Oil

Next, Abraham asked Zimran to search for more oil.

The third son of the old man followed the footsteps of Issac and returned to the forest. Instead of digging, he picked up the shiny stones left by his brother and brought them back to Abraham.

"Why! They are diamonds! You smart boy!" Abraham nodded.

The old man then sent Jokshan to try.

The fourth son headed north-east and, a few months later, reached a no-man's-land. Without the good fortune of Zimran, Jokshan had to dig for himself. Nonetheless, after several weeks of painstaking exertion, no trace of oil could be seen. However, he found a good many stones - no, not the shiny ones that his brother Isaac had carelessly threw away. He tried again and again to see if he could make use of this nondescript finding.

At last, he found that the stones could burn.

He brought them back to his father.

"Good lord. You find a coal mine! Clever boy." Abraham said approvingly.

Sons

Abraham had eight sons.

He sent Ishmael to search for oil. The eldest son travelled south-east for a short distance and reached a desert. He drilled lightly and, in no time, liquid gold gushed out from the ground. He went back and told his father what happened.

"Good boy." Abraham said.

In the next morning, the old man asked Isaac to search for more oil.

The second son headed south-west, and, after a few weeks, found a forest by a long river. With the experience of his elder brother, Isaac was all skillful in drilling - but he found no petroleum. Instead, he dug out some hard and shiny stones. He threw them off, shook his head, returned to Abraham and told the story to his father.

"What a silly boy!" Abraham sighed.

(To be continued.)

Scrubs

A hot topic recently amongst our students is whether they could wear their student uniform (so-called medical scrubs) outside the hospital. A little acquaintance of mine is certainly touched (at the group c nerve fibers) and makes a lengthy open comment (see https://www.facebook.com/MedicSecrets, entry #459).

I must say I agree entirely with his argument. Infection control is an issue but not a critical one. Otherwise we would all have to change our clothes before and after going to work (be they medical scrubs or not) - which was what we did during the time of SARS. After all, the scrubs of our students (especially those junior ones) could not be very contaminated - how often do you think they really contact genuine patients?

However, I would like to see the phenomenon from another angle:

You can find many people wearing the football jersey of FC Barcelona or Real Madrid in the street. Some of them, however, have such a protuberant tummy that they would have difficulty to make their shoelace. A considerable proportion of others would be gasping to death after joining a football match for 5 minutes.

On the other hand, have you ever seen Lionel Messi or Cristiano Ronaldo wearing their own jersey to the pub after the national derby?

Present

Believe it or not, as a primary one student, Euterpe was recently asked to give a short speech to her class. Well, it is kind of a English project. Each and every one in her class takes turn to prepare a short speech (with their parents, of course) on the topic assigned and then to give the talk in from of their classmates.

The topic of Euterpe is A Present For Mum. For obvious reasons, I wrote the script with her.

Here you go.

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I want to give a present to my mum. It is about Christmas and I want to make her happy.

What present should I give?

My mum loves reading but we can borrow from the library.
My mum loves music but playing piano is too difficult for me.
My mum loves flowers but carnation is for Mother's Day.
My mum loves Candy Crush but it is not good for her teeth.
My mum loves travelling but she has to stay for exam with me.
My mum loves sleeping but I cannot send her a good dream.

I would present myself as a good girl to her because the most she loves is me.

Overqualified

You may ask: Is my Nexus good?

Maybe to your surprise, but, the scientific answer is I don't know.

To me, the new tablet is nothing more than a handy pile of books and journals and a small note pad, used mostly for my reading of PDFs and sometimes Words documents, with occasional notes to jot down for my flight of ideas. I hardly ever use it for internet search, not to say complicated computations or playing videos. In other words, there is actually no need to have the most advanced version of Android Jelly Bean as the operating system, or a quad-core CPU, or 2 GB RAM, or a screen of over 300 ppi, or stereo speakers with surround sound. All of these are cutting edge technology, but my basic needs are humble.

Nonetheless, I fall into the usual trap. When I consider which model to buy, the new version is almost always preferred. For example, the first generation Nexus is still around. It is around 40% cheaper, and probably serve my purposes equally well - but I still choose the new version released this July.

PS. The first generation of this tablet is, by all standard, overqualified for my requirement. I'm afraid that's a general phenomenon of the computer and electronic industry.

A computer could be no more intelligent than the man who uses it.

Nexus

I end up buying a second generation Google Nexus 7 from a local on-line store.

When I come to think about it, the process of buying is in itself remarkable. To cut the long story short, I set off with a decision to choose one of the common mini-tablets with a screen of 7 to 8 inches. Basically, there are four on the list: iPad mini, Samsung Notes, Nexus, and Kindle Fire; each has their own edges as well as problems.

But, rather than going to one of the chain stores for electronic devices and listen to what the salesperson say, I search from the internet to compare their technical specifications and details. In addition, I look up the YouTuble - there are dozens of videos that compare one device versus another, and many more that talk about the tips and tricks of using each of them. The final choice of Nexus is, therefore, a calm and careful decision. To use the jargon of psychologist, the experience of purchasing is far much better than going to a flesh-and-blood store in person.

Our shopping behaviour has changed - and I come to realize why Tmall is so successful.

Tablet

I bought a tablet recently.

The story goes like this: In the past two years I was using the good old traditional Kindle as my electronic reader (see http://ccszeto.blogspot.hk/2011/11/kindle.html), and I read most of my stuff with this handy gadget from Jeff Bezos - journal articles, leisure books, and comfort readings. Although it has no touch screen and practically no internet connection capability, the device is robust and durable. Charge it once and the battery is good enough for 3 to 4 weeks.

But, in the past three months or so, I was increasingly aware of the need to have something new. To begin with, it is not very convenient to read PDF in Kindle, and, if you read a journal article as HTML file, you lose many of the figures. More so, the screen is rather dim and difficult to read when there is little light.

I must say my first solution to all these problems was to rely on my cell phone. It has a very user-friendly apps to connect with Kindle, and, since I now put all journal articles to read in my Google drive, I could access them anywhere. The screen is small, but not uncomfortably so.

The problem is its battery is prohibitive - it doesn't last even for a single day use.

See http://ccszeto.blogspot.hk/2013/03/samsung.html

Competition

Discerning visitors may note that I have neglected a critical factor when I talk about who should be admitted to the medical school.

To put it simply, when there are two competing schools, the consideration becomes more tricky.

You may think we should not worry too much about what happen on the other side of the harbour. As long as we do our best and recruit students whom we think would become good doctors, we would have done a good job. Unfortunately, as I mentioned half a dozen of times, the standard of our graduates depends very little on how well we teach them, but almost entirely on the underlying quality of themselves.

And, the recent development is, if one medical school announce they are going to train up budding leaders of the field, how could the friendly counterpart declare they would accept and train up enthusiastic mediocre as followers?

PS. From the society point of view, it is obvious that we need just a handful of leaders but a whole lot more followers. The sobering truth is, it is against the interest of the two medical schools to direct their effort away from the few high fliers.

Character

At this point, you may think we should follow the Nobel winner of economics and design for the admission interview a structured script that focuses on standardized factual questions for the assessment of personality trait.

But that wouldn’t work. On one hand, senior professors would never agree to conduct admission interview purely for fact collection – and leave the judgement to the central administration. More importantly, we actually do not know for sure what personality traits make a good doctor.

You may be surprised and say, “Aren’t we aiming for applicants who are enthusiastic and eager to help the sick people?”

Yes and no. These are desirable characters but they are in abundant supply. What we really need are youngsters who are willing to take up an extra call when there is an urgent need, those who are willing to be the fifth assistant of a prolonged ultra-major surgical operation from which he could learn nothing, those who could continue to do the ward round when he has a post-nasal drip or ulcer pain, those who are wiling to complete the diagnosis coding or medical report despite they have never seen the patient, as well as those who could stand the temptation and remain enthusiastic ten or twenty years later.

As the Finagel’s Law states:
The data we have are not the data we want.
The data we want are not the data we need.
The data we need are not available.

Interview

You may argue, “We should put more weight on the admission interview. A comprehensive face-to-face assessment by an expert would not only give insight to the humanistic character of an applicant, it may also provide supplementary information about their intellectual capability which the result of open examination does not reveal.”

Very true – if we have the right persons and format.

You see? Not only are there dramatic inter-individual variations (or, actually bias) in the content of interview, professors who do the admission interview are merely experts in clinical medicine (or, nothing personal, even worse, basic science) – most of them have little experience in conducting an admission interview. (How could they be if they only spend a few hours each year on this matter that has little in common with their everyday work?)

And, it is both common sense and evidence-based conclusion that conventional interview with open-ended questions is an unreliable method for the determination of personality trait or prediction of subsequent performance.

Again, go read Daniel Kahneman’s Thinking, Fast and Slow.

Assessment

I’m sure you notice the flaw of my discussion yesterday.

Exactly – there’s no reliable assessment of the two domains that of our applicants.

To be slightly more specific, the correlation between the intellectual capability of the applicants and their performance in open examination (be it DSE, IB, or any other) is modest, and there is no way to test their enthusiasm or humanistic quality. The result is inevitable: Medical schools will have to neglect the heart and focus on the brain of an applicant, and, as pointed out by Daniel Kahneman’s rule of WYSIATI (what you see is all there is), only the result of public examinations could be considered.

You may ask: How about the admission interview?

Unfortunately, the interview serves, by and large, a symbolic function rather than having any pragmatic value. To say the least, the two medical schools are essentially using the interview as a tool of screening out – in order to eliminate applicants with outstanding performance in the examination but overt untreated psychiatric diseases (vacancies are reserved in the headquarters).

Factors

To begin with, let's take aside emotional factors and assume we have reliable means to assess our applicants, the question at hand is a generic one on decision making.

It goes like this: When there are two (or more) independent factors to consider (in this case, the intellectual capability and the degree of enthusiasm) and the outcome is a binary one (that is, accept an applicant or not), how should we arrive at the decision?

Yes, you guess that much. The traditional way is to give an overall mark by combining the scores on both aspects, usually multiplied with some predefined weighting for each of them.

But, is it the ideal method? Maybe not. With such a system, you would expect the successful applicants are those who do reasonably well on both aspects. If you look at them as a whole, they would be a homogeneous lot of mediocre.

How to get around with this problem? Some tried the two-by-two matrix system with proportional allocation. For example (a really hypothetical one), a medical school could accept one third of the applicants who have the highest combined score, another third who score the highest in the intellectual capability test (as long as they achieve a certain minimum standard in the other component), and the final third who are top on the enthusiastic test (and, once again, satisfy the basic requirement of capability).

Sounds perfect, eh?

Yes, in the ivory tower.

PS. It is interesting to consider what minimal standard of enthusiasm should we ask for from those capable intellectual high fliers. My personal opinion is - low, very low.

Minimum

You may argue, “Yes, it is true that we must take the ability of the applicant into consideration. However, is it all that important to admit only the crème de la crème of the youngsters? Or, isn’t it reasonable to admit schoolchildren who are really enthusiastic and are able enough to become doctors – although they may not be the most high flying few?”

That's a perfectly correct statement, but a few questions remain.

The first, and the more easy one, is this: Take aside the humanistic quality, what is the minimal intellectual capability that is needed so that one could study medicine?

Not low, of course. But neither is it incredibly high. In my experience, and I must declare I have some in this regard, anyone with an average intelligence could pass all examinations and graduate, sooner or later. (Alas, the really average ones may have a hard time for themselves - as well as their teachers!)

The second, but also more difficult consideration is: Should medical schools accept enthusiastic applicants with good enough but not-so-brilliant a capability?

Ability

I shall not discuss the political side of this matter. Frequent visitors of this site would know I explain my opinion on the general principles of recruiting medical students in a few occasions. There are two important points that I need to highlight:

• An enthusiastic and kind-hearted person is not necessarily a good doctor (if he is ignorant enough). 
• The quality of medical graduates depend very little on the teaching they receive, but, by and large, on their intrinsic capability.

For the first point, some of you may argue, “Knowledge and capability are important, but a good doctor must be eager to help and kind at heart. What good is there to have a clinician with superb skill but is only interested in making money?”

Translated to the language of logic, we mean humanistic characters are necessary conditions, but not sufficient conditions, for a good doctor.

Simple, eh?

The inevitable implication of this conclusion is we cannot admit all saints to the medical school – we must consider their ability.

Opinions

A recent hot topic within our circle is the competition for medical students between the two medical schools.

Instead of telling you what I think (which I'm afraid you may be quite sick of), let me show you some posts from Mark Zukerberg's country:

*****************************
"When I was reading all these news about the new "medic degrees" the two universities offering, I just remembered that I would not know if I wanted to become a doctor when I was 17/18 year-old, let alone a health policy-maker, a clinician-scientist and a medical lawyer. (of course there are people that are very determined about these things)... Why wouldn't you let students decide when they have been exposed to the fields and figured out what they actually like... If they want to, I don't really think it is that hard for a medical student/graduate to pursuit a degree in research/public health/law. And now, they are just trying to divide the cohort into different streams on the first day of medical school without good reasons..."

*****************************
"I don't understand why admission to medical schools becomes a competition. What are they looking for? Are they looking for high admission scores to boast of in front of parents, or are they looking for people devoted to the medical career? I just want to study medicine. Don't really care who is winning and where I am studying... Is there really a big difference? I doubt it."

*****************************
“做醫生除左要有心，能力一樣重要。醫科唔單只難入，即使你狀元成績入到嚟都唔代表你可以順利畢業。呢個世界唔係人人都做到醫生，入唔到既唔好質疑其他成績好過你既人有冇你幫人既心。”

*****************************
"我估計那個competition是指兩所醫學院在收生方面的競爭。醫科入學成績固然斐然；但是大學仍希望取錄最優等的學生，不但是因為考試成績能估算一個同學能完成整個醫學課程的能力，也希望畢業同學可以為大學發揮更大影響力。話雖如此，醫學院應確保課程教與學都具良好質素。當絕大多數醫學院學生由醫管局醫生指導，大學教授卻埋首研究，這是個合理的現象嗎？"

*****************************
"現時公開考試是否一個最好的制度去衡量一個人的能力，都是一個問題。這個考試中很低分的人，當然可能是能力比較低，做事懶惰，也可能是家庭沒有資源，加上學校環境惡劣，以致學生難以正常發展。如果你捐助他讀書，給他機會去讀好的學校，朋友圈子唔同，人都會唔同。
考試比較高分的朋友，我們都只是幸運而已，你覺得A和B, 5**和5*差距很多嗎? 未必。為什麼你有A/5**? 只是可能你遇上一個鬆手少少的考官，或者是一個很欣賞你思維的考官，所以你才拿下這個分數。
(這個test 可能很sensitive，但一點也不specific.)
在5**/5*的差距 同 做人的深度差距之間去衡量，我想這才是醫學院要思考的問題。 我們爭取最高成績的學生，只是因為成績是唯一比較客觀的指標，但有能力的人不代表他是最出色的人，有更多的成功要素是沒法衡量的，例如待人接物的態度，處世為人 等等... 醫學院不應只著眼在高分中的最高分那些人，而是想辦法找出有更多其他潛能或特質的學生。這些潛能同特質很可能比考試拿多一個A更重要。"

Practice

“That’s because, in the previous hospital, he was a specialist and doing only junior calls. And, you know, he’s kind of a slippery chap. Whenever there was a call for responsibility, he could always pass the task swiftly to someone else.”

“Yes…?”

“The advantage is his hands were clean and he hardly had any complication in the past. The down side is, unfortunately, in spite of his fellowship and certificates and impressive curriculum vitae, he never really masters the skill and sharpens his tools. When he was promoted to the new hospital, things changed. He is now the senior and has to shoulder the responsibility. Naturally, all his inadequacies come to the surface. After all, it doesn’t look good to be a third-call surgeon and cannot do a proper, say, right hemicolectomy. Unfortunately, forcing himself to do all these is too much a challenge to him.”

I nodded. That's the whole idea of training - ones should not just want to pass the examination, but to prepare confidently for the demanding task ahead.

Resign

Met L on my way home. In addition to many remarkable characters, he is also the lord of the grapevine.

“You know, WT just resigned.”

I know WT; he is a surgeon who was promoted from one hospital to another not too long ago.

“Alas, is he screwed up by his warrant trading, or is it because of a new exquisite apartment that he buys?” I smiled.

“Neither. He has a series of so-called unfortunate incidents in the past few months, and his boss is less than forgiving. In short, he is resigned – in an elegantly executed passive voice.”

“But, how could that happen? I mean, I don’t think I heard of any problem with his surgical technique in the past. Why on earth does he have so much trouble in the new hospital?” I was puzzled.

(To be continued.)

Trotter

A recent obituary that caught my attention is the death of Charlie Trotter.

For those who are not familiar with cookery, Trotter was an American Chef who owned the Michelin two-star restaurant Charlie Trotter’s in Chicago. He also appeared in the TV show The Kitchen Sessions with Charlie Trotter, which I first watched in 2005 and was immediately impressed by his orderly method and meticulous details.

“If there is reincarnation and Hercule Poirot turns into a cook, it must be him.” I said to myself.

Two years ago, I had the opportunity of staying in Chicago for a few days. I was almost courageous enough to book a table and dine alone at Charlie Trotter’s. In retrospect, that’s really a pity – the restaurant closed down last September.

Nonethless, to me, the famous chef survived by two cookbooks of his on my shelf: The Kitchen Sessions with Charlie Trotter and Charlie Trotter Cooks at Home.

RIP.

Balance

In a such question of life or death, why should we be affected by the wordings?

No, we should go back one step and ask: Is it merely the effect of framing?

The problem is, in the “peak-and-end” model, as well as the cold water immersion experiment, the parameter being assessed has only one dimension. A person suffers, and we assess how he values his suffering and makes decision – and same for enjoyment. But, in real life, we have both at the same time, and our decision on accepting a treatment depends on the balance of the two. As Daniel Kahneman points out, the factors are not put on the two sides of a balance and cross out each other.

Unfortunately, in the context of medical decision, Kahneman’s doctrine of loss-aversion does not hold either. (I must admit I am not aware of any experimental proof of my suggestion, but it seems consistent with what we observe everyday.) In general, people do not avoid loss (that is, suffering) even if the gain (pleasure or enjoyment) is minimal. The respiratory drive of many patients is not the degree of joy or excitement some time later, but an imprinted idea that could not be easily appreciated by an outsider (for example, graduation of one’s children, completion of a book, or conclusion of a lawsuit).

In Buddhism, we call that obsession (執念).

Frame

There is a critical flaw in my argument yesterday that may skip your eyes.

As Daniel Kahneman says, the decision really depends on how you phrase the question.

You see? Let’s imagine we ask a cancer patient the following question: Would you accept a treatment that would increase the maximal suffering for a while, have no effect on the terminal symptoms, and could slightly prolong your survival? If we use the “peak-and-end” model described yesterday to assess value, the expected answer would be NO.

But, we certainly agree that’s not the answer in real life.

Why? Because we are trapped in the wrong frame. If we begin by asking this: Would you accept a treatment that neither affects your maximal nor final pleasure, but could slightly prolong your survival? We could reply a logical YES.

Prolong

When I come to think of it, the ideas of Daniel Kahneman are not only applicable to economics and psychology; they challenge many of the common concepts that we hold for clinical medicine.

One notable example is the assessment of suffering. Kahneman's theory is simple: the subjectively experienced degree of suffering has nothing to do with the "area-under-the-curve" amount of pain or other unpleasant feelings, but is determined only by two factors: the maximum degree of suffering during that period, and the degree at the end of the period. In short, by and large, all that ends well feels well.

And, this phenomenon would make a whole lot of difference to the practice of palliative care. For example, the orthodoxical teaching is Do not prolong the suffering. But, if the duration is not a problem, a palliative treatment that prolongs a suffering life is, arguably, not undesirable as long as the finale is not that miserable. On the other hand, if, for example, a treatment of cancer can extend the survival by, say, 6 months, but, at the same time, induces a transient but intense adverse effect, then, assuming there is no change in the suffering before the eventual death, the treatment is valuable according to the traditional view, but it would not be welcome by the patient.

For obvious reasons this theory needs further testing in clinical setting. I must say the cold water immersion experiment presented by Daniel Kahneman is, from a physician's point of view, child's play. Patients may view suffering very differently when we talk about real diseases.

Think

My recent leisure reading is Daniel Kahneman’s Thining, Fast and Slow.

Daniel Kahneman is a winner of Nobel Prize in Economics, and, by and large, this book summarizes decades of his research.

Kahneman's general idea is simple: There are two systems – or, to be exact, two modes – of our thinking. One system is fast, instinctive and emotional, while the other is slow, logical, a laborious. I must say the idea is not new to me – it has been described in quite some detail in Daniel Goleman’s bestseller Emotional Intelligence – and, in fact, has a neuroanatomy basis (the archicortex of the hippocampus and limbic system versus the neocortex of the cerebral hemisphere). The brilliant contribution of Kahneman is, however, his work on how human beings make choices, especially on various aspects of cognitive bias and how we value benefit and risk.

My comment? Very simple. Before I finished with one-third of this book, I decided to read it again some time later - with a writing pad ready for taking notes.

Or, I dare say, it is not an honor of Daniel Kahneman to receive the Nobel Prize - it is the honor of the Prize to have such a recipient.

Everything

The meeting didn’t last forever, but what Mr. Greene said kept echoing in Franz’s mind. Later that evening, when the humble nerd was dragging his exhausted body home, he met Philo – a wise friend of his.

It goes without saying that Franz told his friend what he thought.

To the surprise of Franz, Philo was less than sympathetic, “Although the argument is bitter to the palate, it is, nevertheless, a logical conclusion.”

“How could that be?”

“My friend, it is a romantic idea to run a department store that sells everything. For example, if you think it is not good enough to have dedicated areas for women’s fashion and cosmetics, and a counter for electronic device – say, tablet – is necessary, is it good enough if it sells only iPad and leave out Samsung, Nexus, Kindle Fire, and so forth? You may have a specialty nominally, but you certainly could not cover every subspecialty.”

“That may be true,” Franz scratched his head. He couldn’t really tell whether his friend was speaking the truth or irony.

Difference

“The other way is to close down all teams that are not making money, with an aim to focus our effort on expanding the high flyer.” Mr. Greene said triumphantly.

Franz bite hard on his lips, so much so it bled. Yes, painful. My god, it’s not a dream!

“Sir, that’s not quite possible. We are running a department store. How could we tell our customers that we do not sell toys or lap top computers?” Albert raised his hand and said. He was the head of the toy corner. Franz nodded with approval.

“How couldn’t we?” The CEO sneered, “We are here to make money, not to take care of all the wish of everyone. It is the responsibility of our Minister of Commerce to make sure there are toy or computer stores around so that the need of London citizens are satisfied.

Franz was puzzled. The old Tobias Greene seemed entirely logical, but Franz didn’t feel right. If Debenham & Freebody sells nothing but women’s fashion and accessories, he could not imagine how this so-called department store is different from Esprit or Giordano.

Help

Franz shivered. He felt something was going to happen.

In a lightning speed Mr. Greene went through a handful of slides. The message was simple and clear: some are doing better than the others. Or, as Vilfredo Pareto predicted, 80% of the store’s profit came from 20% of the teams.

The CEO paused for a moment, cleared his throat, and then went on, “Guys, I’m sure the situation is obvious. Women’s fashion and cosmetics are making a good fortune, while toys and electronics aren’t getting anywhere. The problem is: What are we going to do about them? You know, there are two choices.”

Franz gasped. He fancied a good number of people in the room did the same.

“First, we can put more resource and effort to help the teams that are not doing so well…”

An uncomfortable silence filled the air.

“… but this is not the most cost-effective way of using our resources.”

Meeting

Franz took a deep breath before he pushed open the door of the conference room. There were already a few people sitting by the table, but, thank goodness, he was not late - and their CEO had not arrived.

After taking a seat as far from everyone as possible, Franz’s mind began wandering. He was summoned to this meeting no earlier than yesterday, and had no idea what is the purpose of gathering all team managers. He joined Debenham & Freebody for nearly 15 years and had served three CEOs, but he could not remember a single managerial meeting being held in this department store.

But, true, they had a new CEO now.

*******************
Franz’s daydreaming broke off when the door of the conference room sprang open and Mr. Tobias Greene – the new CEO – appeared.

“Ladies and gentlemen, I call you all to come to discuss a serious matter,” the CEO said when he swiftly moved to the center of the room and settle himself in the most comfortable chair, “We shall go through the sales of each and every team.”

(To be continued.)

Excess

While talking about the population growth of the Qing empire, some simple arithmetic may skip your eyes.

It goes like this: By growing Champa rice, the productivity of farmland doubled. In other words, twice as many people could be fed - but the number of farmer needed remained the same. What happened to the people in excess?

In other words, how did they make a living?

Simple. By industry.

That's why the handicraft industry of the Qing empire, notably porcelain and textiles, had such an explosive development during that time. Thanks to Christopher Columbus and Ferdinand Magellan, international trade became a booming business, and there was no shortage of overseas market. Silk, china and tea were all in great demand by the Europeans, and, since Chinese people didn't quite need any imported goods, the Qing empire was running an astronomical surplus for some decades.

Of course, the wind changed when tea and opium were extensively planted in India - the latter served no purpose except being exported to China for the exchange of silver.

And the rest is history.

Growth

I must say I should not be too excited with the historical record of China population, which you could easily find in the Wikipedia.

In short, the population of China fluctuated but remained around 50 to 100 million from the Tang (唐) dynasty to the beginning of the Qing (清) empire, but it shot up  in the subsequent 150 years and reached 400 million when Daoguang (道光) began his reign.

The obvious problem is why. In addition to the long period of stable society, most western scholars believe it was the result of introducing new crops from the Americas, including peanuts, potatoes and maize. Of course, as Chinese, we know these plants play relatively minor roles in our ordinary diet, and the extensive agricultural use of Champa rice (占城稻) was probably the main reason. This crop originates from Vietnam and was first sent to the Sung (宋) Emperor as a tribute gift from the Champa state of Vietnam. After centuries of adaptation and modification, Champa rice was gaining popularity amongst farmers because it is quick-maturing, drought resistant, and can allow two (occasionally three) harvests each year.

In other words, more land could be used for agricultural purpose, and the productivity doubles for any fixed area of farmland.

PS. The crops from the Americas, nevertheless, do play important roles. Potatoes and maize could grow in arid plateau and rugged mountains - places where rice could not survive. Peanuts, by the very nature of nitrogen fixing, greatly enriches the protein content of the ecosystem.

Weapon

My recent bedtime reading is Strategy, Tactics, and Weapons of the Medieval China (戰略戰術兵器事典：中國中古篇) .

Seriously this is not a book but, rather, a collection of monographs on the history of military science of China - by several Japanese scholars. I found it in Eslite during a trip to Taiwan last year and, as a lover of both weapons and history, it was impossible to resist the temptation of buying it.

Like all multi-author texts, some chapters are brilliantly written with gems here and there, while others are practically intellectual plagiarism. A considerable length of the book is used to discuss and compare the cavalry and infantry systems of the Middle Kingdom and Turks and Mongols. In my opinion, however, the most interesting piece of information appears towards the end of the book, in a table which summarized the population of the whole China at each dynasty.

Why should Japanese scholars have such a keen interest on all these?

Another

"A new church? Yes and no," the mayor tried to be evasive, "The problem is, Father, you have always been so placid and nothing seems to have been done."

"Alas, not competent in anything but competent in not having anything, not skillful in talking but skillful in not talking (無能事而能無事,不擅言而擅不言)," Father Brown murmured.

L apparently did catch what the priest said, "No, that's not what we ordinary people expect. The world has changed. After all, the church has received an astronomical funding from the village bursary. We need to see some work being done - for the hibernating Satan or whatever!"

"And therefore you ask someone to set up a new church. Is that what you mean?"

"That is certainly one option." A voice appeared behind Father Brown and L.

The two men turned to the voice. Professor Y was standing at the door.

The alternative scientist moved forward and continued, "You see? We know everything about devil and exorcism. All we need is money from the village coffers. If Mr. Mayor could redirect his budget for the church to me, I could either take over this church or set up a new one and get everything done."

The priest gasped, "My god. Is that the reason for you to appear in this village from the very beginning?"