Welcome to unit three of writing in the Sciences. In the first two weeks of this course we talked about key principles of effective writing, cutting clutter and using strong, active verbs. This week we're going to continue our discussion of good writing. We'll start by talking about how to improve sentence structure, and we'll build up to writing strong paragraphs. In this first module I'm going to talk about experimenting with punctuation. This is not a course on grammar or punctuation. But I do want to try your attention to some key punctuation marks that you may be neglecting in your writing. These are the dash, the colon, the semicolon, and the parenthesis. You may have been told somewhere along the way that it's improper to use these punctuation marks in scientific writing. That they are a little too exotic or a little too informal. In fact, these are perfectly fine tools to use in scientific writing, if you use them correctly. Pick up a book or a magazine, or any source of professional writing, and read it carefully. You'll notice that professional writers use this punctuation marks all the time, and that's because they are super handy. They have many excellent uses, in particular, they allow you to vary your sentence structure. Up until now, I've been showing you how to strip all the extra words out of your sentences. But this doesn't mean that I want you to write with only short and simple sentences. Prose that consists of only short and simple sentences is very monotonous, very boring. I'm going to encourage you instead to vary your sentence structure. Some of your sentences can be short and simple, but you also need to include some longer and more complex sentences. It's hard to vary your sentence structure, if you are limited to just commas and periods. To make your sentence structure creative, and interesting, and complex, you need the dash, the colon, the semi-colon, and the parentheses, as I'm going to show you now. I'll start with an example. Before he left office President Obama guest edited Wired Magazine. He wrote an essay in that issue and I've provided a link to his essay here. I'm going to to be drawing on examples from his essay in this module. This sentence says, but what really grabbed me about the film is that it shows how humans---through our ingenuity, our commitment to fact and reason, and ultimately our faith in each other---can science the heck out of just about any problem. I love that use of science as a verb, we can science the heck out of it. Obama actually borrowed that usage from the movie he's referring to here, The Martian, but it serves to illustrate how verbs move sentences along better than nouns as we talked about last week. And besides that cute use of science as a verb, the other reason I'm showing you this example is that this sentence has a complex and compelling structure. It's not simple and boring. President Obama has used the dash here to make an engaging sentence. And the dash is one of my favorite punctuation marks, because it's so versatile. You can throw a whole extra thought, or list, or tidbit, or description right into the middle of a sentence like this and it works. Here's another example. Now this was from a paper I was editing I used a colon to take three simple boring sentences and aggregate them into one more complex sentence. The original was, many types of cells in tissue develop a kind of directionality. Certain events happen toward one end of the cell or tissue or the other. It's a phenomenon called cell polarity. That's okay, but it's a bit boring and monotonous, right? All three sentences have the same simple structure. Also, the point here is just to define polarity and it doesn't seem like we need three sentences to do this. So what I did was to use a colon to pull all these pieces together. My rewrite reads, Many cells and tissues develop a kind of directionality, called cell polarity: certain events happen toward one end of the cell or tissue. I used the colon here to set up the definition of polarity, and the sentence is more interesting, efficient, and elegant than the original. For the rest of this module I'm going to teach you how to use these punctuation marks. In their book, Strunk and White explain the punctuation marks in terms of their power to separate, and I think this is a good way to think about it. The comma has the least power to separate it gives the shortest pause. And the period has the most power to separate because it denotes a complete stop. But in between are these four other fun and useful punctuation marks. The colon gives a bigger pause than the comma. The dash gives an even bigger, more abrupt pause. The parenthesis is used to slip something extra into a sentence, so it's a big pause. And the semicolon is a near complete stop because it separates two related sentences. Strunk and White also point out that the dash and parentheses are considered slightly less formal than the comma, colon, semicolon, and period. That's why in the past you may have been discouraged from using the dash and parentheses, but they were fine to use. The fact that they are slightly less formal just means that you want to use them more sparingly. You don't want to overdo it. You shouldn't have a dash or a parentheses in every sentence for example. I'm going to start with the semicolon because I suspect that many of you are all ready comfortable with the semicolon. The semicolon is used to link two independent clauses, basically two small sentences. I'm going to be using the word clause today. In case you're unfamiliar with that term, a clause always contains both a subject and a predicate, that is a subject and a verb. An independent clause is just a small sentence. It has a subject, a predicate and it expresses a complete thought. So here's my example of use of the semicolon. Kennedy could be a cold and vain man, and he led a life of privilege. But he knew something about the world; he also cared about it. In that second sentence, we have two short sentences that have been linked together with a semicolon. Now think about how this sentence would have read had we punctuated it differently. What if we used a comma? It would be he knew something about the world, and also cared about it. You can hear that with a comma, we lose the emphasis on the he also cared about it part. What if we used a period here? It would read, But he knew something about the world. He also cared about it. Using a period here We use the connection between those two ideas, so that it changes the feel of that sentence. Another classic example is from Dickens. It was the best of times; it was the worst of times. Now, clearly, the semicolon is playing an important role here, because it's joining those two ideas. It would completely change the feel of it if you used a comma or a period here. For this prose to work, those two opposing ideas need to be linked with a semicolon. Another use of a semicolon is to separate items in a list. Specifically, you need a semicolon when you've got a list of items where the items in the list contain internal punctuation. If some of the items in the list contain commas, then the comma is no longer sufficient to separate the items in the list. You won't know where the boundaries are, so here's an example. It happened because people organized and voted for better prospects. Because leaders enacted smart, forward-looking policies. Because people's perspectives opened up, and with them, societies did too. Notice there are commas within the last two items in the list here. We get smart, forward-looking. Opened up, and with them, those commas mean you can no longer use commas to separate the items in the list here. You need to use semicolons. That's another important use of the semicolon. All right, moving along to the parentheses. Parentheses are use to insert an afterthought, an explanation, or some additional details. The key is that the sentence is grammatically complete without the material in the parentheses. In other words, you should be able to completely remove that material and it shouldn't change the main point of the sentence. In fact, when you put material in parenthesis, you are actually giving your reader permission to skip over it entirely if they want to. So it's a way you can slip in some extra information or an interesting but non-essential tidbit to your reader. Here’s an example, this was from an article on seahorses. It says, they also have a specialized tail, kind of like a monkey’s tail, that allows them to cling to a piece of grass, or a lucky diver’s finger. Notice the author slipped in a little aside here, it’s not essential, you can take it out and the sentence still reads fine. But it's a nice little detail that adds to the richness of the sentence. The next example is actually, from an article that I was writing about statistics. And I slipped in a little joke. This is me taking a risk in writing, just as I've encouraged you to do. I don't know if the joke came off all right, or not. But anyways, I slipped it in there with some parentheses. It says, this is troubling because, while there are plausible biological stories to connect red meat with cancer and heart disease, it seems unlikely that eating too much red meat could directly cause accidents and injuries. Unless, as one of my students quipped, red meat eaters are swerving to avoid cows. That last part is my attempt to entertain the reader. Notice that I slipped in a whole sentence in parentheses, this is allowed. Moving now to the colon, the colon has several uses. But it always has to come after a clause. That means whatever comes before the colon has to have both a subject and a verb. The colon introduces something. It can introduce a list, a quote, an explanation, a conclusion, or an amplification. I'll give you examples of each of these. Strunk and White says, the colon has more effect than the comma, less power to separate than the semicolon, and more formality than the dash. Here’s an example from Watson and Crick's famous paper on the structure of DNA. They say, the hydrogen bonds are made as follows. And then we get a list of the base purines. Purine position 1 to pyrimidine position 1, purine position 6 to pyrimidine position 6. A few more examples. The first example says, that's one reason why I'm so optimistic about the future, the constant churn of scientific progress. Before the colon we get the setup that tells the reader, hey there's a reason I'm optimistic and I'm about to tell it to you. And then, after the colon we get the reason. You can see how the colon serves to place emphasis on the reason, on the constant churn of scientific progress. In the second example, the column said of a punch line. It says, the woman suffers from lack of experience and a chronic democratic disease, compound sentences. By using a colon, we're building up the reader's anticipation. We are getting them ready for the punchline. Colons can also introduce lists and quotes. So here's an example. The ask not line follows those right after an exhortation modeled on Franklin Roosevelt's rendezvous with destiny. And then the colon sets up a single quote here. In the long history of the world, only a few generations have been granted the role of defending freedom in its hour of maximum danger. I do not shrink from this responsibility, I welcome it. The second sentence, we have a colon that sets up a list of quotes. The note throughout is one of alarm, the trumpet summons us again, the burden of a long twilight struggle, that uncertain balance of terror. I want to point out one other thing here. Notice that in that second sentence, we get exactly three quotes from FDR's speech. Now the author here could have picked two examples, or four examples, or five, but he picked three. When in doubt about how examples to share, three is often a good number. In fact, there's a principle known as the rule of three's. The rule of three's says that when it's arbitrary, how many examples you print percent, three is a pleasing number. It's enough to make the point, but not so much that it overwhelms the reader. Now, this is just the rule of atomic. It doesn't mean you always have to use three. But when you are in doubt, default to three. And I showed you this example earlier. This is an example from President Obama's essay in wired. And notice that he picked exactly three reasons. He could have pick fewer or more, but he defaulted to three. Okay, one more example. I just want to point out that sometimes what follows after the colon is itself an independent clause. That is a complete sentence. And this looks a lot like when we used a semicolon. We have a situation where on both sides of the punctuation mark, we have a full independent clause. But there is a subtle difference. If you use a colon, you are intending for the second independent clause to amplify or build on the first. So take the example here. Companies use Marsh for the same reason that home sellers use real estate agents. The agent's knowledge and experience is supposed to help the client get the right deal at the right price. Notice that first clause sets up the second one. We are told that a reason is coming and then we're given the reason. A semicolon wouldn't really work here because we'd lose the setup. So just keep in mind that you can use a colon to setup a complete thought like this. And notice that many publications will actually capitalize the first word of that second clause to let the reader know that it's a complete sentence. So the is capitalized here. I see a lot of misuses of the colon so I just want to point some of these out. This example says two aspects of alcohol use are related to brain injury. As a factor associated with risk of an injury, such as a motor vehicle crash, and as a factor in TBI diagnosis, recovery, or survival. You can hear that this sounds funny. The problem is that aspects is a noun. The reader is told that they are about to get a list of aspects, which means The reader is expecting nouns to follow the colon. Instead, the reader gets prepositions, as. This is grammatically incorrect. To correct this, we need to use nouns after the colon. So we could say two aspects of alcohol use are related to brain injuries: its association with risk of injury and its post-injury influences on diagnosis, recovery and survival. Associations and influences are both nouns. Alright, another example of the misuse of the colon. This was actually from an email job announcement I received several years ago and I thought it was a bit funny, because they reversed what comes before and after the colon. The said in one project we have a nutritionist. A psychologist, statisticians, a computer specialists, and dietitians: a whole range of specialties. Well, of course, it's backwards. We want to set up the list with a colon and then have the list follow. So the correct way of writing this would be, in one project we have a whole range of specialties: a nutritionist, a psychologist, statisticians, a computer specialist, and dietitians. I think it's interesting that they have multiple statisticians and multiple dietitians but only one of the each of the others. I think this was a job advertisement for a statistician, actually. I'm going to end here with my favorite punctuation mark, which is the dash. You can use the dash to add emphasis or to insert an abrupt definition or description. You can essentially drop anything you want in the middle of the sentence by setting it off by dashes and your reader's okay with it. I think of it almost as get out of jail free card. Because you can get a way with a lot with a dash. You can get out of many jams because it so versatile. I will warn you however that you don't want to over use the dash. Because as I've mentioned, it's considered slightly less formal then the other punctuation marks. And if you over use it, it also losses its impact. I can remember when I was taking my first journalism class. The instructor told us it was okay to use the dash. And I thought this was just the greatest liberation to be able to write with a dash. So I was using dashes all over the place. And the first assignment I got back had this little note on the top telling me not to use dashes so liberally. So I learned quickly to not overuse the dash. But I do use it when I need it. Strunk and White say, a dash is a mark of separation stronger than a comma, less formal than a colon, and more relaxed than parentheses. And they do warn you to use a dash only when a more common mark of punctuation seems inadequate. In other words, reserve this tool for the really tough jobs. Here's a fun example of the dash. This was from an editorial by Thomas Friedman of the New York Times. He happens to be one of my favorite writers. And I think this example has one of the longest insertions of material that I've ever seen between two dashes so I wanted to share with you. It says, but my fellow Americans, whatever mix of motives led us to create an Electoral College majority for Donald Trump to become President -- and overlook his lack of preparation, His record of indecent personal behaviour, his madcap midnight tweeting, his casual lying about issues like millions of voters casting illegal votes in this election, the purveying of fake news by his national security advisor, his willingness to appoint Appoint climate change deniers without even getting a single briefing from the world's greatest climate scientists in the government he'll soon lead, and his cavalier dismissal of the CIA's concussions about Russian hacking of our election, have no doubt about one thing, we as a country have just done something incredibly reckless. This example illustrates just how amazing the dash is. I think it's wild that you can dump so much right into the middle of sentence, and it still works. It reads smoothly. I'll just point out that Freedman also used a colon at the end of this sentence to put emphasis on that last idea. I also want to point out that last week I told you not to put too much space between the subject of the sentence and the main verb. That's violated here. But it's okay because you can violate that if you use a dash. So the subject of this sentence is whatever mix of mood is. The verb, we don't get to until half, but the dash makes this okay. The reader can find the verb because it's just right after the dash. And so it works, it's an exception to the rule that I told you last week. Here's a few more examples, so here's an example of using the dash to add emphasis. The drugs did more than prevent new fat accumulation. They also triggered overweight mice to shed significant amounts of fat, up to half their body weight. Notice how the dash serves to emphasize the magnitude of the weight loss. It puts emphasis on the up to half their body weight, here's another example. Researchers who study shipworms say these mislabeled animals--they're clams, not worms--are actually a scientific treasure. We use the dash here to drop extra information right into the middle of the sentence just when we need it, to explain what we mean by mislabel. Using the dash here also kind of puts a spotlight on this cute little fact that shipworms worms are actually not worms. Now what would happen if I had used commas or parentheses rather than dashes in those two examples? Lets see. So if I'd used commas, the commas, if you use a comma you lose the emphasis, right. So on the first example, it would say they also triggered overweight mice to shed significant amounts of fat, up to half their body weight. It's a little clunky and it also takes the emphasis on the magnitude of the weight loss. That's what's important here, they lost a huge amount of weight. By using a comma, we lose the emphasis on that. The second example is simply not going to work with commas. It becomes a run on sentence, right? Because "they're clams not worms" is actually a full clause. Commas just won't work here. With parenthesis, you end up burying the information. So, in that first example, if we put the up to half the body weight in parenthesis, we're giving readers permission to skip over it. In other words, we're signaling that it's an unimportant factor, it's just half their body weight, it doesn't matter. So we really lose the emphasis on this critical finding, the size of the weight loss. With the second sentence, I actually think parenthesis really don't work here. Because if the readers skip that material, as they're allowed to do, they're not going to understand what we mean when we say that the animals are mislabeled. I think that's actually essential information. Okay, I have one more example to share with you. But I need to give you some background before I share this example so that you can appreciate the brilliance of this sentence. So I'm going to ask you to bear with me for a minute to indulge me and let me tell you a story. I am not a baseball fan. However, I grew up in New England, so I am a diehard Red Sox fan. And probably many of you know that at one point. The Red Sox were said to have a curse on them. That's because they went almost a century without winning a World Series. And not only that but they got within a hair's breadth of winning the World Series several times and then lost it on the silliest errors. So they were said to have a curse on them. I actually remember watching the 1986 World Series. The Red Sox were playing the Mets, and they were leading the Series three games to two. You only need to win four games to win the World Series, so they were one game away from winning. They needed to win the 6th game of the World Series. That game went into overtime, it went into a tenth inning. In the top of the tenth inning, the Red Sox scored 2 runs, so now they're leading. All they need to is to get the Mets out. And they get two outs, so they are now one out away from winning the World Series. The Mets batter comes up to the plate, hits a routine grounder. It should've been an easy out. But in an infamous error, the ball rolls through Bill Buckner's legs, they don't make the out, the Mets score three runs to win game six of the World Series. And the Mets go on to win the World Series, and everybody took this as proof of the curse. Now, fast forward to the year 2004. In 2004, the Red Sox finally did win the World Series. After a 86 year dry spell, and they did it in dramatic fashion. They were down three games to the Yankees in the American League series and you have to win the American League series to make it to the World Series. But they came back and won four games in a row against the Yankees to make the World Series. And then, they won the first three games of the World Series against the Cardinals. So now, it's the fourth game of the World Series. All they have to do is to win this game and they will win the World Series. We get to the ninth inning. The Red Sox are leading. They make two outs on the other team. So now they are one out away from winning the World Series. Well of course at this point everybody is waiting for the other shoe to drop. They are just waiting for the curse to rear its head. So the Cardinal's batter comes up, hits a routine grounder to the pitcher. The pitcher scoops up the ball, and normally in this situation the pitcher simply would have thrown the ball to the first baseman and made the out. It's a pretty simple play. But the pitcher knows the whole history of the Red Sox and he is not taking any chances. He's afraid that if he throws the ball to the first baseman, something wild is going to happen and they're not going to get the out. So he trots right up to the first baseman and gets as close as he can to him. And does this little underhand toss to practically put the baseball into the first baseman's glove. He is not taking any chances that something is going to get messed up. They do get the out, the Red Sox win the World Series. But that moment, when the pitcher decides that he has to go all the way up to the first baseman and practically hand him the ball, that moment encapsulated the entire history of the Red Sox and the entire ethos of the Red Sox. And so that's the set up for this example I'm going to present to you now. So the sentence says, Baseball is the only game that's played every day, which is why its season often seems endless, right up to the inning and the out-the little toss over to first base-when, wow, it ends. That little toss over to first base that the author is talking about here, that's the image of the pitcher walking up to the first baseman and practically handing him the ball. And that is such a powerful image because of everything that it says about the history of the Red Sox. And it stuck in there between two dashes, which again just shows how amazing the dash is. I don't usually give exact citations for the examples I use, but today, since most of the examples I was using were examples of good writing, of good use of punctuation, I just want to acknowledge the various authors from which I pulled those examples here.