconvenient for, say, “six” to also equal “minus 113,847,506 and three-quarters” we say division by zero is the problem.

This is compelling until you ask what’s so great about addition and multiplication as we know them. And here’s a potentially fruitful line of attack. Coming up with alternate ideas for what it means to add or to multiply are fine. We can do this easily with modular arithmetic, that thing where we say, like, 5 + 1 equals 0 all over again, and 5 + 2 is 1 and 5 + 3 is 2. This can create a ring, and it can offer us wild ideas like “3 times 2 equals 0”. This doesn’t get us to where dividing by zero means anything. But it hints that maybe there’s some exotic frontier of mathematics in which dividing by zero is good, or useful. I don’t know of one. But I know very little about topics like non-standard analysis (where mathematicians hypothesize non-negative numbers that are not zero, but are also smaller than any positive number) or structures like surreal numbers. There may be something lurking behind a Quanta Magazine essay I haven’t read even though they tweet about it four times a week. (My twitter account is, for some reason, not loading this week.)

Michaela’s questions include a couple other mathematically-connected topics. “If infinity is forever, isn’t that crazy, too?” Crazy is a loaded word and probably best avoided. But there are infinity large sets of things. There are processes that take infinitely many steps to complete. Please be kind to me in my declaration “are”. I spent five hundred words on “two divided by zero”. I can’t get into that it means for a mathematical thing to “exist”. I don’t know. In any event. Infinities are hard and we rely on them. They defy our intuition. Mathematicians over the 19th and 20th centuries worked out fairly good tools for handling these. They rely on several strategies. Most of these amount to: we can prove that the difference between “infinitely many steps” and “very many steps” can be made smaller than any error tolerance we like. And we can say what “very many steps” implies for a thing. Therefore we can say that “infinitely many steps” gives us some specific result. A similar process holds for “infinitely many things” instead of “infinitely many steps”. This does not involve actually dealing with infinity, not directly. It involves dealing with large numbers, which work like small numbers but longer. This has worked quite well. There’s surely some field of mathematics about to break down that happy condition.

And there’s one more mathematical bit. Why is a ball round? This comes around to definitions. Suppose a ball is all the points within a particular radius of a center. What shape that is depends on what you mean by “distance”. The common definition of distance, the “Euclidean norm”, we get from our physical intuition. It implies this shape should be round. But there are other measures of distance, useful for other roles. They can imply “balls” that we’d say were octahedrons, or cubes, or rounded versions of these shapes. We can pick our distance to fit what we want to do, and shapes follow.

I suspect but do not know that it works the other way, that if we want a “ball” to be round, it implies we’re using a distance that’s the Euclidean measure. I defer to people better at normed spaces than I am.

Wavehead, standing in front of a digital blackboard which has the problem 3 + 5 on it: 'I'm just saying, with all the computing power in this electronic board, I bet it could take care of this itself.'
Mark Anderson’s Andertoons for the 10th of August, 2019. The handful of times that I’ve mentioned explore Andertoons around here can be found at this link.

Mark Anderson’s Andertoons for the 10th is the Mark Anderson’s Andertoons for the week. It’s also a refreshing break from talking so much about In Security. Wavehead is doing the traditional kid-protesting-the-chalkboard-problem. This time with an electronic chalkboard, an innovation that I’ve heard about but never used myself.

Molly: 'We'll play after I finish my homework. I'm studying pi.' Bear: (Panel filled with the word GUSH! His mouth dangles open, and he drools.) 'You said pie!!'
Bob Scott’s Bear With Me for the 10th of August, 2019. Appearances by Bear With Me should be at this link. This strip originally ran the 15th of October, 2015, when the comic was titled Molly and the Bear.

Bob Scott’s Bear With Me for the 10th is the Pi Day joke for the week.


And that last one seemed substantial enough to highlight. There were even slighter strips. Among them: Mark Anderson’s Andertoons for the 4th features latitude and longitude, the parts of spherical geometry most of us understand. At least feel we understand. Jim Toomey’s Sherman’s Lagoon for the 8th mentions mathematics as the homework parents most dread helping with. Larry Wright’s Motley rerun for the 10th does a joke about a kid being bad at geography and at mathematics.


And that’s this past week’s mathematics comics. Reading the Comics essays should all be gathered at this link. Thanks for reading this far.

Reading the Comics, February 13, 2019: Light Geometry Edition


Comic Strip Master Command decided this would be a light week, with about six comic strips worth discussing. I’ll go into four of them here, and in a day or two wrap up the remainder. There were several strips that didn’t quite rate discussion, and I’ll share those too. I never can be sure what strips will be best taped to someone’s office door.

Alex Hallatt’s Arctic Circle for the 10th was inspired by a tabular iceberg that got some attention in October 2018. It looked surprisingly rectangular. Smoother than we expect natural things to be. My first thought about this strip was to write about crystals. The ways that molecules can fit together may be reflected in how the whole structure looks. And this gets us to studying symmetries.

Ed Penguin 'Did you see the perfectly rectangular iceberg?' Lenny Lemming: 'Yes, but I've seen perfect triangles, rhomboids, and octagons, too.' (Oscar Penguin is startled. He walks over to Frank, who is chiseling out some kind of octagonal prism.) Oscar: 'Ok, Frank, I know I said you needed a hobby ... ' Frank: 'Let's see them explain THIS one with science.'
Alex Hallatt’s Arctic Circle for the 10th of February, 2019. Essays in which I discuss Arctic Circle should be at this link.

But I got to another thought. We’re surprised to see lines in nature. We know what lines are, and understand properties of them pretty well. Even if we don’t specialize in geometry we can understand how we expect them to work. I don’t know how much of this is a cultural artifact: in the western mathematics tradition lines and polygons and circles are taught a lot, and from an early age. My impression is that enough different cultures have similar enough geometries, though. (Are there any societies that don’t seem aware of the Pythagorean Theorem?) So what is it that has got so many people making perfect lines and circles and triangles and squares out of crooked timbers?

Broom Hilda: 'I'm a winner! I won $18 in the lottery!' Gaylord: 'How much did you spend on tickets?' Hilda: '$20.' Gaylord: 'So you're actually a loser!' Hilda: 'Well, I guess you could say that, but I wish you hadn't!'
Russell Myers’s Broom Hilda for the 13th of February, 2019. Essays inspired by Broom Hilda should be gathered at this link.

Russell Myers’s Broom Hilda for the 13th is a lottery joke. Also, really, an accounting joke. Most of the players of a lottery will not win, of course. Nearly none of them will win more than they’ve paid into the lottery. If they didn’t, there would be an official inquiry. So, yes, nearly all people, even those who win money at the lottery, would have had more money if they skipped playing altogether.

Where it becomes an accounting question is how much did Broom Hilda expect to have when the week was through? If she planned to spend $20 on lottery tickets, and got exactly that? It seems snobbish to me to say that’s a dumber way to spend twenty bucks than, say, buying twenty bucks worth of magazines that you’ll throw away in a month would be. Or having dinner at a fast-casual place. Or anything else that you like doing even though it won’t leave you, in the long run, any better off. Has she come out ahead? That depends where she figures she should be.

Caption: Transcendental Eric achieves a higher plane. It shows a shaded, spherical Eric in a three-dimensional space, while below him a square asks some other polygon, 'Where's Eric gone to?'
Eric the Circle for the 13th of February, 2019, this one by Alabama_Al. Appearances by Eric the Circle, whoever the writer, should be at this link.

Eric the Circle for the 13th, this one by Alabama_Al, is a plane- and solid-geometry joke. This gets it a bit more solidly on-topic than usual. But it’s still a strip focused on the connotations of mathematically-connected terms. There’s the metaphorical use of the ‘plane’ as in the thing people perceive as reality. There’s conflation between the idea of a ‘higher plane’ and ‘higher dimensions’. Also somewhere in here is the idea that ‘higher’ and ‘more’ dimensions of space are the same thing. ‘Transcendental’ here is used in the common English sense of surpassing something. ‘Transcendental’ has a mathematical definition too. That one relates to polynomials, because everything in mathematics is about polynomials. And, of course, one of the two numbers we know to be transcendental, and that people have any reason to care about, is π, which turns up all over circles.

Joey: 'Mom, can I have a cookie?' Mom: 'Joey, you had two cookies this morning, three at lunch, and one an hour ago! Now how many is that?' Joey: 'I changed my mind.' (Thinking) 'No cookie is worth a pop quiz in math.'
Larry Wright’s Motley for the 13th of February, 2019. It originally ran in 1988, I believe on the same date. When I have written about Motley the results should appear at this link. In transcribing the strip for the alt-text here I was getting all ready to grumble that I didn’t know the kid’s name, and the strip is so old and minor that nobody has a cast list on it. Then I noticed, oh, yes, Mom says what the kid’s name is.

Larry Wright’s Motley for the 13th riffs on the form of a story problem. Joey’s mother does ask something that seems like a plausible addition problem. I’m a bit surprised he hadn’t counted all the day’s cookies already, but perhaps he doesn’t dwell on past snacks.


This and all my Reading the Comics posts should appear at this link. Thanks for looking at my comments.

Reading the Comics, January 5, 2019: Start of the Year Edition


With me wrapping up the mathematically-themed comic strips that ran the first of the year, you can see how far behind I’m falling keeping everything current. In my defense, Monday was busier than I hoped it would be, so everything ran late. Next week is looking quite slow for comics, so maybe I can catch up then. I will never catch up on anything the rest of my life, ever.

Scott Hilburn’s The Argyle Sweater for the 2nd is a bit of wordplay about regular and irregular polygons. Many mathematical constructs, in geometry and elsewhere, come in “regular” and “irregular” forms. The regular form usually has symmetries that make it stand out. For polygons, this is each side having the same length, and each interior angle being congruent. Irregular is everything else. The symmetries which constrain the regular version of anything often mean we can prove things we otherwise can’t. But most of anything is the irregular. We might know fewer interesting things about them, or have a harder time proving them.

Teacher: 'Well, class, who'd like to show Mr Hoffmeyer how to correctly make an irregular polygon regular?' On the blackboard is an irregular pentagon and, drawn by Mr Hoffmeyer, a box of Ex-Lax.
Scott Hilburn’s The Argyle Sweater for the 2nd of January, 2019. The many appearances of Argyle Sweater in these pages are at this link.

I’m not sure what the teacher would be asking for in how to “make an irregular polygon regular”. I mean if we pretend that it’s not setting up the laxative joke. I can think of two alternatives that would make sense. One is to draw a polygon with the same number of sides and the same perimeter as the original. The other is to draw a polygon with the same number of sides and the same area as the original. I’m not sure of the point of either. I suppose polygons of the same area have some connection to quadrature, that is, integration. But that seems like it’s higher-level stuff than this class should be doing. I hate to question the reality of a comic strip but that’s what I’m forced to do.

Mutt, to Jeff in the hospital bed: 'Don't be afraid! Surgery on the tonsils is very simple!' Doctor: 'Don't you worry about the results!' Jeff: 'How do you know I'll be all right?' Doctor: 'Well, I lost my last eleven patients! So if the law of probabilities doesn't lie, you'll be all right! May I do something for you before I begin?' Jeff: 'Oh, yes, Doc! Help me put on my trousers and my jacket!'
Bud Fisher’s Mutt and Jeff rerun for the 4th of January, 2019. The several appearances of Mutt and Jeff in these pages are at this link.

Bud Fisher’s Mutt and Jeff rerun for the 4th is a gambler’s fallacy joke. Superficially the gambler’s fallacy seems to make perfect sense: the chance of twelve bad things in a row has to be less than the chance of eleven bad things in a row. So after eleven bad things, the twelfth has to come up good, right? But there’s two ways this can go wrong.

Suppose each attempted thing is independent. In this case, what if each patient is equally likely to live or die, regardless of what’s come before? And in that case, the eleven deaths don’t make it more likely that the next will live.

Suppose each attempted thing is not independent, though. This is easy to imagine. Each surgery, for example, is a chance for the surgeon to learn what to do, or not do. He could be getting better, that is, more likely to succeed, each operation. Or the failures could reflect the surgeon’s skills declining, perhaps from overwork or age or a loss of confidence. Impossible to say without more data. Eleven deaths on what context suggests are low-risk operations suggest a poor chances of surviving any given surgery, though. I’m on Jeff’s side here.

On the blackboard: 'Ratios: Apples 9, Oranges 6'. Wavehead, to teacher: 'Technically the ratio is 3:2, but as a practical matter we shouldn't even really be considering this.'
Mark Anderson’s Andertoons for the 5th of January, 2019. The amazingly many appearances of Andertoons in these pages are at this link.

Mark Anderson’s Andertoons for the 5th is a welcome return of Wavehead. It’s about ratios. My impression is that ratios don’t get much attention in themselves anymore, except to dunk on stupid Twitter comments. It’s too easy to jump right into fractions, and division. Ratios underlie this, at least historically. It’s even in the name, ‘rational numbers’.

Wavehead’s got a point in literally comparing apples and oranges. It’s at least weird to compare directly different kinds of things. This is one of those conceptual gaps between ancient mathematics and modern mathematics. We’re comfortable stripping the units off of numbers, and working with them as abstract entities. But that does mean we can calculate things that don’t make sense. This produces the occasional bit of fun on social media where we see something like Google trying to estimate a movie’s box office per square inch of land in Australia. Just because numbers can be combined doesn’t mean they should be.

Kid: 'Dad, I need help with a math problem. If striking NFL players who get $35,000 a game are replaced by scab players who get $1,000 a game ... what will be the point spread in a game between the Lions and the Packers?'
Larry Wright’s Motley rerun for the 5th of January, 2019. The occasional appearances of Motley in these pages are at this link.

Larry Wright’s Motley rerun for the 5th has the form of a story problem. And one timely to the strip’s original appearance in 1987, during the National Football League players strike. The setup, talking about the difference in weekly pay between the real players and the scabs, seems like it’s about the payroll difference. The punchline jumps to another bit of mathematics, the point spread. Which is an estimate of the expected difference in scoring between teams. I don’t know for a fact, but would imagine the scab teams had nearly meaningless point spreads. The teams were thrown together extremely quickly, without much training time. The tools to forecast what a team might do wouldn’t have the data to rely on.


The at-least-weekly appearances of Reading the Comics in these pages are at this link.

Reading the Comics, October 6, 2018: Square Root of 144 Edition


And I have three last strips from last week to talk about. For those curious, I have ten comics for this week that I flagged for mention, at least before reading the Saturday GoComics pages. So that will probably be two or three installments next week. It’ll depend how many Saturday GoComics strips raise a point I feel like discussing.

Jim Toomey’s Sherman’s Lagoon for the 5th uses arithmetic as the archetypical homework problem that’s short enough to fit in a panel but also too hard for an adult to do. And, neatly, easy for a computer to do. Were I either shark here I’d have reasoned out the square root of 144 something like this: they’re not getting homework where they’d be asked the square root of something that wasn’t a perfect square. So it’s got to be a whole number. 144 is between 100 and 400, so it’s got to be the square root of something between 10 and 20. 144 is pretty close to 100, so 144’s square root is probably close to 10. The square of 1 is 1, so 11 squared has to be one-hundred-something-and-one. The square of 2 is 4, so 12 squared has to be one-hundred-something-and-four. The square of 3 is 9, so 13 squared has to be one-hundred-something-and-nine. The square of 4 is 16, so 14 squared has to be at least one-hundred-something-and-six. And by then we’re getting pretty far from 10. So the only plausible candidate is 12. Test that out and, what do you know, there it is.

Herman: 'Dad, can you help me with my math homework?' Sherman: 'Highly doubtful. But I'm sure Alexa can. Ask her anything.' Herman: 'Alexa, what's the square root of 144?' Alexa: 'The square root of 144 is 12.' Herman: 'Wow. She's good. has Mom finally decided to replace you?' Sherman: 'Should I be worried?'
Jim Toomey’s Sherman’s Lagoon for the 5th of October, 2018. And if you’re wondering how an Alexa eavesdropping device is working underwater, go away. The strip’s not for you, and that’s your loss, because it’s nicely low-key weird and teaches me more about ocean biology than I ever imagined I’d know.

Greg Cravens’s The Buckets for the 6th is a riff on the monkeys-at-keyboards joke. Well, what keeps monkeys-at-typewriters from writing interesting things is that they don’t have any selection. They just produce text to no end, in principle. Picking out characters and words that carry narrative is what makes essayists and playwrights. … That said, I think every instructor has faced the essay that is, somehow, worse than gibberish. The process is to try to find anything that could be credited, even if it’s just including at least one of the words from the topic of the essay, and move briskly on.

Eddie: 'You know the old saying about putting an infinite number of monkeys at an infinite number of typewriters, and eventually they'll accidentally write Shakespeare's plays?' Toby: 'I guess.' Eddie: 'My English teacher says that nothing about our class should worry those monkeys ONE BIT!'
Greg Cravens’s The Buckets for the 6th of October, 2018. I’m mostly sure the guy with all the hair is Eddie but, again, character lists. Please.

Larry Wright’s Motley for the 6th is a riff on the idea tips are impossibly complicated to calculate. And that any mathematics might as well be algebra. My question: what the heck calculation is Debbie describing here? There are different ways to find a 15 percent tip. One two-step one is to divide the bill by ten, which is easy and gets you 10 percent. Then divide that by two, which is not-hard, and gets you 5 percent. Add together the 10 percent and 5 percent and you get 15 percent. A one-step method is to just divide by six. This gets you a bit under 17 percent, but that’s close enough. It just requires an ability to divide by six.

Debbie, on the phone: '... multiply by two and move the decimal over one digit ... then divide by four and subtract that answer from the first answer.' Toady: 'Were you helping someone with their algebra?' Debbie: 'No, Dad's at the restaurant and wanted to leave a 15 percent tip.'
Larry Wright’s Motley for the 6th of October, 2018. This strip originally ran in 1987, although I can’t make out when. Also see earlier comments about cast lists; I had to look through about a month’s worth of comics to find both characters’ names here.

There’s other ways to go about it, surely. There are many ways to do any calculation you like. Some of them have the advantages of requiring fewer steps. Some require more steps, but hopefully easier steps. Debbie is, obviously, just describing a nonsensically complicated calculation, to fit the needs of the joke. I’m just trying to think of what a plausible process would lead into the first panel and still get the right answer.

My many Reading the Comics posts are at this link. Essays which mention Sherman’s Lagoon should be at this link. Other essays with The Buckets should appear at this link. And other essays discussing Motley Classics should be here.

Reading the Comics, June 23, 2018: Big Duck Energy Edition


I didn’t have even some good nonsense for this edition’s title and it’s a day late already. And that for only having a couple of comics, most of them reruns. And then this came across my timeline:

Please let it not be a big milkshake duck. I can’t take it if it is.

Larry Wright’s Motley for the 21st uses mathematics as emblem of impossibly complicated stuff to know. I’m interested to see that biochemistry was also called in to represent something that needs incredible brainpower to know things that can be expressed in one panel. Another free little question: what might “2,368 to the sixth power times pi” be an answer to? The obvious answer to me is “what’s the area of a circle of radius 2,368 to the third power”. That seems like a bad quiz-show question to me, though. It tests a legitimate bit of trivia, but the radius is such an ugly number. There are some other obvious questions that might fit, like “what is the circumference of a circle of radius [ or diameter ] of (ugly number here)?” Or “what is the volume of a circle of radius (similarly ugly number here)?” But the radius (or diameter) of those surfaces would have to be really nasty numbers, ones with radicals of 2,368 — itself no charming number — in it.

Debbie, yelling at the TV: 'Hydromononucleatic acid! 2,368 to the sixth power times pi, stupid!' (Walking away, disgusted.) 'I can't believe the questions on these game shows are so easy and no one ever gets them!'
Larry Wright’s Motley rerun for the 21st of June, 2018. It originally ran sometime in 1997.

And “2,368 to the sixth power times pi” is the answer to infinitely many questions. The challenge is finding one that’s plausible as a quiz-show question. That is it should test something that’s reasonable for a lay person to know, and to calculate while on stage, without pen or paper or much time to reflect. Tough set of constraints, especially to get that 2,368 in there. The sixth power isn’t so easy either.

Well, the biochemistry people don’t have an easy time thinking of a problem to match Debbie’s answer either. “Hydro- ” and “mono- ” are plausible enough prefixes, but as far as I know there’s no “nucleatic acid” to have some modified variant. Wright might have been thinking of nucleic acid, but as far as I know there’s no mononucleic acid, much less hydromononucleic acid. But, yes, that’s hardly a strike against the premise of the comic. It’s just nitpicking.

[ During his first day at Math Camp, Jim Smith learns the hard way he's not a numbers person. ] Coach: 'The ANSWER, Mr Smith?' (Smith's head pops open, ejecting a brain, several nuts, and a few screws; he says the null symbol.)
Charlie Pondrebarac’s CowTown rerun for the 22nd of June, 2018. I don’t know when it first ran, but it seems to be older than most of the CowTown reruns offered.

Charlie Pondrebarac’s CowTown for the 22nd is on at least its third appearance since I started reading the comics for the mathematics stuff regularly. I covered it in June 2016 and also in August 2015. This suggests a weird rerun cycle for the comic. Popping out of Jim Smith’s mouth is the null symbol, which represents a set that hasn’t got any elements. That set is known as the null set. Every set, including the null set, contains a null set. This fact makes set theory a good bit easier than it otherwise would be. That’s peculiar, considering that it is literally nothing. But everything one might want to say about “nothing” is peculiar. That doesn’t make it dispensable.

Marlene: 'Timmy's school says that all 7th and 8th graders have to buy a $98 calculator for math this year!' Burl: 'Whatever happened to timesing and minusing in your head?' Dale: 'I remember all we had to get for math was a slide rule for drawing straight lines and a large eraser.' (On the TV is 'The Prices Is Right, Guest Host Stephen Hawking', and they have a videotape of 'A Beautiful Mind'.)
Julie Larson’s Dinette Set rerun for the 22nd of June, 2018. It originally ran the 15th of August, 2007. Don’t worry about what’s on the TV, what’s on the videotape box, or Marlene’s ‘Gladys Kravitz Active Wear’ t-shirt; they’re side jokes, not part of the main punchline of the strip. Ditto the + and – coffee mugs.

Julie Larson’s Dinette Set for the 22nd sees the Penny family’s adults bemoaning the calculator their kid needs for middle school. I admit feeling terror at being expected to buy a hundred-dollar calculator for school. But I also had one (less expensive) when I was in high school. It saves a lot of boring routine work. And it allows for playful discoveries about arithmetic. Some of them are cute trivialities, such as finding the Golden Ratio and similar quirks. And a calculator does do essentially the work that a slide rule might, albeit more quickly and with more digits of precision. It can’t help telling you what to calculate or why, but it can take the burden out of getting the calculation done. Still, a hundred bucks. Wow.

Couple watching a newscaster report: 'Experts are still struggling to explain how, for a few brief moments this year, two plus two equalled five.'
Tony Carrillo’s F Minus for the 23rd of June, 2018. It is not a rerun and first appeared the 23rd of June, 2018, so far as I know.

Tony Carrillo’s F Minus for the 23rd puts out the breaking of a rule of arithmetic as a whimsical, inexplicable event. A moment of two plus two equalling five, whatever it might do for the structure of the universe, would be awfully interesting for the philosophy of mathematics. Given what we ordinarily think we mean by ‘two’ and ‘plus’ and ‘equals’ and ‘five’ that just can’t happen. And what would it mean for two plus to to equal five for a few moments? Mathematicians often think about the weird fact that mathematical structures — crafted from definitions and logic — describe the real world stunningly well. Would this two plus two equalling five be something that was observed in the real world, and checked against definitions that suddenly allowed this? Would this be finding a chain of reasoning that supported saying two plus two equalled five, only to find a few minutes later that a proof everyone was satisfied with was now clearly wrong?

That’s a particularly chilling prospect, if you’re in the right mood. We like to think mathematical proofs are absolute and irrefutable, things which are known to be true regardless of who knows them, or what state they’re in, or anything. And perhaps they are. They seem to come as near as mortals can to seeing Platonic forms. (My understanding is that mathematical constructs are not Platonic forms, at least in Plato’s view of things. But they are closer to being forms than, say, apples put on a table for the counting would be.) But what we actually know is whether we, fallible beings comprised of meat that thinks, are satisfied that we’ve seen a proof. We can be fooled. We can think something is satisfactory because we haven’t noticed an implication that’s obviously wrong or contradictory. Or because we’re tired and are feeling compliant. Or because we ate something that’s distracting us before we fully understand an argument. We may have a good idea of what a satisfactory logical proof would be. But stare at the idea hard enough and we realize we might never actually know one.

If you’d like to see more Reading the Comics posts, you can find them at this link. If you’re interested in the individual comics, here you go. My essays tagged with CowTown are here. Essays tagged Dinette Set are at this link. The essays that mention F Minus since I started adding strip tags are here. And this link holds the Motley comics.

Reading the Comics, June 19, 2018: Don’t Ask About The Hyperbolic Cosine Edition


Although the hyperbolic cosine is interesting and I could go on about it.

Eric the Circle for the 18th of June is a bit of geometric wordplay for the week. A secant is — well, many things. One of the important things is it’s a line that cuts across a circle. It intersects the circle in two points. This is as opposed to a tangent, which touch it in one. Or missing it altogether, which I think hasn’t got any special name. “Secant” also appears as one of the six common trig functions out there.

Small circle: 'Hey, Eric! There's a line on you!' Medium circle: 'Get it off!' Eric, with a line across his side: 'See? Can't!'
Eric the Circle for the 18th of June, 2018. This one was composed by Griffinetsabine. It originally appeared sometime in 2012.

In value the secant of an angle is just the reciprocal of the cosine of that angle. Where the cosine is never smaller than -1 nor larger than 1, the secant is always either greater than 1 or smaller than -1. It’s a useful function to have by name. We can write “the secant of angle θ” as sec(\theta) . The otherwise sensible-looking \cos^{-1}(\theta) is unavailable, because we use that to mean “the angle whose cosine is θ”. We need to express that idea, the “arc-cosine” or “inverse cosine”, quite a bit too. And \cos(\theta)^{-1} would look like we wanted the cosine of one divided by θ. Ultimately, we have a lot of ideas we’d like to write down, and only so many convenient quick shorthand ways to write them. And by using secant as its own function we can let the arc-cosine have a convenient shorthand symbol. These symbols are a point where you see the messy, human, evolutionary nature of mathematical symbols at work.

We can understand the cosine of an angle θ by imagining a right triangle with hypotenuse of length 1. Set that so the hypotenuse makes angle θ with respect to the x-axis. Then the opposite leg of that right triangle will be the cosine of θ away from the origin. The secant, now, that works differently. Again here imagine a right triangle, but this time one of the legs has length 1. And that leg is at an angle θ with respect to the x-axis. Then the far leg of that right triangle is going to cross the x-axis. And it’ll do that at a point that’s the secant of θ away from the origin.

Debbie: 'In this soap opera, Kimberly is trying to hide her past from Renaldo ... who has hired a detective to find out how many times (x) Kimberly has made love to how many lovers (y). ... Who says algebra has no use outside the classroom?'
Larry Wright’s Motley Classics for the 19th of June, 2018. It originally ran sometime in 1997.

Larry Wright’s Motley Classics for the 19th speaks of algebra as the way to explain any sufficiently complicated thing. Algebra’s probably not the right tool to analyze a soap opera, or any drama really. The interactions of characters are probably more a matter for graph theory. That’s the field that studies groups of things and the links between them. Occasionally you’ll see analyses of, say, which characters on some complicated science fiction show spend time with each other and which ones don’t. I’m not aware of any that were done on soap operas proper. I suspect most mathematics-oriented nerds view the soaps as beneath their study. But most soap operas do produce a lot of show to watch, and to summarize; I can’t blame them for taking a smaller, easier-to-summarize data set to study. (Also I’m not sure any of these graphs reveal anything more enlightening than, “Huh, really thought The Doctor met Winston Churchill more often than that”.)

Teacher: 'You two making progress on the math problem?' Nancy: 'We're making progress on *A* math problem.' (Nancy and Esther's paper: 'number of seconds left in school, 24 x 5 x 60 x 60'.)
Olivia Jaimes’s Nancy for the 19th of June, 2018. This one originally appeared in June of 2018.

Olivia Jaimes’s Nancy for the 19th is a joke on getting students motivated to do mathematics. Set a problem whose interest people see and they can do wonderful things.

Circle in the bar, speaking to another circle: 'You wanna get out of here, come back to my place and create a Venn diagram?' ... Squirrel in the corner, adding commentary: 'It'll never work ... they have nothing in common.'
Dave Whamond’s Reality Check for the 19th of June, 2018. Those seem like small drinks for circles that large.

Dave Whamond’s Reality Check for the 19th is our Venn Diagram strip for the week. I say the real punch line is the squirrel’s, though. Properly, yes, the Venn Diagram with the two having nothing in common should still have them overlap in space. There should be a signifier inside that there’s nothing in common, such as the null symbol or an x’d out intersection. But not overlapping at all is so commonly used that it might as well be standard.

Cardinal: 'Whatever you're thinking, don't say it.' Other bird has a thought balloon full of arithmetic expressions.
Teresa Bullitt’s Frog Applause for the 21st of June, 2018. It’s a Dadaist comic strip; embrace the bizarreness.

Teresa Bullitt’s Frog Applause for the 21st uses a thought balloon full of mathematical symbols as icon for far too much deep thinking to understand. I would like to give my opinion about the meaningfulness of the expressions. But they’re too small for me to make out, and GoComics doesn’t allow for zooming in on their comics anymore. I looks like it’s drawn from some real problem, based on the orderliness of it all. But I have no good reason to believe that.


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, Eric the Circle strips are here. Frog Applause comics are on that link. Motley strips are on that link. Nancy comics are on that page. And And Reality Check strips are here.

Reading the Comics, December 30, 2017: Looking To 2018 Edition


The last full week of 2017 was also a slow one for mathematically-themed comic strips. You can tell by how many bits of marginally relevant stuff I include. In this case, it also includes a couple that just mention the current or the upcoming year. So you’ve been warned.

Mac King and Bill King’s Magic in a Minute activity for the 24th is a logic puzzle. I’m not sure there’s deep mathematics to it, but it’s some fun to reason out.

John Graziano’s Ripley’s Believe It Or Not for the 24th mentions the bit of recreational group theory that normal people know, the Rubik’s Cube. The group theory comes in from rotations: you can take rows or columns on the cube and turn them, a quarter or a half or a three-quarters turn. Which rows you turn, and which ways you turn them, form a group. So it’s a toy that inspires deep questions. Who wouldn’t like to know in how few moves a cube could be solved? We know there are at least some puzzles that take 18 moves to solve. (You can calculate the number of different cube arrangements there are, and how many arrangements you could make by shuffling a cube around with 17 moves. There’s more possible arrangements than there are ones you can get to in 17 moves; therefore, there must be at least one arrangement that takes 18 moves to solve.) A 2010 computer-assisted proof by Tomas Rokicki, Herbert Kociemba, Morley Davidson, and John Dethridge showed that at most 20 face turns are needed for every possible cube to be solved. I don’t know if there’s been any success figuring out whether 19 or even 18 is necessarily enough.

Griffith: 'Here we are, Zippy, back in the land of our childhood.' Zippy: 'Are we still in the ninth grade?' Griffith: 'Kind of ... although I still can't remember a thing about algebra.' Zippy: 'So many spitballs and paper airplanes ago!!' Griffith: 'Why did I act up so much in school, Zippy? Was it a Freudian thing?' Zippy: 'It was a cry for kelp.' Griffith: 'Don't you mean a cry for help? I don't think kelp was even a word I knew back in the 50s.' Zippy: 'Seaweed is the fifth dimension!'
Bill Griffith’s Zippy the Pinhead for the 26th of December, 2017. This is not as strongly a memoir or autobiographical strip as Griffith will sometimes do, which is a shame. Those are always captivating. I have fun reading Zippy the Pinhead and understand why people wouldn’t. But the memoir strips I recommend even to people who don’t care for the usual fare.

Bill Griffith’s Zippy the Pinhead for the 26th just mentions algebra as a thing that Griffith can’t really remember, even in one of his frequent nostalgic fugues. I don’t know that Zippy’s line about the fifth dimension is meant to refer to geometry. It might refer to the band, but that would be a bit odd. Yes, I know, Zippy the Pinhead always speaks oddly, but in these nostalgic fugue strips he usually provides some narrative counterpoint.

Larry Wright’s Motley Classics for the 26th originally ran in 1986. I mention this because it makes the odd dialogue of getting “a new math program” a touch less odd. I confess I’m not sure what the kid even got. An educational game? Something for numerical computing? The coal-fired, gear-driven version of Mathematica that existed in the 1980s? It’s a mystery, it is.

Ryan Pagelow’s Buni for the 27th is really a calendar joke. It seems to qualify as an anthropomorphic numerals joke, though. It’s not a rare sentiment either.

Jef Mallett’s Frazz for the 29th is similarly a calendar joke. It does play on 2017 being a prime number, a fact that doesn’t really mean much besides reassuring us that it’s not a leap year. I’m not sure just what’s meant by saying it won’t repeat for another 2017 years, at least that wouldn’t be just as true for (say) 2015 or 2019. But as Frazz points out, we do cling to anything that floats in times like these.

Reading the Comics, May 31, 2017: Feast Week Edition


You know we’re getting near the end of the (United States) school year when Comic Strip Master Command orders everyone to clear out their mathematics jokes. I’m assuming that’s what happened here. Or else a lot of cartoonists had word problems on their minds eight weeks ago. Also eight weeks ago plus whenever they originally drew the comics, for those that are deep in reruns. It was busy enough to split this week’s load into two pieces and might have been worth splitting into three, if I thought I had publishing dates free for all that.

Larry Wright’s Motley Classics for the 28th of May, a rerun from 1989, is a joke about using algebra. Occasionally mathematicians try to use the the ability of people to catch things in midair as evidence of the sorts of differential equations solution that we all can do, if imperfectly, in our heads. But I’m not aware of evidence that anyone does anything that sophisticated. I would be stunned if we didn’t really work by a process of making a guess of where the thing should be and refining it as time allows, with experience helping us make better guesses. There’s good stuff to learn in modeling how to catch stuff, though.

Michael Jantze’s The Norm Classics rerun for the 28th opines about why in algebra you had to not just have an answer but explain why that was the answer. I suppose mathematicians get trained to stop thinking about individual problems and instead look to classes of problems. Is it possible to work out a scheme that works for many cases instead of one? If it isn’t, can we at least say something interesting about why it’s not? And perhaps that’s part of what makes algebra classes hard. To think about a collection of things is usually harder than to think about one, and maybe instructors aren’t always clear about how to turn the specific into the general.

Also I want to say some very good words about Jantze’s graphical design. The mock textbook cover for the title panel on the left is so spot-on for a particular era in mathematics textbooks it’s uncanny. The all-caps Helvetica, the use of two slightly different tans, the minimalist cover art … I know shelves stuffed full in the university mathematics library where every book looks like that. Plus, “[Mathematics Thing] And Their Applications” is one of the roughly four standard approved mathematics book titles. He paid good attention to his references.

Gary Wise and Lance Aldrich’s Real Life Adventures for the 28th deploys a big old whiteboard full of equations for the “secret” of the universe. This makes a neat change from finding the “meaning” of the universe, or of life. The equations themselves look mostly like gibberish to me, but Wise and Aldrich make good uses of their symbols. The symbol \vec{B} , a vector-valued quantity named B, turns up a lot. This symbol we often use to represent magnetic flux. The B without a little arrow above it would represent the intensity of the magnetic field. Similarly an \vec{H} turns up. This we often use for magnetic field strength. While I didn’t spot a \vec{E} — electric field — which would be the natural partner to all this, there are plenty of bare E symbols. Those would represent electric potential. And many of the other symbols are what would naturally turn up if you were trying to model how something is tossed around by a magnetic field. Q, for example, is often the electric charge. ω is a common symbol for how fast an electromagnetic wave oscillates. (It’s not the frequency, but it’s related to the frequency.) The uses of symbols is consistent enough, in fact, I wonder if Wise and Aldrich did use a legitimate sprawl of equations and I’m missing the referenced problem.

John Graziano’s Ripley’s Believe It Or Not for the 28th mentions how many symbols are needed to write out the numbers from 1 to 100. Is this properly mathematics? … Oh, who knows. It’s just neat to know.

Mark O’Hare’s Citizen Dog rerun for the 29th has the dog Fergus struggle against a word problem. Ordinary setup and everything, but I love the way O’Hare draws Fergus in that outfit and thinking hard.

The Eric the Circle rerun for the 29th by ACE10203040 is a mistimed Pi Day joke.

Bill Amend’s FoxTrot Classicfor the 31st, a rerun from the 7th of June, 2006, shows the conflation of “genius” and “good at mathematics” in everyday use. Amend has picked a quixotic but in-character thing for Jason Fox to try doing. Euclid’s Fifth Postulate is one of the classic obsessions of mathematicians throughout history. Euclid admitted the thing — a confusing-reading mess of propositions — as a postulate because … well, there’s interesting geometry you can’t do without it, and there doesn’t seem any way to prove it from the rest of his geometric postulates. So it must be assumed to be true.

There isn’t a way to prove it from the rest of the geometric postulates, but it took mathematicians over two thousand years of work at that to be convinced of the fact. But I know I went through a time of wanting to try finding a proof myself. It was a mercifully short-lived time that ended in my humbly understanding that as smart as I figured I was, I wasn’t that smart. We can suppose Euclid’s Fifth Postulate to be false and get interesting geometries out of that, particularly the geometries of the surface of the sphere, and the geometry of general relativity. Jason will surely sometime learn.