The Work of Dr. Wesley Harris

Dr. Wesley Harris was one of the first African-American students accepted to UVA and the first African-American member of the Jefferson Literary and Debating Society, a club I joined during my time in grad school. For Black History Month, I wanted to look up his work and share it with other people. I said this would be the engineering equivalent of our law students looking up the case history of our first woman member, Barbara Lynn.

Wesley Harris sitting behind a microphone

Wesley Harris was born in Richmond in 1941, and was interested in flight from a young age. As a child, he would make model airplanes out of balsa wood or plastic, and he even made self-powered ones that used rubber bands. By fourth grade, he wanted to be a test pilot. Harris was one of seven Black students first admitted to the University of Virginia in 1960. The students were only allowed to study within the School of Engineering and Applied Science. A friend who knew the history told me this was because “practical” engineering work was considered the only suitable field of study for these seven students, and they were barred from the “intellectual” College of Arts and Sciences and other units.

Harris invited Martin Luther King Jr. to speak at UVA in 1963, which was considered momentous in the history of UVA and, to some, revitalized King’s momentum in the Birmingham campaign. The administration at the time did not really acknowledge the King visit and the then-president of the university did not meet with him. While walking with King and the professor hosting him, Harris heard a loud noise and tried to protect King thinking it was a gun shot, but it turned out to be car engine blowing out. Harris was inducted into Tau Beta Pi, the engineering honor society, and for his senior year (or if you insist on the UVA terminology, “fourth year”) was accepted to live on the Lawn of the Academical Village, the original part of the university grounds designed by Thomas Jefferson. For non-UVA people, living on the Lawn is a BIG deal and basically like an honor society of its own. Lots of people believe Harris was the first Black student to live on the Lawn, but Harris will be one of the first to say he was actually the second and point out that he came after Leroy Willis. Harris graduated with honors in aeronautical engineering in 1964.

Harris went on to graduate school at Princeton, where he earned a master’s and PhD in aerospace and mechanical sciences. He then went back to UVA as a professor, becoming the first African-American professor in the engineering school and the first to receive tenure at UVA. He taught at UVA for two years before moving to Southern University, a historically Black university in Louisiana, and then took a visiting professor position at MIT before joining the aeronautics and astronautics department there full-time.

Dr. Harris’ early research focused on fluid dynamics and the acoustic properties of rotor blades (like helicopter blades). He studied objects moving close to or above the speed of sound and the noise they generate. This is important because excessive noise represents lost efficiency in a rotor. Additionally, if high-speed supersonic/hypersonic vehicles are to become a reality, we need to reduce the noise they generate from shock waves (a common complaint about the Concorde when it used to fly). Dr. Harris worked to replace “semi-empirical” (a term in engineering that often means we’ve found a way to mathematically describe something, but don’t understand the principles well) models of shock waves from helicopter rotors with more theoretically-backed analytical models. This work on helicopters and high-speed air flows earned him a spot as a fellow of the American Institute for Aeronautics and Astronautics (AIAA). His work and service have also made him a fellow of the National Academy of Engineering. For professional researchers, becoming a fellow of a scientific society is basically the grown-up version of being in a high school or college honor society, and being a fellow of one of the National Academies is one of the highest honors you can get in STEM fields.

Since around 2000, Dr. Harris has studied the fluid dynamics of sickle cell disease. If you’re aware of sickle cell disease, you may generally think of the problem being the defective hemoglobin sickle cells have that is less efficient at carrying oxygen. However, another problem is that the strange shape of sickle cells can cause them to get stuck and accumulate in smaller blood vessels, causing a “sickle cell crisis”. Dr. Harris and his students have been developing models to better predict what causes the onset of crises, looking at both the movement of the blood cells and the chemical diffusion of oxygen during a crisis.

Like many other STEM professors who reach a certain age, Dr. Harris has also been very active in understanding and improving engineering education. In 1996, he wrote a paper for AIAA titled “Will the last aeronautical engineering turn out the light?”, looking at the evolution of aeronautical engineering curricula since WWII. In the article, he raises a concern that that newer changes are de-emphasizing engineering science fundamentals to focus on specific technology systems companies want students to know, but could quickly become outdated over the course of an engineer’s career.

in 2012, Dr. Harris co-authored “Opportunities and Challenges in Corrosion Education” with the current chair of the materials science department at UVA as part of a program for the National Research Council. The paper argued that knowledge of corrosion is informally handled in many engineering programs and often non-existent. At the undergraduate level, most schools without research faculty do not teach corrosion concepts, and if they do, the topic is rarely covered in required classes and is only given a lecture or two’s worth of time. (UVA gets a positive shout out here for the MSE department’s class on fuel cells, batteries, and corrosion that links them all through a focus on basic electrochemistry.) At the graduate level, the report expressed concern that research funding into corrosion is declining. I think this paper is particularly important in that it partially predicts the conversation developing in engineering circles after the Flint water crisis. Although even after reading through dozens of articles and engineering memos by contractors, I still don’t entirely understand the technical conversations that went on, I think the report’s fear that corrosion engineering wasn’t taught conceptually came into play here. If you were just going off something like a corrosion chart, you might not understand why highly chlorinated water poses a corrosion risk otherwise stable metals and alloys.

Finally, Dr. Harris has been incredibly active in serving the broader scientific and engineering communities. He was dean of the School of Engineering at the University Connecticut from 1985 to 1990 and a member of Princeton’s Board of Trustees from  2001 to 2005.  He chaired the National Research Council’s Committee to Assess NASA’s Aeronautic Flight Research capabilities, which concluded that NASA should enhance its research into Earth-based flight in the 2010s in a way to enable a boom similar to how NASA’s work in the 90s enabled modern commercial and military use of drones. In particular, the committee said NASA should test more environmentally friendly aircraft and supersonic passenger aircraft to spur on those fields. At the National Academy of Engineering, Dr. Harris serves on the Committee on Grand Challenges for Engineering, defining important issues for engineering to solve. It seems incredibly appropriate that this trailblazing figure for engineering and society in the 20th century now works to identify the challenges we will face in the 21st century. And of course, this was only a summary of what Dr. Harris has done. If you want to see more, you can start at his MIT faculty page.

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What to do if you’re inside a scientific revolution

A LesserWrong user (LesserWrong-er?) has a thought-provoking post on The Copernican Revolution from the Inside, with two questions in mind: (1) if you lived in 17th century Europe, would you have accepted heliocentrism on an epistemic level, and (2) how do you become the kind of person who would say yes to question 1? It’s interesting in the sense the often-asked question of  “What would you be doing during the Civil Rights Movement/Holocaust/Other Time of Great Societal Change” is, in that most people realize they probably would not be a great crusader against the norm of another time. But as someone in Charlottesville in the year 2017, asking about what you’d be doing in scientific arguments is less terrifying relevant than asking people about how they’d deal with Nazism, so we’ll just focus on that.

Cover of Kuhn's The Structure of Scientific Revolutions showing a whirlpool behind the title text.

Look, you’re probably in at least one.

For once on the internet, I recommend reading the comments, in that I think they help flesh out the argument a lot more and correct some strawmanning of the heliocentrists by the OP. Interestingly, OP actually says he thinks

In fact, one my key motivations for writing it — and a point where I strongly disagree with people like Kuhn and Feyerabend — is that I think heliocentrism was more plausible during that time. It’s not that Copernicus, Kepler Descartes and Galileo were lucky enough to be overconfident in the right direction, and really should just have remained undecided. Rather, I think they did something very right (and very Bayesian). And I want to know what that was.

and seems surprised that commenters think he went too pro-geocentrist. I recommend the following if you want the detailed correction, but I’ll also summarize the main points so you don’t have to:

  • Thomas Kehrenberg’s comment as it corrects factual errors in the OP regarding sunspots and Jupiter’s moon
  • MakerOfErrors for suggesting the methodological point should be that both geo- and heliocentric systems should have been treated with more uncertainty around the time of Galileo until more evidence came in
  • Douglas_Knight for pointing out a factual error regarding Venus and an argument I’m sympathetic to regarding the Coriolis effect but evidently am wrong on, which I’ll get to below. I do think it’s important to acknowledge that Galilean relativity is a thing, though, and that reduces the potential error a lot.
  • Ilverin for sort of continuing MakerOfError’s point and suggesting the true rationalist lesson should be looking at how do you deal with competing theories that both have high uncertainties

It’s also worth pointing out that even the Tychonic system didn’t resolve Galileo’s argument for heliocentrism based on sun spots. (A modification to Tycho’s system by one of his students that allows for the rotation of the Earth supposedly resolves the sunspot issue, but I haven’t heard many people mention it yet.)

Also, knowing that we didn’t have a good understanding of the Coriolis effect until, well, Coriolis in the 1800s (though there are some mathematical descriptions in the 1700s), I was curious to what extent people made this objection during the time of Galileo. It turns out Galileo also predicted it as a consequence of a rotating earth. Giovanni Riccioli, a Jesuit scientist, seems to have made the most rigorous qualitative argument against heliocentrism because cannon fire and falling objects are not notably deflected from straight line paths. I want to point out that Riccioli does virtually no math in his argument on the Coriolis effect (unless there’s a lot in the original text that I don’t see in the summary of his Almagestum Novum). This isn’t uncommon pre-Newton, and no one would have the exact tools to deal with Coriolis forces for almost 200 years. But one could reasonably try to make a scaling argument about whether or not the Coriolis effect matters based only on the length scale you’re measuring and the rotation speed of the Earth (which would literally just be taking the inverse of a day) and see that that heliocentrists aren’t insane.

It’s not a sexy answer to the second question, but I think “patience for new data” goes a long way towards making you the kind of person who can say yes to the first question. You hear the term “Copernican revolution” thrown around like a very specific event, and I think it’s pretty easy to forget the relative timeframes of major players unless this is your bread and butter. Copernicus’ De revolutionibus came out in 1543. Newton’s Principia came out in 1687, which gives a physical explanation for Kepler’s empirical laws and results in them becoming more greatly accepted, and so can be considered a decent (if oversimplified) endpoint for the debate. Galileo began to get vocal about heliocentrism in the early 1610s. The Almagestum Novum came out in 1651. For over a century, people on both sides were gathering and interpreting new data and refining their theories.

I also like this article for a related point, albeit one a bit removed from the author’s thesis. In considering the question of how should accept new theories, we see the historical development of one theory overtaking another as “scientific consensus”. Earlier this year, rationalist Scott Alexander in a post on Learning to Love Scientific Consensus concisely summarized why the typical “consensus is meaningless” trope of just listing times consensus has turned out to be wrong isn’t particularly useful in understanding science:

I knew some criticisms of a scientific paradigm. They seemed right. I concluded that scientists weren’t very smart and maybe I was smarter. I should have concluded that some cutting-edge scientists were making good criticisms of an old paradigm. I can still flatter myself by saying that it’s no small achievement to recognize a new paradigm early and bet on the winning horse. But the pattern I was seeing was part of the process of science, not a condemnation of it.

Most people understand this intuitively about past paradigm shifts. When a creationist says that we can’t trust science because it used to believe in phlogiston and now it believes in combustion, we correctly respond that this is exactly why we can trust science. But this lesson doesn’t always generalize when you’re in the middle of a paradigm shift right now and having trouble seeing the other side.

The notion of “trusting” scientific consensus I think gets to a larger point. There are way more non-scientists than scientists, so most people aren’t in a place to rigorously evaluate contemporary analogues to the Copernican revolution, so you often have to trust consensus at least a little. Also scientists aren’t scientists of every field, so even they can’t evaluate all disputes and will rely on the work of their colleagues in other departments. And given how many fields of science there are, there’s always probably at least one scientific revolution going on in your lifetime, if not several. Fortunately they don’t all take 150 years to resolve. (Though major cosmological ones can take a long time when we need new instruments and new data that can take a long time to acquire.)

But if you want to be the kind of person who can evaluate revolutions (or maybe attempts at revolutions), and I hope you are, then here’s a bit more advice for the second question à la Kuhn: try to understand the structure of competing theories. This doesn’t mean a detailed understanding of every equation or concept, but realize some things are more much important to how a theory functions than others, and some predictions are relatively minor (see point 4 below for an application to something that I thing pretty clearly doesn’t fall into a revolution today). To pure geocentrists, the phases of Venus were theory-breaking because geocentrism doesn’t allow mechanisms for a full range of phases for only some planets, and so they had to move to Tycho’s model. To both groups writ large, it didn’t break the scientific theories if orbits weren’t perfectly circular (partly that was because there wasn’t really a force driving motion in either theory until Kepler and he wasn’t sure what actually provided it, so we see how several scientific revolutions later, it gets hard to evaluate their theories 100% within the language of our current concepts), though people held on because of other attachments. Which leads to a second suggestion: be open-minded about theories and hypotheses, while still critical based on the structure. (And I think it’s pretty reasonable to argue that the Catholic Church was not open-minded in that sense, as De revolutionibus was restricted and Galileo published his future works in  Protestant jurisdictions.) In revolutions in progress, being open-minded means allowing for reasonable revision of competing theories (per the structure point) to accommodate new data and almost maybe more importantly allows for generating new predictions from these theories to guide more experiment and observation to determine what data needs to be gathered to finally declare a winning horse.

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Stray thoughts

  1. Let me explain  how I corrected my view on the Coriolis effect. We mainly think of it as applying to motion parallel to the surface of the Earth, but on further thought, I realized it does also apply to vertical motion (something further from the center of the Earth is moving at a faster rotational velocity than something closer, though they do have the same angular velocity). Christopher Graney, a physics and astronomy professor at Jefferson Community and Technical College who I will now probably academically stalk to keep in mind for jobs back home, has a good summary of Riccioli’s arguments from the Almagestum Novum in an article on arXiv and also what looks like a good book that I’m adding to my history/philosophy of science wishlist on Amazon. The Coriolis effect arguments are Anti-Copernican Arguments III-VI, X-XXII, and XXVII-XXXIII. Riccioli also addresses the sunspots in Pro-Copernican Argument XLIII, though the argument is basically philosophical in determining what kind of motion is more sensible. It’s worth pointing out that in the Almagestum, Riccioli is collecting almost all arguments used on both sides in the mid-17th century, and he even points out which ones are wrong on both sides. This has led some historians to call it what Galileo’s Dialogue should have been, as Galileo pretty clearly favored heliocentrism in Dialogue but Riccioli remains relatively neutral in Almagestum.
  2. I’m concerned someone might play the annoying pedant by saying a) “But we know the sun isn’t the center of the Universe!” or b) “But relativity says you could think of the Earth as the center of the Universe!”. To a), well yeah, but it’s really hard to get to that point without thinking of us living in a solar system and thinking of other stars as like our sun. To b), look, you can totally shift the frames, but you’re basically changing the game at that point since no frame is special. Also, separate from that, if you’re really cranking out the general relativity equations, I still think you see more space-time deformation from the sun (unless something very weird happens in the non-inertial frame transform) so it still “dominates” the solar system, not the Earth.
  3. For a good example of the “consensus is dumb” listing of consensuses of the past, look at Michael Crichton’s rant from his “Aliens Cause Global Warming” 2003 Michelin Lecture at CalTech beginning around “In science consensus is irrelevant. What is relevant is reproducible results.” Crichton gets close to acknowledging that consensus does in fact seem to accommodate evidence in the plate tectonics example, but he writes it off. And to get to Crichton’s motivating point about climate science, it’s not like climate science always assumed man had a significant impact. The evolution of global warming theory goes back to Arrhenius who hypothesized around 1900 that the release of CO2 from coal burning might have an effect after studying CO2’s infrared spectrum, and it wasn’t until the 60s and 70s that people thought it might outweigh other human contributions (hence the oft-misunderstood “global cooling” stories about reports from the mid-20th century).
  4. Or to sum up something that a certain class of people would love to make a scientific revolution but isn’t, consider anthropogenic climate change. Honestly, specific local temperature predictions being wrong generally isn’t a big deal unless say most of them can’t be explained by other co-occurring phenomena (e.g. the oceans seem to have absorbed most of the heat instead of it leading to rising surface temperatures), since the central part of the theory is that emission of CO2 and certain other human-produced gases has a pretty effect due to radiative forcing which traps more heat in. Show that radiative forcing is wrong or significantly different from the current values, and that’s a really big deal. Or come up with evidence of something that might counter radiative forcing’s effect on temperature at almost the same scale, and while the concern would go away, I think it’s worth pointing out it wouldn’t actually mean research on greenhouse gases was wrong. I would also argue that you do open-mindedness in climate science, since people do still pursue the “iris hypothesis” and there are actually almost always studies on solar variability if you search NASA and NSF grants. 

Thinking of the Urban as Natural

Image result for urban ecology

“Name everything you can think of that is alive.” This was the prompt given to three different groups of children: the Wichi, an indigenous tribe in the Gran Chaco forest, and rural and urban Spanish-speakers in Argentina. It might not surprise you to know that the indigenous children who directly interact with wildlife often named the most plants and animals that lived nearby and were native to the region, and they often gave very specific names. The rural children named a mixture of both native Argentinian wildlife and animals associated with farming. But the urban children were very different from the others. They would name only a few animals in Argentina. Instead, they named significantly more “exotic” animals from forests and jungles in other countries and continents. This result has been replicated in multiple studies on child development. But we shouldn’t be so hard on the urban children.

This reflects a somewhat uncomfortable truth about how we learn. If you live in a city, you mainly learn about nature indirectly, through pop culture and formal science education. In both contexts, it is much easier to find information about “exotic” animals like lions or tigers instead of most of the organisms that make a home in the city. I think this is a symptom of a deeper cultural notion: that somehow cities are “fake” environments divorced from nature. I will argue that this distinction between the urban and natural is not only wrong, but also harmful to our society.

First, we should consider that this notion really only makes sense relatively recently in history. Cities are young in a geological and even anthropological sense, but since we’ve been making them as a species, they have been influenced by nature. We talk about “cradles of civilization” because they were places where the natural environment was well-suited to supporting early, complex social systems and their infrastructure. To use the literal Ur-example, consider the Fertile Crescent region, the convergence of the Tigris and Euphrates rivers. This provided lush soil at several elevations, which supported the growth of a variety of crops and helped with irrigation. And many modern cities can still be traced back to earlier environmental decisions. I am from Louisville, a city by a part of the Ohio River that could not be crossed by boat until the building of locks in the 1830s. The city was founded as a natural stopping point for people before they would go on to the Mississippi River.

Second, it seems incredibly alienating to argue most of humanity is “unnatural”. Since 2008, the majority of humans have lived in cities. By 2050, 70% of the global population will live in urban areas. We should not discourage the growth of cities or devalue them, when their more efficient use of resources and infrastructure is necessary to keep projected population growth sustainable. The smart development of cities recognizes they can help preserve other environments.

Finally, this urban-natural distinction distorts our understanding of the environmental and ecological processes that affect cities and even our broader understanding of the environment. A recent study showed that insects help reduce food waste just as much as rodents in New York City – for every memeable “pizza rat” there’s an army of “pizza ants” getting rid of rotting food. Despite their importance, in New York’s American Museum of Natural History renowned insect collection, they have almost no species native to the city. And since many city-dwellers like the Argentinian children only know about exotic species, it affects animal conservation efforts. Well-known “charismatic” species like pandas or rhinos have support all over the world. Few people are aware of endangered species in urban areas And sometimes scientists don’t even know. For instance, relating to the above, 40% of insect species are endangered, but we don’t know if that number is different in cities.

Instead of rejecting the last few thousand years of our society’s development, we should (re)embrace cities as part of the broader natural world. Recognizing that cities can have their own rich ecological and environmental interactions can help us build urban spaces that are better for us humans, other city-dwelling creatures, and the rest of the world.

(Note: This post is based on a speech I gave as part of a contest at UVA, the Moomaw Oratorical Contest. And this year I won!)

Reclaiming Science as a Liberal Art

What do you think of when someone talks about the liberal arts? Many of you probably think of subjects like English and literature, history, classics, and philosophy. Those are all a good start for a liberal education, but those are only fields in the humanities. Perhaps you think of the social sciences, to help you understand the institutions and actors in our culture; fields like psychology, sociology, or economics. What about subjects like physics, biology, chemistry, or astronomy? Would you ever think of them as belonging to the liberal arts, or would you cordon them off into the STEM fields? I would argue that excluding the sciences from the liberal arts is both historically wrong and harms society.

First, let’s look at the original conception of the liberal arts. Your study would begin with the trivium, the three subjects of grammar, logic, and rhetoric. The trivium has been described as a progression of study into argument. Grammar is concerned with how things are symbolized. Logic is concerned with how things are understood. Rhetoric is concerned with how things are effectively communicated, because what good is it to understand things if you cannot properly share your understanding to other learned people? With its focus on language, the trivium does fit the common stereotype of the liberal arts as a humanistic writing education.

But it is important to understand that the trivium was considered only the beginning of a liberal arts education. It was followed by the supposedly more “serious” quadrivium of arithmetic, geometry, music, and astronomy. The quadrivium is focused on number and can also be viewed as a progression. Arithmetic teaches you about pure numbers. Geometry looks at number to describe space. Music, as it was taught in the quadrivium, focused on the ratios that produce notes and the description of notes in time. Astronomy comes last, as it builds on this knowledge to understand the mathematical patterns in space and time of bodies in the heavens. Only after completing the quadrivium, when one would have a knowledge of both language and numbers, would a student move on to philosophy or theology, the “queen of the liberal arts”.

7 Liberal Arts

The seven liberal arts surrounding philosophy.

Although this progression might seem strange to some, it makes a lot of sense when you consider that science developed out of “natural philosophy”. Understanding what data and observations mean, whether they are from a normal experiment or “big data”, is a philosophical activity. As my professors say, running an experiment without an understanding of what I was measured makes me a technician, not a scientist. Or consider alchemists, who included many great experimentalists who developed some important chemical insights, but are typically excluded from our conception of science because they worked with different philosophical assumptions. The findings of modern science also tie into major questions that define philosophy. What does it say about our place in the universe if there are 10 billion planets like Earth in our galaxy, or when we are connected to all other living things on Earth through chemistry and evolution?

We get the term liberal arts from Latin, artes liberales, the arts or skills that are befitting of a free person. The children of the privileged would pursue those fields. This was in contrast to the mechanical arts – fields like clothesmaking, agriculture, architecture, martial arts, trade, cooking, and metalworking. The mechanical arts were a decent way for someone without status to make a living, but still considered servile and unbecoming of a free (read “noble”) person. This distinction breaks down in modern life because we are no longer that elitist in our approach to liberal education. We think everyone should be “free”, not just an established elite.

More importantly, in a liberal democracy, we think everyone should have some say in how they are governed. Many major issues in modern society relate to scientific understanding and knowledge. To talk about vaccines, you need to have some understanding of the immune system. The discussion over chemicals is very different when you know that we are made up chemicals. It is hard to understand what is at stake in climate change without a knowledge of how Earth’s various geological and environmental systems work and it is hard to evaluate solutions if you don’t know where energy comes from. Or how can we talk about surveillance without understanding how information is obtained and how it is distributed? The Founding Fathers say they had to study politics and war to win freedom for their new nation. As part of a liberal education, Americans today need to learn to science in order to keep theirs.

(Note: This post is based off a speech I gave as part of a contest at UVA. It reflects a view I think is often unconsidered in education discussions, so I wanted to adapt it into a blog post.

As another aside, it’s incredibly interesting people now tend to unambiguously think of social sciences as part of the liberal arts while wavering more on the natural sciences since the idea of a “social” science wasn’t really developed until well after the conception of the liberal arts.)

Quick Thoughts on Diversity in Physics

Earlier this month, during oral arguments for Fisher v. University of Texas, Chief Justice John Roberts asked what perspective an African-American student would offer in physics classrooms. The group Equity and Inclusion in Physics and Astronomy has written an open letter about why this line of questioning may miss the point about diversity in the classroom. But it also seems worth pointing out why culture does matter in physics (and science more broadly).

So nature is nature and people can develop theoretical understanding of it anywhere and it should be similar (I think. This is actually glossing over what I imagine is a deep philosophy of science question.) But nature is also incredibly vast. People approach studies of nature in ways that can reflect their culture. Someone may choose to study a phenomenon because it is one they see often in their lives. Or they may develop an analogy between theory and some aspect of culture that helps them better understand a concept. You can’t wax philosphical about Kekule thinking of ouroboros when he was studying the structure of benzene without admitting that culture has some influence on how people approach science. There are literally entire books and articles about Einstein and Poincare being influenced by sociotechnical issues of late 19th/early 20th century Europe as they developed concepts that would lead to Einstein’s theories of relativity. A physics community that is a monoculture then misses out on other influences and perspectives. So yes, physics should be diverse, and more importantly, physics should be welcoming to all kinds of people.

It’s also worth pointing out this becomes immensely important in engineering and technology, where the problems people choose to study are often immensely influenced by their life experiences. For instance, I have heard people say that India does a great deal of research on speech recognition as a user interface because India still has a large population that cannot read or write, and even then, they may not all use the same language.

What is the point of thesis/dissertation committees?

I ask this in all sincerity, because after talking to other students in other schools and other fields, I don’t seem any closer to an answer. Maybe it’s just because I think my department is weird, because we don’t assemble dissertation committees until we propose, and we propose fairly late (it’s pretty common for people to propose only a year before they plan on defending).

The closest thing to a consensus answer I can find is that committees exist to make sure advisors aren’t just handing out degrees. But if that is the case, it seems like there isn’t really a guarantee the average committee that doesn’t do much more than read the proposal and the dissertation would be effective at that. A group of less than half a dozen people who typically have two weeks to read a ~200 page summary of what is usually years of research can’t really independently verify the results that are presented. And if a professor really was intent on just handing out degrees to their lab, they could help make that data look more convincing. (I’m not saying this happens a lot. I don’t know for sure, but I don’t think so. My point is just that it seems easy to work around the supposed purpose of committees.)

I thought the point of a dissertation committee was to be a real committee, which in my mind means that at least part of it’s power comes from the fact that it is a group. Advisors can be great and all, but sometimes you need the perspective of other people to plan an experiment or help think through an interpretation of results. I thought the committee could help mediate part of the intellectual relationship between the advisor and student. Say a student wants to redo or alter some experiment but the advisor doesn’t think that it is worth the time; the student can try to convince the committee as a group of intellectual peers, and if they agree, they can essentially override the advisor’s wishes on behalf of the student. I think this is key because it can help diffuse some negative feelings in conflicts like this away from the student. (I don’t think the committee should take on issues that rise to the point of breaking up the advising relationship. Though if this works, I also think fewer issues should lead to the break up of the relationship.) I’m not sure if the converse matters as much because advisors do generally have a lot of control over what their students do, but if an advisor felt the student wasn’t doing something well, he or she could have the committee make it clearer.

So I’ll close with two questions I would love to hear answers from people in other graduate programs. First, when does you first assemble your committee? Second, what does your committee do?