Saturday, June 18, 2016

My Writing Process

I haven't done any new research in a while, but I have been writing. This past year, I wrote a fiction book for my senior thesis, and one of the most common questions I heard (especially from my science-y friends) was, "What's your process?"

Okay, keep in mind that that is a seriously vague question, and one that probably doesn't have a single answer because I don't always do the same thing everything I sit down to write. But I realized that I did have to make a series of decisions in the process of writing this book, and I wanted to share that series with all of you.

Step 1: Decide why you're writing
Writing is hard work. It's mentally and emotionally exhausting, so there will come a time when you want to give up. But if you know why you're writing, it'll be easier for you to keep going.

And the reason doesn't have to be profound or noble in any way. I started writing my book because it was the only project my college advisors approved for my senior thesis. I literally dedicated the book to my desire to graduate. Maybe you're writing because you have an idea you want to share. Or maybe you just want to make money. It doesn't really matter what your reason is; just make sure you have one.

Step 2: Choose a genre
I think this step is pretty obvious. My genre was kind of chosen for me, since my book had to be something that combined astrophysics and folklore. But knowing the genre ahead of time really helped narrow things down later.

Step 3: Pick a point of view
I can't guarantee this step should be your #3, but it worked for me.

When I was first thinking about the book, I was totally overwhelmed by all the choices I had to make and terrified by the extent of the world I had to create. I needed a way to narrow my world, and point of view was the perfect way to do that. By choosing first person, I was only agreeing to create parts of the world the main character would reasonably see.

But maybe you aren't limited by your imagination like I was by mine. Maybe you have too many things you want to show your readers. Whatever your worries are, point of view is a nice way to set up the world so that you share exactly as much with your readers as you want to.

Step 4: Create a character
I started by creating a single character because my book was in first person POV. Regardless of your POV, though, creating characters is a great next step because it helps everything else fall into place.

My professor in my last creative writing class stressed over and over again the superiority of character-driven narratives over plot-driven ones. She said they're more immersive stories, and I completely agree, but it's more than that.

When you create a character first -- and I mean really create a character, so that you know their strengths, flaws, and interests -- you'll be able to come up with a plot that the character would actually engage with. The small details and subplots of your story will come naturally, almost as if the characters are acting for themselves and you're just writing down what they do.


Everything after those steps was just late nights spent writing and lots of begging my friends to read drafts. I hope this helps, but in case it didn't, here's a video of an adorable Irish pug.






Sunday, September 6, 2015

Hordes Are Made of People, Too

A few months ago, I was casually scrolling through my Facebook newsfeed when I saw a post by Dr. Chanda Prescod-Weinstein about people protesting the construction of a telescope in Hawai'i.  I didn't think much of it at the time, but kept scrolling and eventually went back to watching some terrible sitcom on Netflix. Some time after that, my Facebook and Twitter feeds exploded with stories about that same telescope. Suddenly, I couldn't look at any form of social media without hearing about Mauna Kea or the Thirty Meter Telescope (TMT). I started paying attention then (after all, when Khal Drogo sends a message, you better listen), and now I have lots of feelings about the subject.


For those of you who aren't friends with a lot of socially aware astronomers on Facebook and didn't get that same barrage of TMT news, here's what's going on:  Astronomers want to build the TMT on top of Mauna Kea in Hawai'i.  Mauna Kea is a sacred mountain. There are many people in Hawai'i (and elsewhere) who would rather the astronomers build their very large, very destructive telescope somewhere else.  

I started actively seeking out articles about this conflict, written from both perspectives. I found lots of astronomers who support the construction TMT and I found lots of astronomers who oppose it.  You know what else I found lots of? Language that lumps entire groups of people into one single being. It's "the protesters" this, or "the Protectors" that (if the author knows what's up), or "horde of native Hawaiians attacking" (if the author really doesn't know what's up).  And that's not cool!

I'm not really here to to talk about what I think of the TMT. That's a topic for another blog post. But regardless of what side of this argument you're on, it's important for everyone to realize that this movement is made up of individuals, each with their own backgrounds and motivations for being involved. I recently had the opportunity to spend some time on Mauna Kea and meet some of the people those articles are about. I'd like you to meet them, too. (Anonymously, of course, because ain't nobody got time to rudely give away people's identities without their permission.) 

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S was the first person I met when I approached the Protector tent, shy and awkward and totally unsure of how to initiate conversation.  Within 30 seconds of meeting me, S gave me a hug and offered me a donut. He won me over then and there. He won me over again when he told me that he "used to be just a normal guy" until a few months ago, when he heard about the TMT and all of the consequences its construction would have. He quit his job and bought a one-way ticket to Hawai'i island, and he's been there ever since. 

The first time I saw P, he was answering questions about his plans to repopulate the native plant life on Mauna Kea. When I asked him about it later, he talked about the different kinds of plants he wanted to bring back and their various purposes, some of them medicinal. He heard I was an astronomy student and got so excited, not angry like some of the articles led me to expect.  When I hugged him goodbye, he was on his way out to the garden to plant some more herbs I had never heard of. 

T is a farmer who lives close to the mountain. She and her partner practice a specific kind of farming that uses the natural waterflow that comes off of Mauna Kea. In between telling me about the damage the TMT would do to one of the largest aquifers on the island, T offered me chili, fruit, and a local tea that she had brought up the mountain for lunch.  She told me my name sounded like the Hawaiian word for "to dream" and we bonded over a love of science. We touched noses before she left. 

L has been on top of the mountain almost every day since people started occupying the mountain in response the first attempts to break ground for the TMT.  He's a teacher, and he's fluent in Hawaiian.  When I told him I was trying to learn a little bit of the language, he sat down with me for 20 minutes to go over some basic vocabulary. l asked him why he was there. He said he felt a responsibility to his family, to his aunt who signed the anti-annexation petition back in 1897.He talked about the power of love to fix all troubles, and I kind of felt like I had been transported back to the 60's, but I was into it.

K is a college student just like me, studying environmental science. She knows people who have dropped out of school to become involved in the movement.  Like most of the others, she offered me food, but it was my first day on the mountain and I was too shy to take it. She asked me why I was there, and when I told her, she led me around and introduced me to people, making sure I knew I was welcome. 

J and R are the sweetest married couple. He's been retired for over 10 years and she's excited to retire next year. They've only been off the island once. J heard that I was an astronomy student there to ask questions for my senior thesis and offered to give me a tour of the land. She showed me plants that looked like swords sticking out of the ground and bushes that smelled like fish when I rubbed them. When R got back from wherever he had been, she asked if I wanted to go hiking with them. We hiked to the top of a sizable hill, and along the way, they told me about their children, life-long friendships, marathons they had run together.  They promised me a place to stay if I ever found myself in Hawai'i again and I made them promise to look me up if they ever found themselves in Boston. 

These are just a few of the people I had the pleasure of meeting, but I think you get the picture. 
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When we talk about groups that form around controversial matters, like the Protectors or Black Lives Matter, we have this tendency to remove their humanity.  We talk about them as if they're a Borg cube, sharing thoughts, plans, and motivations. I don't know which is the chicken and which is the egg here, but when we do this, it allows a few things to happen:
  1. It's easier to perform (and write about) inhumane acts that are direct consequences of racially charged colonization if you don't focus on the victims as humans.
  2. It makes it so that the actions of one person, no matter how far removed they are from the group's agenda, represent the entire movement. 
  3. It justifies condemning the group for being "disorganized."  Neither the Mauna movement nor BLM claim to have centralized leadership, yet we expect them to act as if they do because of the way we present them in the media. 
It's time to stop this and get to know the individuals within the horde. Maybe then we would see our actions, past and present, in a different light. 

Thursday, August 20, 2015

Faces Like Mine

I spent so much time this summer discussing racism, sexism, and any other (legitimate) "ism" you can think of.  I sat in discussion circles where we learned vocabulary, talked about historical events and motivations that lead to the conditions we have now, and brainstormed on how to enact real and positive changes in our society.  In all of those discussions, the one thing that never failed to be mentioned was representation in the media.

I'd now like to direct your attention to this video:


 When discussing race, there are a few questions that are bound to come up.
  • Why are there so few people of color in STEM fields? 
  • Why are crime rates among Blacks and Latin@s so high? 
  • If white people can realize the American Dream and make successes out of nothing, why can't POCs? 
There are so many historical, political, and economic answers to those questions.  But this blog post is going to focus on one: representation of POCs in the media.

I've heard several times (mostly from older white men) that women and POCs aren't very present in STEM fields because they just aren't interested in STEM.   I'm sorry, what?  You mean to tell me, old white dude, that entire demographics of people are significantly less interested in science and math than you are? I gueeeeeeess that could be it.

OR, could it be that we (the women and POCs) are taught practically from birth that we don't belong in those fields?  My mother is a hardcore feminist, but even she gave me dolls to play with as a young child instead of trucks or toy rocket ships.  I watched Star Trek and Contact and Star Gate and countless other space-themed things growing up.  And you know what I learned from them?  I learned that, unless I was lucky enough to be the ONE black person in a cast of about 100, I didn't really belong in the field. All of that worked together to make it so that I didn't actually believe I could make it as an astronomer until last summer. LAST SUMMER!! That's absurd.

I've talked to people who believe that Black and Latin@ communities have higher crime rates than white communities because there's something about those racial groups that makes the people in them morally inferior to whites.  Now, I feel the need to make it abundantly clear that I'm not condoning (most) crimes.  But (ignoring the fact that Black and Latin@ people are more likely than whites to be persecuted for identical crimes, source here) perhaps there's a reason more Black and Latin@ people feel it's necessary to turn to a life of crime? Could that reason maybe be the fact that most roles in movies and on TV for Black and Latin@ actors revolve around crime?  I think it might be.

And finally, I've literally had people say to my face that white people can work their way out of poverty because they work hard and Black and Latin@ people are lazy.  I don't know about you, but there's just something about characterizing entire races of people like that that doesn't sit right with me. Instead, I wonder if it might have something to do with the fact that most AMerican Dream movies are about white people.  Maybe, if POCs saw people who look like them succeeding just as often as they see whites succeeding, they would start to see it as a possibility.  Because I guarantee that there little Black and Brown children in this country who don't even think success is something they should dare dream about.


This might be the point in the blog post where you say, "But Moiya, what about all those great Black and Brown athletes and singers? Aren't they good role models?" 

Yeah, sure.  Of course there are a few bad apples **cough cough** Chris Brown **cough cough** but for the most part, Black and Brown performers let young Black and Brown people know that they could make it big one day.  There's just one problem:  They're only performers.  I'm not saying that to belittle those professions, but what about the little Black boy who wants to grow up to be a lawyer, or the young Latina girl who wants to be a marine biologist?  Who are their role models? They don't have any, and that's truly heartbreaking. 

I'm not saying that all of the prejudices in the world would disappear if Hollywood and other major film and television institutions suddenly decided to cast POCs, but it sure would make a hell of a difference

Summer Reflections

Another summer internship season has come to a close.  My projects have wrapped up, I've given my presentations and handed in my papers, and I've said my goodbyes. Tho only thing I haven't done -- because the last two weeks have been such a whirlwind of science, presentations, and moving -- is reflect on what this summer has meant to me, so that's what I'm going to do in this blog post.

Science
In case you haven't devoted most of your attention to following my blog and remembering everything I've ever written (and I guess I can't really blame you too much if that's the case), I spent the summer researching the exoplanet system Kepler-186.  I did other things too, mostly regarding galaxies, but this project has a more concrete result, so I'll focus on it.

Kepler-186 is about 500 lightyears (\(\approx\)150pc) away.  The system is made of 5 planets orbiting an M-dwarf star (about half the size and mass of our own sun, but less than 10% the brightness of our sun).  The 5th planet, K-186f, is famous in the exoplanet community.  Hell, it's even famous outside of the astronomer community, as evidenced by the fact that it has its own Wikipedia page.  Its fame comes from the fact that it's practically Earth-sized (\(1.06 R_{Earth}\), according to my calculations) and is just the right distance away from its star that it could hold liquid water. 

There are some downsides to this system being so famous.  Mostly, it just means that any work I do regarding this system won't be new, but that's okay. I wasn't really looking to do completely original research this summer.  I wanted to do research that could form a scientific basis for the book I want to write as my senior thesis, and that's exactly what I did.

The big question I had to ask about K-186f was, "Is it habitable?"  Well, here's my answer in picture form:


Obviously, we don't have the technology yet to go and visit this planet, so we can't answer this question with certainty.  All we can do is run the planet through "habitability tests" and see if it could pass. The plot above shows that it (probably) passes the first few tests we put it through. 

The first is the Planet Test.  The dashed line at the bottom indicates the radius of the smallest exoplanet we've ever found (just slightly larger than the moon).  All of the planets are above that line. Yay.

The second is the Composition Test.  There are roughly two types of planets: rocky and gaseous.  Since it's pretty difficult for is to stand on gas, a planet has to be rocky for it to be habitable. The dashed line at the top of the plot shows the radius at which planets tend to stop being rocky, according to Leslie Rogers and her collaborators. All of the planets are below that line. Another yay.

The third and traditionally most important test is the Liquid Water Test. The grey box shows the range of distances from the host star where the temperature on the planet could be just right to hold liquid water.  You can see that K-186f spends its entire orbit (the width of the points represents the range of distances from the star that the planet experiences throughout its orbit, because none of the orbits are perfectly circular) in this Goldilocks Zone. A third yay!  

There are still other tests that we need to put K-186f through, but I'm happy with three yays for now.


Feelings 
I'll admit that I was a little bit jaded at the beginning of the summer. I knew I was going to do an exoplanet project but was convinced that I hated exoplanet research.  I was just as convinced that no group of people would ever be able to compare to the friends I made at NRAO last summer.  And, if I'm being honest with myself and you, I wasn't too happy about being part of a program meant exclusively for Black and Brown students.  It felt like I was cheating or receiving special treatment or admitting that I wasn't good enough to compete with the white kids.  (None of those things were true, of course, but I can't control the thoughts that run that deep in my head.)  It wasn't long before all that jade faded away.

I haven't forgotten about galaxies.  I still think they're really, really cool.  But I now realize that I shouldn't completely write off exoplanets as the most boring area of astronomy research.  I actually think they're, dare I say it, fun to study.

The NRAO kids from last summer are still some of my best friends -- both in and out of the astronomy community -- but I got pretty damn close to the Banneker kids, too.  And as much as I love my NRAO friends, I didn't need them as much as I needed my Banneker friends.  That was actually the best part of this summer. Being around so many talented Black and Brown people and forming such close relationships with all of them was literally a life changing experience.  It alleviated some long-held biases of mine, ended my life-long habit of not feeling "black enough" to spend time with other Black people, and opened my eyes to so so so many issues that exist, hidden, in our society.

I know this blog post wasn't the most well-written.  I had a lot of thoughts and just needed a way to get them out of my head.  The gist of this post, though, is that I needed this summer more than I ever could have realized.

Tuesday, July 28, 2015

Anti-Racism MUST EQUAL Anti-Sexism

I love Key and Peele.  Their sketches occupy at least 5 of top 10 spots on my list of favorite internet videos.  But lately, watching their videos has made me increasingly uncomfortable.  I'd like to take this moment to simultaneously thank the Banneker Institute and curse it (okay, not really that second one) for opening my eyes to the things in the world that I'm now starting to identify as problematic.

The show just premiered its fifth season. If each season has a dozen or so episodes and each episode has 4 or 5 sketches, that means there are about 200 K&P videos floating around the internet. That's a lot of videos to comb through and analyze for potentially (most likely unintentionally) offensive content. To spare you all that, I'll just talk about one(ish) in this blog post.

That one is Negrotown.

 

It's funny, right? And it's a catchy song with lots of cool dance moves and flashy outfits, all of which are things I really appreciate. It even provides a really nice satirical commentary on the current state of affairs in America.  

If you doubt that any of the things alluded to in this video are true, I encourage you
  1. Watch this TED Talk on the the injustice of our so-called "justice system" 
  2. Look up names like Sandra Bland, Eric Garner, Tanisha Anderson, and Tamir Rice.  Honestly the list of names could go on and on; these are just a few of the well-known ones. 
  3. Read books like Claude Steele's Whistling Vivaldi or Jean Halley's Seeing White.
  4. Or, if all of that is too much, literally just spend 5 minutes watching the news or scrolling headline stories on the internet, because this shit is everywhere. 
If you already believe that the things K&P mentioned in the video are indeed real, then you're ready for this next bit.

Go back to the video and start watching at \(\approx\)2:45.  This video is about the issues that Black people in America face, right?  Then why is it that the only complaint the Black women of Negrotown have is against other women and about their relationships with men??  I'm pretty sure Black women have bigger problems than "white women [taking black men] away." 

Maybe I shouldn't be making assumptions about the concerns of an entire demographic, but I'm definitely more worried about the fact that the median net worth of single Black women is less than 100 dollars, but the median for single white women is more than $40,000 (source here).  And about the fact that the infant mortality rate among Black women is more than twice that among white women (source here).  And about the fact that Black women earn 89 cents for every dollar that Black men make, and only 64 cents for every dollar a white man makes (source here). And so many other things.

I recognize that this video does not embody the entire Black rights movement. Nor is it demonstrative of the tone of every K&P sketch (some of them are incredibly feminist).  But it makes a nice litmus test for the mood of the movement.  Just as the problems solved in Negrotown are mostly those faced by Black men, or maybe I should say just as so few of the problems solved in Negrotwon are those faced by Black women, too few of the problems addressed by Black rights movements are aimed towards improving the lives of Black women.

I've participated in a few Black Lives Matter rallies and marches. And in each one of those few, we chanted one or two Black women's names, but the list of Black men's names went on and on.  Is this because only a couple Black women are being unjustly killed? Hell no!  It's because, though there might be a significant intersectional feminist movement, there isn't really an emphasis in most Black rights groups on intersection anti-racism. 

We should change that. 

Wednesday, July 22, 2015

Ian Czekala and Starfish

This blog post is a collaborative effort with fellow Banneker student, Justin Myles, who demonstrates brilliance in all aspects of his life, even though he goes to Yale.


Last week, our advisor John Johnson assigned us the task of finding a graduate student at the Center for Astrophysics and talking with them about their research.  His reason for giving us this assignment was many-fold.
  1. It provides us with a (mandatory) opportunity to get to know one of the grad students in the department.
  2. It gives us a chance to learn about a topic of research that might not necessarily be super close to our own.
  3. The grad student we choose to “interview” gets free publicity.
It’s a win-win-win.  


That night, Justin and I both went home and scrolled through the list of CfA graduate students.  We both found Ian Czekala, and didn’t realize our overlapping intentions until the next morning, when we decided to do this project together.  (Who said Yalies and Harvard students couldn’t work together, huh?)


Ian, who had his first research experience as a summer student in primarily studies young stars and circumstellar disks. One of his recent achievements is developing a package called Starfish which fits an entire spectrum. This is a novel approach to spectroscopy, which is often limited to a narrow range of wavelengths (despite a wide range of data being collected) and a small number of species (e.g. Fe and Na). Starfish is written in Python, available on Github, and utilizes statistical methods -- all subjects which we’ve been learning about in class in the mornings. So we were both interested in learning more about Starfish.


Where other spectral fitting packages focus on fitting the spectral line itself, Starfish focuses on minimizing the residuals (or the difference) between the observed spectrum and the model while accounting for the covariance introduced by systematic discrepancies in the models.
Screen Shot 2015-07-20 at 5.05.20 PM.png
In the above plot, the synthetic spectrum is shown in red and the data are in blue. The residuals are in black. Zooming in to the gray region, we can see a region in the residuals in which the noise is clearly not simply Poisson noise:

Screen Shot 2015-07-20 at 5.08.48 PM.png
An autocorrelation reveals that there is significant correlation on scales roughly the size of a spectral line:

Screen Shot 2015-07-20 at 5.14.08 PM.png


In each row of this plot, the left plot is the covariance matrix, which illustrates the covariance of adjacent pixels and the right plot shows the residuals of the synthetic spectrum fit to the data. It is computationally expensive to interpolate spectra, which is why the following method is useful: by identifying a region of relatively large residuals, and scaling the covariance values to be larger, the residuals decrease. This is shown by the progression from the first to the third row.


In particular, by adding first a global, then a local kernel to the covariance matrix, random draws influenced by the covariance matrix accurately predict the residual noise and in this way model the residual noise.


At this point, you might be wondering how Starfish could be used by the wider astronomical community.  Well, stellar astronomers aren’t the only people who deal with spectra.  Spectroscopy is a tool used in every sub-field of astronomy.  


Let’s say, for example, that you are an astronomer who studies the formation and evolution of galaxies.  (Though there are definitely some people who claim that studying galaxies is nothing more than studying large groups of stars at once.)  You’re working with several spectral lines from a single galaxy, trying to use them to determine the galaxy’s physical characteristics. How do you do that?


The short answer is: make a bunch of model galaxies and compare the line fluxes from those models to the actual line fluxes you observed.


That takes So. Much. Time. Modeling a galaxy is hard work for a computer.  Modeling a few thousand slightly different galaxies? Starfish could take off some of the strain by first identifying the model spectra that best match the observed lines. Using a flexible likelihood function like that advocated by Czekala et al. '14 would deliver realistic parameter estimates and uncertainties, while also potentially identifying any particular lines that are treated incorrectly by the models.

Monday, July 20, 2015

Prior Expectations and Bayes' Theorem

I am the most naive and gullible person I know.  I mean, I'm the reason they have those announcements in airports telling you not to accept any bags from strangers.  That's an extreme case, but there are more realistic applications of my gullibility, too.  Coin flipping, for example.

Coin flipping is my go-to method of settling disputes.  But that method is only fair if the coin is fair, meaning it's just as likely to return Heads as it is to return Tails.  That's not always the case, and this blog post is going to tell you why.

First, I'll start with a simple description of Bayesian Statistics.  As far as I can tell, this is exactly like the statistics we've been doing, but instead of letting the data dominate every step in the fitting process, we have things called "priors."

Priors are just expectations you have about what the parameters you're trying to find will be.

Let's say, for example, that someone hands you a bowl of ice cream, but doesn't tell you what it is.  You have a set of expectations -- or priors -- about what that ice cream will taste and feel like based on your experience (in science, that experience can be your own or it can be knowledge gleaned from already-done studies).  You expect that ice cream to be sweet and cold, right?  Well, plot twist! It's bacon ice cream.

Now that you've taken that bite and recovered from the initial shock, will you expect the next bite to be sweet? No, you know it's going to taste like bacon.  This is because you've adapted your expectations -- or modified your priors -- to match the data you observed when you took that bite.

In math language, this process looks like this:

$p(a|D) = \frac{\pi (A)\emph{L}(D|a)}{E}$

where \(\pi (A)\) is your prior expectation for parameter A (the flavor of the ice cream) and \(\emph{L}(D|A)\) is the likelihood of observing your Data D if A were true (what's the likelihood that you're eating ice cream if it tastes like bacon).  E is just a scaling factor used to represent the evidence you gather as you conduct more research. 

We wanted to test this out to gain a better understanding. We didn't have any ice cream readily available (and I wouldn't really want to eat bacon flavored ice cream, anyway), so we flipped coins instead.  In this case, the question we were trying to answer is: Is this coin fair?


We used an Oregon quarter from 2005 (with the custom state design, not the standard eagle) to conduct this test.  We flipped it 20 times and recorded how many times it returned Heads. 
We started with a prior of .25, meaning the coin should return Heads about once every four flips.  This was actually cheating a little, for the sake of learning.  We actually expected the coin to return Heads about half the time, but we wanted to see how the prior can be overtaken by the observed data. 

I don't know if it was a self-fulfilling prophecy type thing or if the coin was actually unfair (I'm leaning slightly toward the latter), but the coin returned Heads 5 out of 20 times. We plugged those numbers into our equations for likelihood and then plugged those numbers into the probability equation above, and voila! 


Everything converges around .25, which tells us that the probability of that 2005 Oregon quarter returning Heads really is 1 in 4.  I guess I know now which coin I'm using if I ever want to settle a dispute with someone.  

But, we weren't done.  Our data just happened to serendipitously match our priors.  That's great for science, I guess, but it's not all that great for learning.  So I re-did the analysis with the exact same numbers, but with a different prior, this time telling my computer that I expect the coin to be fair.  This is what I got:

The lines all appear to have the same amplitude because they've all been normalizes to have an amp of 1.  In reality, the lines corresponding to higher Ns would have smaller amplitudes because they represent smaller likelihoods.

Here, you can see that the prior is 0.5 and the first line is close to that (the green line corresponds to the point in the trial where we had flipped the coin 5 times and it had returned Heads twice).  But the others are far away from being fair.  They are closer to .25, which is the true probability of the coin returning Heads.  

I really liked this exercise.  It provided me with empirical evidence that there's a flaw in the way I view the world.  If something as basic as a quarter can lie so egregiously to me, I should really try to dial back that gullibility.