Time Schema in Chinese (Tuesday, April 29, 2008)

In "Verbs and Times", Zeno Vendler asserts that there are distinctions between verb phrases, relative to factors other than simple tense, and offers a time schema to categorize these factors. It is interesting to look at how this is handled in a language like Chinese, which treats verbs quite differently than English. In particular, Chinese has specific particles called "imperfectives" to mark the aspect of a sentence. These imperfectives are 着(zhe), which indicates a static state, and 正在(zhèngzài), which indicates a continuous dynamic event. By grammatical convention, "zhèngzài" precedes the verb, and "zhe" typically follows the verb.

For example, let us consider the two sentences "I am hanging up the painting." and "The painting is hanging on the wall." The first sentence indicates a continuous dynamic event and is expressed by 我正在挂一幅画, roughly "I (am in the process of) hang(ing) the painting." The second sentence is a static state, expressed by 墙上挂一幅画, roughly "The wall hangs (in a passive sort of way) the painting." The sentences are structurally similar, using a subject, the verb "hang", and the object "the painting". The only thing that tells us what is actually going on, is the aspect marker, which tells us whether the object is undergoing any change.

In English, we seem to be concerned with whether something is "happening" or not, and divide "activities" and "accomplishments" from "states" and "achievements" because the first two involve "doing something", while the second two do not. In Chinese, it seems that the distinction has more to do with whether or not the object of the verb is undergoing any change in status.

The phrase 我吃 ("I eat") can be used for "I am eating" or "I was eating" or "I do eat", without any distinction. The meaning in that case is totally dependent on context. In fact, it is possible to say 我吃着一个苹果, ("I am eating an apple"), which treats the verb "to eat" as a continuous state, because all throughout the action, there is no change to the apple. That is, the status of the apple is "it is being eaten". This is analogous to the painting hanging on the wall, while in English there would be no such analogy.

Considering these examples, it seems likely that Chinese would develop a different logical time schema than that described for English by Vendler, with an emphasis on the change of state of the object, rather than on the activity of the subject.


"Chinese Grammar" http://en.wikipedia.org/wiki/Chinese_grammar. Accessed on 28 April, 2008.

Lu, Yanyan. Personal Interview. 25 April, 2008.

Vendler, Zeno. "Verbs and Times." The Philosophical Review, Vol. 66, No. 2. (Apr., 1957), pp. 143-160.

—Brian (04/29/2008 10:00 AM)

Social Distance Inversion (Tuesday, April 22, 2008)

Brown and Levinson discuss politeness in terms of minimizing threats to face in order to retain the cooperation of the addressee in an interaction. They state that a speaker will weigh the cost of a Face Threatening Action (FTA) based on his perceived social distance from the addressee, and that in general, he will not choose a strategy that minimizes risk to face more than is necessary to retain the addressee's cooperation. It seems that a corollary to this principle might be that a speaker may choose a higher cost FTA in order to elevate himself relative to the addressee in terms of social distance, and indicate that the speaker is coming from a position of strength.

For example, the social distance between a young panhandler and a passing business executive is quite great, and under usual circumstances, the panhandler would try his best to minimize the executive's loss of face when begging for money. However, if the young panhandler were so inclined, he might phrase his request in a way that implies a threat (of harm, of inconvenience, or whatever), elevating his position of power above the business executive. Even though their relative positions are unchanged, the panhandler can perform an FTA to attempt to invert their positions.

In another example, if two business executives are engaged in a negotiation, and one is negotiating from a weaker position, he could perform an FTA in an attempt to assert dominance and bluff himself into a position of power (as perceived by the other executive).

So it seems that while an actor's respect of face derives from his perception of social distance, he may also use a lack of respect of face in order to influence the addressee's perception of their social distance.


Brown, P. and S. Levinson. "Politeness." Cambridge University Press.

—Brian (04/22/2008 10:00 AM)

On Implied Context in Conversation (Tuesday, April 8, 2008)

In human conversation, it is necessary to be brief, while still effectively communicating an idea (Grice). This consequently leads to conversations that leave out a great deal of information, for which each participant will take for granted that the other participant is aware. If this context could not be assumed by the participants, conversation would resemble Tolkien's Ents, where the name for an object encompasses that object's complete history. While this may work in a fictional world, it would be impossible for humans, because even a simple conversation would last far beyond the relevancy of the ideas being communicated. This could lead us to ask how we determine what information may be left out of the conversation. However, considering that the quantity of information included in any conversation is vastly dwarfed by the context omitted, it seems that it might be better to start from nothing, and ask what information should be included.

Let us describe a subset of human knowledge as a collection of experiences and the relationships between them. It seems that conversation is an effort to share that collection of experiences and relationships with the other parties of the conversation. For example, take a simple conversation where John says, "I went to Dairy Queen," and Fred replies, "Oh, what flavor did you get?" Some of the experiences they share include the nature of food, specifically ice cream, and of shops that sell it, and that you can go to them, and so on. In John's collection of experiences, there is a link between one particular visit to Dairy Queen and a particular flavor of ice cream. Fred's collection of experience before the conversation does not include a link between John and the visit in question. John's utterance serves to provide Fred with that connection, so that following it, they share the knowledge that John visited Dairy Queen. Because of Fred's own experiences, he realizes that there is an opportunity for a connection between that visit and the flavor of ice cream had, and for whatever reason, asks a question for which he expects the answer to provide that additional connection.

In fact, it seems that most conversations are of a give-and-take nature that comprise a negotiation to establish connections between shared experiences. If John had instead said, "I went to Tom's place," and Fred is unaware of the fact that Tom's Place is a restaurant, he is more likely to ask, "Who is Tom?" rather than "What did you get?" It is necessary to establish that shared context, before additional connections may be made. In this example, the name "Tom's Place" isn't bound to any specific idea for Fred, and so the connection between John and that place holds little value. John's explanation of the restaurant serves to build those connections in Fred's mind. Following a successful conversation, both parties should share a similar collection of information about experiences and connections between them for the subjects of the conversation.

In that light, it seems that the missing information in conversation is not left out, but rather that the included information is chosen specifically to establish connections that previously did not exist and that the conversation itself consists of a negotiation to ensure that the context is sufficiently shared.


Grice, H.P. "Logic and Conversation." 1968 Harvard University Press.

—Brian (04/08/2008 10:00 AM)

SCIP 1.1 Java Interface for Hokuyo URG-04LX Laser Sensor (Wednesday, February 20, 2008)

The Autonomous Robotics Lab at George Mason University has attained several Hokuyo URG-04LX laser range-finding sensors that provide significantly better performance and accuracy than the less expensive sonar arrays. The Hokuyo is generally controlled via a serial connection (or via a USB port, using the serial protocol). The serial protocol is described by the SCIP 1.1 Specification, available from Hokuyo.

Because most robotics researchers are generally more concerned with testing their algorithms than in getting bogged down with the hardware, I developed a Java API that implements the serial protocol specification for the device.


—Brian (02/20/2008 10:23 AM)

Harry Potter and the Quest for the Holy Grail (Monday, July 23, 2007)

An Examination of the Relationship between the Deathly Hallows and the Traditional Quest for the Holy Grail

While reading Harry Potter and the Deathly Hallows, I was struck by how familiar the symbology for the Hallows felt. The Hallows are three ancient relics attained or created by the Peverell brothers that give the holder some measure of control over death. The relics are the Elder Wand, a wand that cannot be defeated when wielded by its master; the Resurrection Stone, a stone that can summon a sort of reflection of a person, back from the dead; and the Cloak of Invisibility, which hides the wearer from sight.

This all sounded so familiar, and it felt like Grail mythology. After a bit of research, I think I have come up with the Grail analogues. The Elder Wand or "Wand of Destiny" is obviously related to the Lance of Longinus, the "Spear of Destiny", which grants power to its holder. Like the Dark Lord, and Grindelwald before him, the Lance of Longinus was sought, according to popular myth, by Hitler, and that his suicide was prompted by its loss.

The Stone's analogy isn't as easy to come by, but I believe that it represents an equivalent to the Holy Chalice. Like the Stone, the Chalice is represented by a circle, and has the property of restoring life.

And finally, the Cloak seems to be analogous to the Shroud of Turin, the relic believed to be the burial dressing of Jesus. Like the Cloak, the Shroud is supposedly endowed with the power of protection.

Also of interest, while the Deathly Hallows were associated with the Peverell brothers, the Chalice and the Lance were sought by Percival, one of Arthur's knights (and with some irony, the source of one of Dumbledore's middle names). Fascinating parallels. I imagine that more parallels exist, given Rowling's wonderful literacy, whether intentional or incidental, and that we will have much fun identifying them over the coming weeks and years. Drawing on these sorts of parallels gives the Potter story that much more grounding in "reality", and pulls us to it more than ever.

—Brian (07/23/2007 10:18 AM)

Gallons of Galleons: Money in the Harry Potter Universe (Friday, August 11, 2006)

For the millionth time, I am working my way through the Harry Potter series, and once again, I found myself asking about how much Harry Potter's fortune is actually worth, and by comparison, the worth of the Weasley family's small savings. My research initially led me to the Harry Potter Lexicon article on Money, which lays out the basics. To quote Hagrid: "The gold ones are Galleons. Seventeen silver Sickles to a Galleon and twenty-nine Knuts to a Sickle, it's easy enough."

The next question is of course exchange rates. While it's not explicitly stated, it seems that the assumption is a fixed rate of exchange between British Pounds and Gold Galleons — five Pounds to the Galleon. Currently, that means that there are roughly $9.50 (American) to the Galleon.

The Lexicon states that "while wizard money seems to be made from actual precious metals, it also seems to have some sort of magic in it which makes it lighter than normal", as a way to explain how Harry is able to easily carry a bag of a thousand Galleons. I disagree entirely. I submit that like most modern money, the Wizarding coins contain some amount of precious metal — either in plating, as part of an alloy, or as a slug that is itself plated.

The fact is, even a small coin weighs at least five grams, or about one sixth of an ounce (Troy) of gold. Gold is currently worth over $600 an ounce. That means that a small coin made entirely of gold (without any magic at all) would be worth closer to $100 — ten times the actual value. And we know that the Wizarding world values gold, as our famed alchemist, Nicholas Flamel, claimed the ability to turn lead into gold as one of the main uses for the priceless Philosopher's Stone.

Therefore, at $634 per ounce for gold, and about 31 grams per Troy ounce, a Gold Galleon would contain less then one half gram of actual gold. Silver is currently priced at $12 per ounce, and at seventeen Sickles to the Galleon, a Sickle is worth about $0.50, and would contain about 1.3 grams of pure silver. And finally, bronze, which is basically worthless at $1.50 per pound, or about $0.10 an ounce. Therefore, considering twenty-nine Knuts to a Sickle, a Bronze Knut is worth a bit less than two cents, which would require about five grams of bronze.

For a bit of reference, I looked on the US Mint site, to get the specifications on modern American coins. A Golden Dollar (which contains not even a microgram of real gold) weighs 8.1 grams, while a Quarter weighs in at 5.67 grams. According to the Mint's site, a 1000-coin bag of Quarters weighs 13.42 pounds. We could assume that a bag of Gold Galleons weighs up to 20 pounds — any more than that and Harry probably wouldn't enjoy carrying it.

Either way, a Gold Galleon would be less than ten percent real gold by mass, a Silver Sickle would be around twenty-five percent silver by mass, and at five grams, a Bronze Knut could actually be worth its weight in bronze.

—Brian (08/11/2006 8:43 PM)

Brian's Own Harry Potter Conspiracy Theories (Tuesday, December 6, 2005)

Well, I keep threatening to write my own version of Harry Potter 7, because I just can't wait until Ms. Rowling gets around to writing it. I have lots of interesting ideas, some of which are original, and some of which, I admit, I got from reading every word everyone has ever written about Harry Potter. If you haven't read all of the books released, until now, reading what follows could ruin it for you. And no, seeing the movies is not even remotely adequate.

Is Snape Good or Evil? (12/6/2005)

For many people, this is probably a silly question. After what Snape pulled in the closing pages of Half Blood Prince, many people finally believe what Harry has been thinking all along. There are, of course, many reasons to believe that Snape is evil — his background as a Death Eater, his close relationship with the Dark Lord, his making of the Unbreakable Vow, his general unpleasantness with Harry, and of course the cold-blooded murder of Albus Dumbledore. However... there are also a number of counter arguments that have been presented over the last months. Snape supporters are quick to point out that Snape could have killed Harry at any time, and in fact has saved Harry (and other members of the Order) on several occasions. They point out that there must be something that Dumbledore knows that no one else does.

I submit that this is probably true. Snape, by his own admission, spun a tale of deep remorse to gain Dumbledore's trust. We know that his remorse was about the Dark Lord's interpretation of the prophecy. But why the sudden change of heart? His detest for James Potter is well documented.

I hypothesize that Snape was secretly in love with Lily Potter. The latest book has revealed that they had much in common. Potions and their Half-Blood heritage, in particular. We saw that Lily was one of the few people to come to Snape's defense. And while we saw Snape respond negatively to her help, we know that boys mature — James was being a bit of a twit then, too. James settled down, and Snape fell in love. And we know from an interview with Ms. Rowling that Lily was a bit like the Ginny of her year — very popular with the boys. So it isn't unlikely that Snape had a secret love for Lily.

So why would Snape betray her to the Dark Lord? In an interview I read recently, an astute observer asked Ms. Rowling why the Dark Lord gave Lily a chance to live, if she would only surrender Harry, and asked further if the Dark Lord really would have spared her. Ms. Rowling said that he would indeed have spared her, and that the "why" was a very interesting question. I hypothesize that Snape bargained with the Dark Lord for Lily's life, perhaps feeling he could comfort her in her loss of husband and child, and maybe convince her to start a new life with him.

So many Snape supporters would agree that this is precisely the sort of circumstances that would send him straight to Dumbledore. They explain away Snape's behaviour as it is explained away in the book, except for the murder of Dumbledore, which of course has not yet been explained. The prevailing theory of Snape supporters seems to be that Dumbledore and Snape had agreed upon this end in advance, and that Dumbledore asked Snape to kill him, in order to save Draco, and to once and for all convince the Death Eaters that Snape was truly one of them. And that no harm was done, because Dumbledore was dying anyway, as a result of the potion in the cave.

I would like to offer another alternative. The Slytherin alternative. Snape is neither good, nor evil. Merely a man seeking an end. And that end is revenge upon the Dark Lord for killing Lily. To exact this revenge, he knew he had to remain close to the Dark Lord, but at the same time, covering all angles, he allied himself with the one man who was most likely to defeat the Dark Lord — Dumbledore. Snape has no true allegiance to either side. His one goal is the defeat of the Dark Lord, by any means possible.

And besides, what true allegiance could he have to the Death Eaters? While he fancies the Dark Arts, he realizes that blood purity is nonsense. And the Death Eaters would destroy him if they knew his background. But Snape has patience — he realizes that the Dark Lord has protected himself using powerful magic, but I don't think he's yet discovered what Dumbledore and Harry know. Snape knows that he cannot simply kill the Dark Lord.

I have not yet decided what will be revealed in Book 7. Harry has a lot of growing up to do before he can take on Snape. It's unfortunate that Harry is motivated by revenge — I don't believe that Dumbledore would approve. More musings will of course follow.

—Brian (12/06/2005 11:00 AM)

Geographical Thoughts on Zimbabwe (Tuesday, May 11, 2004)

Geography Final Paper

"You just went to the post office in order to pick up a certified letter your boss is opening a new branch in Harare, the capital of Zimbabwe, and he offers you the opportunity to become the manager. What are your geographical thoughts about moving there?"

Zimbabwe is a South African nation located between South Africa and Zambia. It's capital, Harare is home to about one third of the nearly twelve million citizens (Rowntree 2003). It is a poor nation, whose politics are filled with trouble, and whose economy has been moving backwards. While there may be some good reasons to accept a position as manager of the new Harare branch, the problems that plague Zimbabwe will far outweigh them for a long time to come.

One key aspect to a branch in Harare is that with an average annual income of less than $600, it would be very inexpensive to staff with the best local employees at rates much higher than they could get from a locally owned company. Furthermore, this extremely low average income would mean that a manager like me could afford a life of relative luxury, including house staff (Rowntree 2003). Despite the poverty of the region, a 91% literacy rate implies that even if no skilled locals could be found, they are sufficiently educated (at a minimal level) to allow effective training (CIA 2003).

Also, despite its age and relatively poor maintenance, the telecommunications infrastructure of Zimbabwe is available in Harare, and remains one of the most advanced systems in southern Africa. This would make Harare the logical choice to open a new branch. Likewise, with the official language being English, and Christianity being the primary non-native religion, American expatriates like me would be better able to adapt to the area than to other parts of the region. (CIA 2003)

Unfortunately, there are many problems that prevent me from taking advantage of the opportunities that might be present. Zimbabwe's head of state, President Mugabe has been in power in 1980 and has done many things to damage the viability of the Zimbabwe economy. Over the past several years, his policy of redistribution of land has destroyed commercial farming, costing nearly a half million jobs since 2000. Mugabe's involvement in a four year long war in the Democratic Republic of Congo cost Zimbabwe large amounts of money. These and other policies, including a history of violence against opponents of his regime, caused the IMF to suspend its support for Zimbabwe until it can better meet its budgetary goals. (CIA 2003)

Furthermore, as Zimbabwe is located on the border between tropical savanna and tropical steppe, it is prone to drought. This coupled, with the AIDS epidemic (the disease inflicts over one quarter of the population), does not allow for the stability necessary to run the branch of a western company (Rowntree 2003).

Therefore, despite some of the benefits that might come from a branch in Harare, it seems that at this point in time, the country is simply not stable enough to welcome branches of foreign companies. If the regime could be replaced and economic aide restored, and the AIDS epidemic brought better under control, the existing benefits could motivate me to accept a position at the new branch. Until that time, it simply would not work.


Rowntree, et al. Diversity Amid Globalization. Pages 222-242. 2003, Prentice Hall.
"Zimbabwe". CIA World Factbook. December 18, 2003. Accessed on May 10, 2004. <http://www.cia.gov/cia/publications/factbook/geos/zi.html>

—Brian (05/11/2004 12:03 PM)

Recipe Context is Abbreviation not Grammar (Thursday, April 22, 2004)

In "Recipe Context Null Objects in English", Massam and Roberge propose a set of rules for leaving out objects in what they call a "recipe context". It seems that rather than a new grammar, the recipe context is simply an abbreviated form of the English imperative structure that has come into popular use.

They give examples that are meant to demonstrate special handling of different sorts of verbs, such as (1), to show that perception verbs do not allow the object to be omitted.

(1) Put pan over high heat and add water. *See/*Hear ___ boil before adding other ingredients.

However, even if you do not omit the object, the imperative does not make a great deal of sense, as in (2). Instead, the recipe writer would say something like (3).

(2) Put pan over high heat and add water. *See/*Hear it boil before adding other ingredients.
(3) Put pan over high heat and add water. Let ___ boil before adding other ingredients.

They also provide the example shown in (4) to indicate that the EO can also serve as the antecedent of a reflexive, which is true, but only because the empty object is missing due to abbreviation, not due to actual removal from the sentence.

(4) Set out ___ on tray PRO to be served later.

They provide a number of examples where they try to remove objects from more complex sentences and are unable to do so, as in (5) and (6). It seems that these would be grammatically acceptable (particularly (6)), however they violate the convention of simple imperatives for writing recipes - these would appear in a terse cookbook even if they included the missing objects.

(5) Put cake in oven. *Expect ___ to be done half an hour later.
(6) *You must beat ___ well and cook ___ for 5 minutes.

In conclusion, it makes sense that the grammar used when writing recipes is basically the same as conventional English, except that it can be abbreviated by removing objects in places where they are understood. Objects cannot be easily removed from more complex sentences, or sentences that do not easily fit within the context of a recipe. In these cases, the recipe returns to narrative and uses conventional English.


Massam, Diane, and Yves Roberge. "On Recipe Context Null Objects in English". 1989. Linguistic Inquiry 20.1 pp 135-139.

—Brian (04/22/2004 10:00 AM)

Monte Carlo simulations in the RPμ ensemble (Monday, March 31, 1997)

This is the abstract for the paper I presented at the 1997 March Meeting of the American Physical Society in Kansas City. This text is taken from the official program listing from that meeting.

Graphical version | Text version

Session M11 - Quantum Monte Carlo.
MIXED session, Thursday morning, March 20
Room 1202B, Conv. Center

[M11.07] Monte Carlo simulations in the RPμ ensemble

M. Karimi, B. Ziman, J. Matolyak (Physics Department, Indiana University of PA), T. Kaplan, M. Mostoller (Solid State Division, Oak Ridge National Lab.)

The usual way of calculating the chemical potential is to do grand canonical ensemble (TVμ) Monte Carlo (MC) simulations, where T, V, and μ are the fixed temperature, volume, and chemical potential. To calculate the chemical potential at zero pressure and a temperature T requires several MC runs at fixed T, V, and different μ to determine μ(P). The value of μ(0) for this T is found by extrapolation of μ(P) to zero pressure. RPμ MC, where R is an energy, was recently developed by Ray et al.(J. Ray and R. Wolf, J. Chem. Phys. 98, 2263 (1993).) and applied successfully to liquid palladium. The calculation of μ at P=0 and a given T can be carried out with a single MC run in the RPμ ensemble (as compared to several runs in the TVμ ensemble). This new technique will be employed to calculate the chemical potentials of liquid and solid silicon modeled with the Stillinger-Weber (SW) potential as a function of temperature. The melting point of the SW Si potential will be estimated using the condition μS = μL.

—Brian (03/31/1997 10:00 AM)