Independent Learning

I’ve been having fun embarking on a new research project this semester. This requires a lot of reading and hunting down the appropriate resources. Sometimes I’m looking for a brief introductory overview of a particular concept or approach; at other times I’m looking for a specific application or methodology. Finding the right materials at the right level, so I can get the most out of it, can be challenging. While the process is occasionally frustrating, I do enjoy the scent and the hunt to learn something new. I’m also reasonably efficient and well-practiced in separating the wheat from the chaff in the Internet era.

How do novice students try to learn something new? Before the internet, you might go to the library and look for (what you hope is) the appropriate book or encyclopedia. Or you might try to find an expert in the area – this could be a teacher/professor or some other practitioner. You are likely to trust the library book or the area expert. Information is scarce, and for it to get into an encyclopedia or an expert’s brain-schema, it is likely significant resources were expended to do so. The information is probably of ‘good’ quality because it has been filtered by the appropriate gatekeepers.

In the Wild Wild Web (WWW) of information abundance, the problem is wading through the chaff to get to the needle in the haystack. How does one filter through that information? With modern search engines, an Artificial Intelligence (A.I.) bot sorts or ranks the information according to some algorithm. And if you so happened to find what you wanted, the ‘helpful’ bot might even suggest or recommend what you might look into next. For example, “folks like you who read X also read Y.” The algorithm is based on some assumptions, and further interactions between the user and the algorithm refines it – for better or for worse. Algorithms can also be ‘gamed’ by users.

All this made me think about the push towards online ‘personalized’ learning. I’ve looked at some of these adaptive-learning systems, which guide a student through learning a particular topic. To find out where the student is at, questions are posed. Based on the students correct or incorrect or half-correct answers, an algorithm ‘decides’ the next item in the sequence that the student should tackle. Presumably this is based on some logical pedagogical system. Maybe we should call this pedalogic. (Hah! I invented another new word.) The system filters the student through twists and turns in its database, supposedly to provide the optimum pathway that meets the personalized learning needs of that student. At least that’s what is advertised.

In these adaptive-learning systems, the components of the system have already been vetted, presumably by pedalogical experts (practicing instructors working with educational technologists). While this may pull from WWW, it has been pre-curated by humans. (Post-curation, pathways can be determined by algorithms and user statistics.) Could a similar system work for an independent learner navigating with WWW as an information source? Let’s call it GooglExpert – the adaptive-learning powerful A.I. searchbot. GooglExpert may ask you a few questions during the process to narrow the search scope and collect information to further populate its search database for future users. In this way, it curates the parts of WWW most useful or reliable at the level appropriate to the user. A bunch of data down the road could lead to a lucrative paywalled-garden within the WWW. GooglExpert might even hire expert practitioners to contribute.

If high quality learning requires high quality curation, who or what is best at it? A single novice learner would not be able to separate the wheat from the chaff, but a crowd-sourced group of relative novices might. Would an expert actually be needed? Maybe at some stages. I guess I’m asking myself what relevance I would have to the life of a student in an age where independent learning could take place through GooglExpert Garden. How important is the relationship between humans to the learning process? Maybe it’s different at different learning stages. I could probably teach myself quite a bit of new chemistry, but wouldn’t it be so much richer if I learned it directly from a human expert in the field? Perhaps it’s because I can’t imagine a versatile enough A.I.-bot, but maybe it’s just that I lack imagination.

In the meantime, more exciting independent learning awaits!

Happily Ever After

I hadn’t planned on watching Season 6 of Once Upon A Time, after the incoherent mess that was Season 5. But I spotted the DVD set while browsing in my local branch library, and decided to try a few episodes. One of my former students had mentioned a year ago that Season 6 was looking better than Season 5 (thanks to the return of the Evil Queen). I was a bit confused in the first few episodes, not remembering most of the mess of the previous season, but it looked promising from the storytelling point of view.

But then things start to fall apart.

Spoiler alert!

More new characters are introduced, and some of them were potentially interesting. But old characters are also revived, and this is simply TOO MANY characters! The main cast have settled into one-dimensional caricatures. The Evil Queen and Gold/Rumpelstiltskin continue to be interesting, but the rest of the characters seem ‘wooden’. They’re mainly foils responding to each other to drive the narrative forward – except that the narrative itself is a mess. Resolution of the storylines fall into two main categories: (1) artificially forced with high speed, or (2) incoherently dragged out and messy.

I happen to be re-reading Mind of the Maker by Dorothy Sayers, and her description of the ideal interplay between the writer and the character of the stories is short-circuited in many of the later season episodes in Once Upon A Time. The story just feels shallow; as if someone took the Shears (Scissors) of Destiny and cut off the appropriate story resolutions. It’s too bad because the Shears of Destiny make their appearance in several episodes, and had the potential to be a very interesting magical object. This is coupled with the early theme of characters crashing into Storybrooke from the Land of Untold Stories – folks trying to escape their fate and find a new destiny. I had glimpses of what might have been interesting story arcs, only to be bewildered as threads were dropped or cut off prematurely. If this was meant to be an underlying philosophical current to the story, it failed spectacularly.

Each subsequent season requires an even badder baddie. The Black Fairy however is a rather one-dimensional villain – uninteresting for the most part. Even her back story felt forced, although perhaps it makes a good case for why you shouldn’t ask too many questions about your future destiny. Prediction is such a messy science. There is a further exploration of the blurring of lines between Heroes and Villains, and Season 6 does a reasonably good job here with several sets of characters. The part where the town comes together to share an evil curse so as to dilute its effects was well done. The seemingly obligatory musical episode was overall amusing, and while a bit clumsy, it adequately fit into the overall narrative arc. The setting of the Final Battle being about What To Believe, mirroring the opening of Season 1, was overall good, although the final resolution still felt forced.

One thing I liked about Season 6 was that in some instances the characters, now seasoned in the unforeseen effects of magic, try to think a bit more carefully around the dictum “all magic comes with a price”. This leads to a clever use of making wishes of the Genie of the Lamp, and leads to a wish-dream world that overall seemed to hang together quite well. Yes, Aladdin, Jafar and Princess Jasmine make their appearance. In particular, Aladdin’s ‘savior’ character and the Shears of Destiny, allow for the exploration of some interesting ideas. Except for the Genie’s Lamp, there wasn’t much of an exploration of magic in an interesting way, except maybe for the clumsy approaches to stopping the magic of another. Apparently dexterity and an appropriate wristband work well and often.

I am pleased that the season came to an end with a version of “And They Lived Happily Ever After”. While there were allusions to the-next-generation, I have no plans on watching it. The current cast gets to the end of their fairy tale in a fitting ending even though the journey was convoluted.

P.S. Here are my previous musings of Seasons 1-3 and Season 4. I didn't bother writing about Season 5.

P.P.S. The card game Once Upon A Time, unrelated to the TV series, is actually quite good.

Seeing the Unseen: Spineless Version

Jellyfish are fascinating. I hadn’t realized as much until my eyes were opened reading Spineless by Juli Berwald.  Part-memoir, yet chockfull of scientific facts, Berwald takes you around the world in her quest to consume all things jellyfish. Yes, she even decides she has to try cooking and eating some! The subtitle of the book is The Science of Jellyfish and the Art of Growing a Backbone. I found it even harder to put down then the excellent I Contain Multitudes by Ed Yong, and read multiple chapters in a single sitting. I will just highlight one of them.

Chapter 7 is titled Seeing What’s Not There. Having pondered Invisibility Rings and Making Visible the Invisible in chemistry, this chapter was particularly fascinating. Yes, it’s about jellyfish transparency – but there are many other equally fascinating denizens of the deep highlighted by Berwald. The tale of transparency begins with her interviewing the jellyfish scientist, Richard Harbison, asking him why so many jellyfish are transparent. His response: “The question is, why isn’t everything transparent?”

Berwald ponders this question and writes: “In the ocean, with nothing to hide behind and nothing to blend into, being opaque puts you at risk of being seen. Being seen means being eaten. Invisibility is also an advantage if you are a predator. Prey are more likely to steer clear if they can see you. Prey might just stumble into your grasp if they can’t. Transparency is an underwater invisibility cloak; the ultimate disguise.”

Posing Harbison’s question to another scientist, Sonke Johnson, comes the reply: “because it’s hard.” A surface-dwelling creature only needs to blend into its surroundings; a “surface paint job” might suffice. But for an ocean roamer, one needs to do much better. Berwald writes: “Some animals do this by being extraordinarily thin. Light passes through such animals so easily that it encounters almost nothing to scatter it. One supermodel of transparency is a comb jelly called the Venus girdle, which is less than an inch thick, but can stretch a yard and a half in length. The animal’s svelteness decreases scattering so much that in photographs it looks like just a few white lines dashed off by a sketch artist.”

Berwald anticipates the reader’s next question. “But many jellyfish aren’t flat; they are bulbous round things.” Having previously discussed jellyfish locomotion and buoyancy powered by its amazing mesoglea, it turns out that “watery mesoglea is a brilliant solution to being transparent… [because] light passes through the mesoglea nearly the same way it passes through the ocean.” Berwald just has a way with words. “Jellyfish are physically fat and optically skinny.” But there’s more. “And being physically rotund matters a lot more in the open ocean, where there’s nowhere to hide, because even the best invisibility cloak isn’t perfect… [If] spotted by a predator, it’s always better to have heft on its side. No one wants to tangle with a big dude. The mesoglea allows a thin jellyfish to masquerade as a jumbo version of itself, and it does so on the cheap… jellyfish get a lot of heft, not for free but at a significant metabolic discount.”

I’m essentially quoting Berwald to give you a flavor of her engaging prose, and also because I would do a lot worse trying to capture what she writes in my own clumsy narrative. You’ll have to read the book (and it is a delight!) if you want to know why the blood belly comb jelly has a currant-colored stomach. I also learned that in Spanish, jellyfish is medusa. And yes, Berwald appropriately weaves in the Greek mythology in her book. Jellyfish might hold a clue to immortality. And their famed barbs are more sophisticated than I could have ever imagined. (Below is the Australian Box Jellyfish, picture taken from World Atlas.)

As for humans living on a terrestrial surface terraformed into urban sprawls, a camouflage cloak would have to be extremely sophisticated to mask the presence of its wearer. A true cloak of invisibility, like the one handed down to Harry Potter from his ancestors, would be a marvel indeed. The best we can do with our modern optics and sensors is probably an invisibility shield. Several variations have shown up in movies featuring hi-tech gadgets. But in the realm of the merpeople, a hi-tech invisibility wetsuit would be within reach. Then again, it depends on who’s looking and how they are looking. Not every creature exploits the visual, especially if there’s little light in the depths.

In any case, I am looking forward to my next visit to an aquarium. Having read Berwald’s fantastic book, I will never look at jellyfish the same way again. I’ll be spending time looking a lot closer and harder, to see what I had not seen before!

Managing Energy Levels

The drawback with a long winter break is getting back into the swing of things once the new semester begins. For me, this is about managing energy levels. While I came into work on a regular schedule several weeks before the start of classes, much of my time was spent sitting in my office in front of my computer. I was either preparing for classes, reading or writing. There were hardly any meetings to attend. Every semester, my teaching schedule is a little different. This semester I’m teaching on MWF mornings (starting at 8am). That’s also when I hold chunks of my office hours. In the (MWF) afternoons I have scheduled meetings with my research students.

I made it through my first full week of classes (last week). By mid-afternoon on MWF, I felt drained of energy. Students have been coming into office hours to get help on homework even in the first week (good for them!) so I’m basically engaged with students for a chunk of the day from 7:45am when I start chatting with the first few folks walking into class, until about 2:30pm. What seems to work is to have a good breakfast, teach my first class, then have a snack, before students start showing up for office hours. (This morning, they showed up before I had finished my oat bar.) Then I teach my next class, have lunch, and meet my research students. My students would characterize me as enthusiastic in class; but this means I expend a lot of energy in class discussions. Asking and answering questions during office hours, further drains my energy.

The good news is that my Tue/Thu schedule is much lighter. I have a couple of administrative meetings on Tue followed by another office hour block. I’ve purposefully kept my Thu free of office hours, although if a student finds me and needs help, I’m generally willing to oblige. (That’s the culture in my department, and I enjoy helping students learn chemistry, so I welcome them.) My goal is to spend chunks of Tue/Thu thinking about research, scholarship and creative activity. At least that’s the plan this semester, and so far it seems to have worked well in Week #1. Today, I was still feeling tired by mid-afternoon, but I feel a little less drained compared to last week. So I think I’m doing a better job managing my energy levels, i.e., I’m getting used to my new schedule.

As I was pondering how to manage my energy levels this past week, I was reminded of one of my research projects – exploring how a proto-metabolic system might arise from a bunch of chemical substances. This is the ‘metabolism-first’ approach to the origin of life, i.e., managing energy flow into the system to create dynamic dissipative structures (and by structures I mean networks of molecules) that ‘take advantage’ of non-equilibrium thermodynamics. It’s a fine line, though. Too much energy flux leads to a variety of unproductive side reactions that consume metabolic molecules without regenerating them quickly enough. But too little energy makes it challenging to maintain the system away from equilibrium. The molecules that make up a proto-metabolic cycle (or hypercycle, or even systems of hypercycles) are likely sensitive to changes in flux. Optimizing such a system requires exquisite managing of the energy levels of the individual molecules that are consumed and regenerated in these cycles. By that I mean, the molecules and chemical reactions involved have been honed over time by chemical evolution, to be dissipative structures in their given chemical environments.

In my second semester General Chemistry classes this semester, the first third of class is on chemical thermodynamics. This is followed by a short section on chemical kinetics, taking us to Spring Break! After we go through the basics of kinetics, my plan is to spend one class session talking about how thermodynamics and kinetics relate to the chemical origins of life. There’s a video I have my students watch before class so that they understand the difference between thermodynamic and kinetic control. (The key figure is shown below.) But this example is a very simple case – and one that will not generate a metabolic cycle. But if you imagined a cascade of interconverting structures with just the right energies and barriers, and the appropriate energy flow, you could create stable cycles – but they would be dynamically stable.

When the semester is in session, my energy and activity follows somewhat of a weekly cycle. There are energy highs and lows, and I need certain rest periods and energy boosters to get me through the turnovers. There are inputs and outputs, and the energy flux in my classrooms may vary depending on students’ participation in class discussions. Exams and events (Spring Break!) will shift these fluxes temporarily until the hum of the regular cycle picks up again. Efficiencies change when adapting to these variables. That’s what I’m trying to do in Week #2 – to adapt my energy levels so I am operating efficiently and dissipating my energy at a more sustainable rate, as I cycle through the semester.

The Measure of a Student

I finished reading Cathy Davidson’s latest book, The New Education, subtitled: How to revolutionize the university to prepare students for a world in flux. It is the latest in a series of many articles, books, and presentations, made by pundits bemoaning the state of higher education. Having read much in this area already, I did not learn anything new here, but Davidson’s book collects the main threads of the web and delivers them with a clear narrative. Like many other popular pieces, the points being made are illustrated by personal stories of individuals, some data analysis, and a splash of history for narrative arc.

In today’s post, I will concentrate on Chapter 7 (“The Measure of a Student”) because it’s something I’ve been thinking hard about this past month. In particular, I’m motivated (again) to de-emphasize grades and exams, and to find alternative assignments and assessments in my introductory general chemistry courses. My hope is to find that happy medium between depth-rigor of knowledge (students must know the basics!) and creative application of that knowledge (students acquire relevant skills that will serve them both present and future).

“The Measure of a Student” is about assignments and assessments. Davidson’s anecdotal human interest story is an adjunct math professor at UC-Berkeley, who seems to be a fantastic teacher, who loses his job ostensibly because of his unconventional approach. The professor is quoted: “What does it mean to adhere to department norms if one has the highest student evaluation scores in the department, students performing statistically better in subsequent courses, and faculty universally reporting ‘extraordinary skills at lecturing, presentation, and engaging students’?... In a nutshell: stop making us look bad. If you don’t, we’ll fire you.” (His students also apparently “scored just as high or higher” on standardized departmental final exams.

The splash of history will be familiar to those who have looked into the history of grades. Mount Holyoke College is credited as the first institution to systematically create and implement a letter-grade system. Originally A, B, C, D and E, with A being the top grade (similar to classifying egg-size back then, get your “Grade A” eggs!), there was a controversy over the E grade. Apparently there was a fear that students would attempt to misrepresent E to future employers as “Excellent”, or in Hogwarts parlance “Exceeds Expectations”. (I suppose it could also be “Egghead”.) The E was changed to the dreaded F, derived from “the old Anglo-Norman failer, meaning nullification, nonoccurrence, or failure.” Use of the F spread to other institutions, but in addition, an agriculture professor at the University of Illinois introduced grades to the meatpacking industry.

Meatpackers, skeptical that a single letter grade could represent “something as complex as the quality of sirloin or chuck… insisted that, along with the grade, the written comments of the meat inspector to be tied to each and every piece of meat.” We no longer seem to have that metadata, and the USDA now uses words rather than letters. Prime. Choice. Select. No one is going to buy B grade meat, or anything lower, at least in today’s society. It’s no wonder that for many of our students today, getting a B is a tragedy. Anything less than A seems like a failure. I hope we don’t go the route of the Australian guide to kobe beef – slicing up the A’s into finer categories.

It’s not easy to buck the trend. Except for trend-buckers such as Hampshire or Reed College, most of us and our institutions caught in a vast system, made more acute by technology. At the end of the book, Davidson has a section addressed to students: Ten Tips for Getting the Most out of Your College Experience. #10 reads: When it’s time to submit an actual, professional resume, remember your first reader might be an algorithm. Sadly, this is likely to be increasingly true. I do like some of Davidson’s other tips including #2 Mitigate risk while taking risk. My favorite (and clearly I’m biased) is #3 Find a great prof and take advantage of all they can offer. In particular: “Great profs don’t just lecture well – they challenge you to think in new ways about new things. They don’t give answers; they ask deep questions. Visit their office hours…”

Davidson, like many others before her, argues strongly against standardized exams, with standardized questions, and standardized answers. She also argues that these do not lead to future palpable impact, and that we should be preparing our students differently. Exams are proxies for what the student “knows”, but is that enough? And are they even good proxies? (I suppose it depends on how the exam is written and how you prepare the student up to that point.) As I look to revamping my introductory chemistry courses, this time around, I’ve decided to strongly take student input into account. I’ve invited a couple of former students who were in my general chemistry course last year and my research methods course last semester (where we had a creativity thread!) to help me redesign assessments and assignments that are more open-ended and creative, without sacrificing the things the students must learn the ‘old-school’ way. I’m trying to refrain from imposing my ideas early on and allow wild ideas to flow back and forth in our group discussions. I’m already excited for next semester! In the meantime, I need to maintain my focus on trying to be an excellent teacher in my classes this semester. We’ve only just started, and setting the right tone and environment is crucial.

Order from Chaos: OoL Version

How did life begin?

Does the Origin of Life (OoL) exemplify order from chaos?

Ancient cosmologies suggest that this is so. In the ancient Egyptian cosmos, the earth and sky are separated from chaos, thanks to gods and goddesses. The Bible book of Genesis begins the creation story with turning chaos into order, by importantly separating the different waters. (Seas were considered ‘chaotic’.) The Babylonian Enuma Elish begins with two god-oceans, Apsu and Tiamat, with conflict leading to creation of the heavens and the earth. Old maps would indicate uncharted waters where chaos reigns. There be dragons. Or Leviathans.

Being unable to experimentally test any of the ancient cosmologies, today’s priesthood of scientists tries to narrow the question. How did seemingly more complex ‘living’ things arise from seemingly simpler things? Inherent in this narrower question are two assumptions: (1) that there is some correlation between life and complexity, and (2) that there is directionality from the simpler to the more complex.

Modern-day research into the chemical origins of life gained momentum starting with the classic Miller experiment (1953). Simple chemicals (methane, ammonia, hydrogen, water) were mixed, and after sparking the mixture with an energy source, lo and behold, seven days later, more complex molecules appear! These include some of the most common amino acids – the building blocks of proteins in all systems we characterize as ‘alive’. In the last sixty years, scientists have successfully synthesized practically all the ‘building block’ molecules of life from simpler substances. Progress has also been made in connecting the building blocks to make larger and more complex systems. Simple to complex – possibly one measure of life increasing from low to higher ‘order’ and conjures up the ‘great chain of being’. (Picture below is one of many from the link.)

Synthesizing more complex ‘life’-like molecules revealed another enigma. These chemical reactions made a very, very, very wide range of molecules, many of which resemble the molecules of life; close cousins you might call them. Extant life only uses a tiny subset of these molecules and it is unclear how or why. This conundrum is known as the Prebiotic Chemist’s Nightmare. It is an embarrassment of riches in the form of a gooey brown or black tar. Somehow selectivity must be involved. Scientists are working hard to uncover the rules that govern such selectivity, or failing that, a plausible contingent pathway that may have led to the particular choices we see in life today. By ‘choosing’ just a few options among the plethora available, life brings some order to the chaos. The narrowing of choices may be one measure of order. If anything and everything goes – well, that’s just chaos.

One area where scientists have made good research progress is in making proto-cells. These cells do not contain everything that is needed for life, but they can self-assemble, divide, and perform chemical reactions. Most origin-of-life scientists agree that encapsulation, forming a boundary that keeps some chemicals inside, and other stuff outside, is an early crucial feature of proto-life. It promotes catalysis, prevents important molecules from being diluted away, and provides a basis for growth, inheritance and evolution. Boundaries. Maybe that’s what brings order to chaos. In a sense, this echoes the ancient cosmologists. By separating the realms, the chaotic ill-defined ‘void’ or sea is brought to order.

The restlessness of the sea – water in its liquid state – brings opportunities for life to flourish. All living cells contain water. The liquid juice may be gooey and viscous, but fluidity allows dynamic motion while preserving structural integrity. This is what makes the liquid phase much more interesting than the solid or the gas phase. Liquids, particularly gooey ones packed with solutes, are also much more difficult to describe in a mathematical model. The behavior of solids and gases turn out to be much easier to model and make predictions about subsequent behavior, i.e., their evolution is perhaps much less interesting. We can in fact describe gases in an orderly way, because after all the word ‘gas’ comes from chaos.

Liquids, on the other hand, operate at the edge of chaos. This is also how most of us in the field would describe life and living systems; they operate at the edge of chaos. Things could turn catastrophic and lead to widespread death, and it all balances on a knife’s edge. For example, DNA error correction mechanisms operate at this very edge, finely balanced with mutation rates and what is barely needed for the next generation to function. If the ability to evolve and diversify is one feature of life, it must operate at the edge of chaos.

So how did life begin? We still don’t know the answer, and it seems that some semblance of order is needed amidst the chaos, be it complexity, selectivity, or defining boundaries. But chaos seems to also play an important role in the richness of life. Perhaps the ancient cosmologists were on to something that we modern day scientists are just starting to glimpse.

Order From Chaos: MM version

A guest post from an avid reader of murder-mystery books. My companion “Order from chaos” on the origin-of-life will be coming up next.

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Order from chaos: The appeal of the murder mystery

Why murder? From the Golden Age mysteries of Agatha Christie, Ngaio Marsh and Josephine Tey, to the ubiquitous police procedurals on TV today, what is the fascination with homicide investigations? Public libraries today have whole sections just for “Mystery” (most of which are murders). Isn’t the name of the sub-genre of “cozy mysteries” (most of which are murders) an oxymoron?

One possible answer is that murder comes with an air of finality, a kind of certainty in an uncertain world. A tragedy has occurred; a person’s life has been ended. And yet, in the investigation, life goes on. Not for the victim, maybe, but for those around them. There is life after death. The detective and his team encounter a mass of relevant and irrelevant information. They tease out the complex web of relationships. Slowly, they sift through the debris of life and personalities, and zero in on facts. They bring these facts in line and use them to establish means, motive and opportunity. The murder investigation makes meaning out of the chaos of life and death—it is an oasis of order in a disorderly world.

That is why it is strangely comforting to observe the tidy trail of interviews of Hercule Poirot, to follow the measured progress of Inspector Parker or Alleyn or Grant or Lewis, to bask in the California sunshine with the team from The Mentalist. All detectives, like Poirot, rely on the “little grey cells”. But whether it is Father Brown, who emphasizes the psychology of the individual, or Chief Inspector Gamache of Quebec, who believes in the emotions, or Lord Peter Wimsey and Harriet Vane, who dismiss motive and insist on means—“when you know how, you know who” (see “Busman’s Honeymoon”), both the homicide detective and the private agent of inquiry go about their work with reason, method, and deliberation. They ask questions, and they reflect. They (or their underlings) follow leads, take notes, write summaries. They review the evidence. All persons are categorized, all events gathered into a timeline. Everyone is accounted for, everything has its proper place.

The thing that cannot be accounted for, the one who does not fit—that is the clue that breaks the case open. Inconsistency is what the bloodhounds are looking for. That is why the police collect (and try to break) alibis. That is how Father Brown cuts through conundrums. A murder investigation is eminently rational, even if the crime itself is not. “When you have eliminated the impossible, whatever remains, however improbable, must be the truth,” Holmes tells Watson.   

In the murder mystery, all murders are solved, even if not all killers are brought to justice. Donna Leon’s Brunetti often finds that although he may have found the proximate cause—the identity of the killer or the truth behind the murder, the moving force or unseen hand remains elusive, unpunished. The problem of evil and corruption is too pervasive. Still, by the end of the investigation, all motives and movements, jumbled truths, half-truths, and lies, have been sorted out. People’s lives have been put under a microscope, turned inside out—there is no privacy in a murder investigation, says P.D. James’ Adam Dalgliesh—and made sense of.  

By the end, we know who is guilty and who is innocent (and of what); why he said this or she said that; how someone panicked, who covered for whom, which parts were totally irrelevant. Out of the messiness of daily life, all the comings and goings have been filed, sorted, discarded—everyone’s character has been revealed, the victim has been brought back to life and laid to rest; everything now makes sense. We have lived, for awhile, in an orderly world. We have looked at the consequences of violent death (cf. newer series like Broadchurch and The Killing) and survived. Life is a puzzle, but we have the means to solve it. That is the power of the murder mystery—all wrapped up in a neat package, ready to be examined at your leisure. A way to spend some time in a world that, for once, makes sense.