The Paris Metro

Andrea and I recently returned from a ten-day vacation in Paris.  Everything about Paris impressed me, but one thing that I really felt was worth a blog in and of itself is the Paris Metro.

Metro is short for "Metropolitan" and is Paris' underground rail system (or "subway" as we would term it).  I've seen similar systems in other cities but nothing to match the Paris system.  It's amazing.  It's also incredibly clean, fast, and safe.

Part of what makes the Metro so convenient is the sheer number of lines and stations.  They say in Paris you are never more than 500 meters from a Metro station.  In my experience it was rarely more than a couple of blocks.  And once you enter a station and pay your way through the turnstiles you can now get to anywhere in Paris in a matter of minutes.

I bought a book before we left, "Discover Paris by Metro" which is a great book to have with you if you know how the system works.  It does not, unfortunately, explain the system at all.  So I thought I'd do that.

Paris is completely criss-crossed underground by subterranean rail lines; Fourteen of them as of this writing. When you descend into a Metro station typically that station will access one, two, or even more of them (most are just one).  There are trains running in both directions, named for the end of the line that they are headed for (each line has two ends, which are stations).  They don't use directions like "north" and "south" because the lines snake around the city in various directions.

For example: We were staying in an apartment near the "Porte de Vincennes" Metro station, which is on Line 1.  Line 1 runs from the "Chateau de Vincennes" station at one end across the city to the "La Defense" station at the other (the stations are named for nearby streets or points of interest).  So there are two platforms at our local station, one marked "1-La Defense" and another marked "1-Chateau de Vincennes".  There is also a map of line 1 on the wall (at the station and inside the trains).  If I know we want to get to the Louvre, and that its nearest Metro stop is "Palais Royale, Musee de Louvre", I can see that that's in the direction of "La Defense" from where we are, so we hop on that train and hop off at the station we want.

And I do mean "hop".  The trains run just about every two minutes so in general when you reach your platform you'll wait a very short time for the next train.

But let's say you want to go somewhere which cannot be reached by your local train.  Again, line 1 was the only line served by my local Metro station, but let's say we want to go to "Bir Hakeim" which is the closest station to the Eiffel Tower.  The "Bir Hakeim" station is on line 6, not line 1.

No problem.  You look at your Metro map (buy one, or there is one on the wall at every station) and find a station that serves both line 1 and 6.  There are two, "Nation" and "Charles deGaulle Etoile".  We pick the closest one and head that way.  When we get off at, say "Charles de Gaulle Etoile" there will be signs pointing us to the two different platforms each for lines 1, 2, and 6, because those three lines cross there.  We want 6, and so we pick the platform for the train going in the right direction for us, and get off at "Bir Kakeim".  But we never paid anything at our transfer station because once you are in the system you're good to go for as long and as many stops as you like.  When you leave the system then your ticket dies and you need another.

Alternatively, you can buy a weekly or monthly pass.  These are great because you just "scan in" at the turnstiles and you can go anywhere, anytime.  These passes also work on the buses, the surface light rail (the "Tram") and the trains (RER) to more remote areas like the airport and Versailles.  You "recharge" your pass for a Monday - Sunday period, online or using machines in the Metro stations.  There is also a clerk in every station to help you and most of them speak English.

The only other detail to consider is how many "zones" to make the pass valid for.  If you're just going to travel around Paris proper, buy zones 1-3.  If you're going outside Paris (Charles De Gaulle airport, Orly airport, Versailles) then buy zones 1-5.  Either way, it's an incredible deal.

You're probably thinking "yes, but how will I know the closest Metro station/line to a place I want to go?" That's where the book I mentioned above really shines.  There are sections for each line, explaining what is near each station as you go, and there is an index in the back where you can look up various attractions and it will tell you the line and station you want.  So if you know how the system works, the book fills in the rest.

One more resource you may find helpful is a metro planning site sponsored by the RATP, which is the rapid transit authority for Paris.  You put in any starting address and any destination and it will recommend the stations, trains, and changes to most efficiently get you there and even a little walking a map for the last bit when you arrive.  Here it is: http://www.ratp.fr/itineraires/en/ratp/recherche-avancee. Make sure to click on "EN" in the upper-left corner for directions in English.  (This site does not work very well in the US, so just use it once you get into Paris.)

The tool allows you to specify the fewest train changes, or the least amount of walking.  Choose the latter; the only thing about Americans in Paris is that you're going to get quite footsore.   Just walking through the Louvre will leave your feet throbbing.

Don't be intimidated if your route involves lots of train changes.  You won't wait much at all since the trains are so frequent.  If you get on the wrong train, or one in the wrong direction, just get off at the next stop and take the next train going the other way.  Once you get the hang of it, it really is child's play...  and the trains are so fast that it almost feels like you've got the transporter from Star Trek.  Enter at one station, emerge at another.

Don't rent a car in Paris. The traffic is terrible, many of the streets are quite narrow, and you'll just get frustrated.  Take the Metro. 

Gravity: How much of it is wrong, and why that's right

(Warning: Spoilers for "Gravity")

Alfonso Cuaron's magnificent film "Gravity" finally debuted last week.  I've been waiting for this event for years, having heard what he was attempting to do and having been totally blown away by his last film "Children of Men."  I was not disappointed.

Gravity is a masterpiece of film craft in every respect.  The effects are nothing short of breathtaking, the writing is crisp and compelling, and the performances are spot-on.  I did not realize what a brilliant actress Sandra Bullock was.  She really stands out, even though George Clooney is also performing at an extremely high level.

That said, the films physics (at least in terms of orbital mechanics) are completely wrong.  I think Cuaron knew this, chose to do it incorrectly, and that it was the right choice. 

Allow me to explain:

"Gravity" does not take place in zero-gravity, it takes place in free-fall.  Kowalsky and Stone are not in deep space, they are in orbit, where the gods of orbital mechanics make the rules.  They are extremely  odd rules.

In orbit, Earth's gravity is pulling you down constantly, but your forward momentum is pushing you away, at an angle.  The combination of this angular momentum with the gravity produces a balance that keeps you at a steady altitude above the earth and makes you feel and appear to be "weightless".  Even when the astronauts seem relatively motionless, they are hurtling around the earth at very high speed.  You cannot see this because they, and the shuttle, are moving together.

In orbit, your speed is your altitude, and your altitude is your speed.  If you increase your speed you move into a higher orbit, farther from the earth.  Decrease your speed, and the opposite happens, you drop into a lower orbit. The strange part comes from the fact that a higher orbit is a larger circle, and so you will take you longer to circle the earth.  In a lower orbit it takes you less time to complete that circle, because it is smaller.  So if you speed up, you don't increase your rate of orbit, you decrease it.

If you and I are in the same orbit, but you are 100km ahead of me and I want to catch up, I cannot do so by firing my thrusters forward.  If I do, I increase my speed and move myself into a higher orbit, farther from you.  Also, you will begin to creep away from me because you are in a lower orbit than I am.  No, to catch up with you I must fire my thrusters backwards, away from you, so I will slow down, drop into a lower, smaller obit, and then wait until I catch up with you and pass you a little.  Then, a bit ahead of you and below, I fire my thrusters again but this time to speed up, thus rising into your orbit for rendezvous.

This all assumes we are both in a standard equatorial orbit.  If one of us is orbiting at a different angle, then things get really complicated.

Rendezvous in orbit is really, really hard.  A major goal of the entire Gemini program was just to figure this out.  Buzz Aldrin (who landed on the moon with Neil Armstrong) got his PhD in just this problem, which is why many called him "Dr. Rendezvous".

I am sure Cuaron knows this, as he took years to prepare this film.  He also knew that if he filmed the real process of, say, Dr. Stone piloting her Soyuz to the Chinese space station by flying away from it, the visual result would make absolutely no sense to the audience.  Everything in orbit works backwards, and explaining this in a film would make for very dry, pointless exhibition.

This is a great example of the difference between verisimilitude on screen and "realism", which often does not work well as art.  It takes careful consideration to know when do to one versus the other.  All of the "three dimensional skating rink" maneuvers that Stone does while floating in the ISS, for example, are perfectly correct.  That works because the "floating astronaut" something we all understand now in terms of its visual language.

Again, I point this out not to criticize the film or the filmmakers, but to praise it and them.  The film gave me an absolutely real "feel" of being in space, even though I came to it knowing how the mechanics really work.  I was totally invested in the drama.  That's a master at work.

Whither Countries?

When Al Qaeda attacked us on 9/11, the immediate response was to mourn and attack.  The second response was to ask questions.  Why were we attacked, and what should we now do about it?

The "why", it was said, had to do with our military presence in places deemed sacred by Islamic extremists, like Saudi Arabia, and our strong alliance with Israel.  The "what to do" was pretty much a split between "we need to be stronger and fight back" and "we need to remove their motivation to attack us in the first place."

I was pretty much in the latter camp; not because I am overly dove-ish, but because it seemed to me that it would be difficult if not impossible to defeat an enemy that was diffuse, hidden, and motivated so strongly that its members are willing to die in order to harm us.  How, I thought, do you fight an enemy with tanks and bombs when that enemy is embedded in the civilian population?  If they are willing to die, then you can neither break their morale nor cause them to run in fear.  You would have to kill every single one of them, and they will be busy recruiting new members all the time.  In fact if you attack them where they are, in the midst of the innocent, then you will  simply create more hatred toward you, and inspire more terrorists.  You would be creating the enemy as you destroyed it, and you cannot win that way.

No, I thought, you have to remove their desire to act against you.

The recent bombings at the Boston Marathon have disturbed and sobered us all, but they have also called into question the notion that we can somehow become better actors in the world, and in so doing will remove the threat of terrorist attack.  Our best information is that these two terrorists came from Chechnya, and actually fled here due to religious and political persecution in their own country.

We have no bases in Chechnya.  As far as I know we have not done anything there, have not insulted any holy ground, nor buzzed them with drones, nor exploited their natural resources.  Their traditional beef is with Russia, and with forces within their own borders who are guilty of ethnic cleansing and other horrible atrocities.

I would not wish a terrorist attack on anyone, but why did these young men attack Boston?  Had they bombed Moscow or Grozny it would have been equally tragic, but it also would have a potentially logical link to the actions of the country whose citizens they attacked.  One could say "this is horrible."  One could also say "this is what motivated them."  Here, unless something we don't know about right now comes to light about the U.S.'s involvement in some kind of covert acts of oppression, we cannot say that.

I suspect they chose the Boston Marathon because it is very visible, very public, and a lot of people would be there in the open, and vulnerable.  I suspect they chose it because it was convenient; they were living there, had the resources to make the bombs locally, and did not have to infiltrate to plant them.

If this is true, then what does it mean?  We live in a world where you can tour Venice on your laptop in real time.  You can skype video chat with someone in the Sudan for free, as much and as long as you want.  You can enter a city you've never seen before, with no map, and be guided to anything with with your GPS at no charge.  The notion of "I am here and you are not" is gradually and inexorably fading away, and it may be that soon the notion of the country or nation state will be as antiquated as morse code.  Maybe it already is.

I suspect that writer Paddy Chaefsky was prescient when, in "Network", his character Arthur Jensen says:

"There are no nations. There are no peoples. There are no Russians.  There are no Arabs. There are no third worlds.  There is no West... There is no America.  There is no democracy.  There is only IBM and ITT and A T and T and Dupont, Dow, Union Carbide and Exxon.  Those are the nations of the world today."

Maybe this was already true in 1976 when that film was made.  It seems to me that it is increasingly true as history marches forward and soon we may realize that the ineffectual, paralyzed government that now fails us at almost every turn is simply the logical consequence of the fact that our country, that all countries are becoming irrelevant to our safety, prosperity, happiness, and freedom.

People who fight for their second amendment rights are patsies, as the whole argument, on both sides, is intended to sell guns and ammunition and make corporations rich.  Which it is doing.  People who want us in the middle east to secure our energy freedom are likewise patsies, as the price of oil causes gasoline prices to go up when it rises, and also when it falls, and the whole point is to enrich the Koch brothers with petro-dollars.  Which it does.  People who fight for immigration reform, or against it, are simply doing the work that the multinational corporations want, and whatever adds to their bottom line will be the eventual outcome of that legislation.

And the two young men who slaughtered the innocents in Boston?  We may never know the true details even if some seeming "motivation" arises, because the truth is it really does not matter where they came from, or what ills plagued them, and it would not matter what the country we call the United States of American did or did not do.  The chain of cause and effect that led them to the state of anger, or despair, or madness, or whatever their motivation was did not proceed from the plans of any government, be it eastern or western, because governments control those causes less and less every day.

If we ever hope to find an answer to international and domestic terrorism, I suspect it we be after we re-think how the people of this planet are arranged and organized, about what constitutes, as Roger Waters wrote, "Us and Them."  We may have to realize that we are citizens of an organizing system that we neither understand nor control, that we don't even really see.

Primer

I love this movie: http://www.imdb.com/title/tt0390384/

I've watched it so many times I've lost track... which, oddly, fits neatly into the theme of the film itself.  My friend Max Guernsey recently watched it and asked some questions that got me thinking about the film all over again.  So, I thought to write a blog about it.

If you have not seen the film, please do not read this.  In fact, please do not read this unless you've seen it at least twice.  I would hate to rob you of a truly wonderful experience by spoiling it.


Shane Carruth says he did not really start out to make a film about time travel.  He wanted to make a film about trust, the sacrifices we make (or refuse to make) for friendship, and the human desire to "get things right" in our lives.  The device Abe and Aaron create is a vehicle (pun intended) through which the film explores these themes.

The plot is confounding, no doubt.  Here is my take at untangling it:

Alert! Spoilers below...

Abe is the first one to realize what they have.  He plans to prove this to himself and to Aaron by starting the box, sequestering himself in a hotel for a while, then entering the box to go back to just after he started it.  Once he does this he finds Aaron, and together they watch the original act of Abe starting the box and leaving for the hotel.  Aaron believes what he sees, but what he does not know is that Abe secretly created another box and turned it on earlier.  It is still running, and will continue to run until/unless he decides to use it  This is his "failsafe", which he can use if things go wrong; he can go back before he decided to tell Aaron about the discovery, and stop himself from doing so if need be.  He is not sure he'll need it, but there are so many unknowns that Abe, the good engineer, takes this precaution.

We do not see Aaron finding Abe's box, but he does as we find out later (in a sense).  He moves it to another location and replaces it with a box that he activates after Abe's original experiment.  Thus, he will be able to go back before this all began, but Abe will not be able to.  Aaron does not want Abe to be able to thwart him in what he intends to do.  Note that Abe's motivations are very different from Aaron's.

Abe is dating Rachel Granger.  Their efforts are funded by Rachel's father, Thomas Granger.  At some point, in a future we do not see, Granger finds a box running (we do not know which one, or how) and uses it to come back for reasons of his own.  He may, in fact, believe he will go back to the original failsafe point and take control of the technology from the boys.  He makes the mistake of exiting the box early, however (as Aaron did when they first traveled, only even moreso) and this damages him severely.

Abe is very disturbed by this, and also by a tragic event at a party involving Rachel's ex-boyfriend, and finally decides to use the failsafe to go back and prevent the entire series of events. He does not know that his failsafe is not the original, but the one Aaron replaced it with.  So, when he goes back he actually does not go all the way.  The Aaron that Abe now encounters is already a time-traveler.  The original Aaron?  Drugged and in the attic.

Aaron tells Abe the truth... he has been looping back over the events again and again, taking a machine with him (folded up) in the failsafe and, exiting, starting the new machine up so he can go back again.  He is trying to make the "perfect day" where the tragedy at the party, and the tragedy with Granger, never take place.  Now Aaron takes two folded-up machines back with him...

We do not know (cannot know) how many loops they go through (and how many drugged Abe/Aaron versions are in the attic) before he succeeds.  But he does.  They decide to do one more loop in which they do not set a failsafe again, and start a new time line that cannot loop.  Aaron decides to go off continent so he can never encounter another version of himself, and begins to build the room-sized machine.  What he intends is unclear.  Abe stays in the states and will prevent them from ever discovering time travel in the first place.  Their friendship is over.

We also are travelers, of course, as the film was made long ago but we can restart it and watch it whenever we wish.  We do do, of course, because we want to change our experience of the film by coming to understand it better until, I suppose, we create the "perfect run" of the film.

I'm sure I am missing things here.  I like that.  The whole thing just makes me smile.

The Second Amendment

Recent mass-shootings have once again stirred up public debate about the constitutional rights of American citizens to own weapons, whether there should be any limitations or regulations regarding this, if some weapons should be banned or if people who want to buy and own them should pass a background check, etc...

I grew up around guns.  I owned a .22 caliber rifle as a kid, and later a Schmitt-Reuben 7.62 Olympic match rifle and a 20 gauge shotgun.  I got my rifle and shotgun merit badge as a boy scout. I've been hunting with my father, and was a member of the NRA and an avid target shooter in my youth.  I understand the cultural aspects of gun ownership.

But what always seems to be missing in the argument, especially from the political right, is the actual second amendment itself.  They cite "The right of the people to keep and bear arms shall not be infringed."  That's only part of it.

Here is the whole thing:

A well regulated militia being necessary to the security of a free state, the right of the people to keep and bear arms shall not be infringed.

You'll note it is not terribly long.  Most of the constitution, especially the Bill of Rights, is not very wordy.  The founding fathers tended to craft these things without a lot of persiflage or extraneous language.  The NRA interprets the amendment as essentially saying "the rights of individual citizens to own weaponry shall not be limited" but that's not what the amendment says.  If that's what the founding fathers had wanted to say, I submit they would have said exactly that.

Let's look at the whole thing, piece by piece:

A well regulated militia

What is meant here?  Consider the context of the writing: this amendment was passed in 1791, not all that long after the revolutionary war.  A big part of that war, especially in the early days, was conducted by citizen soldiers (the minutemen, and others) who were very well organized and pretty darn effective.  I submit they were what the founders were thinking about; the value of our citizens being an organized militia when needed.  And why is this necessary?  They tell us why.

being necessary to the security of a free state

The purpose is the security of the state.  That is plainly stated.  It is not, as many have suggested, so that we can fight off the ATF or the FBI when they storm our mountain bunkers.  It is so we can defend the state from a foreign invasion.  At the time the amendment was written, this was no trivial concern.  We had been invaded, and would be again (the war of 1812).

the right of the people

Note "the people" is used here, not "individual persons."   In other places in the constitution, for example in the language that mandates the census (article 1, section 2, clause 3) they refer to "the whole Number of free Persons" when referring to individuals, not "the people".  What was meant by "the people" at that time?

Consider the declaration of independence... it begins "We the People."  This refers to the nation as a whole, not individuals.  Thomas Jefferson was not declaring his personal independence from England... we were, as a collective, declaring that independence.  Also, note that Abraham Lincoln referred to our government as being "of the people, by the people, and for the people."  "The people" means the country, all of us, including the government.

So, I submit that they are talking here about a people's militia, and how needed it is to keep the country safe from invasion.  The closest analog I can think of in the modern world is the National Guard.

to keep and bear arms shall not be infringed.

Note "arms."  At the time, "weapons" were considered to be arms and armaments.  Armaments would include cannon, mortar, and other large-scale military weapons that are used to attack large groups of people at once.  The founders did not include armaments in this right, only arms, which to them would mean side arms and along arms: pistols and muskets, and things like swords and muskatoons.

A key question to ask is this:  what would they consider an assault rifle, capable of rapid fire, and sporting a magazine that holds, say, 50 rounds, to be?  An arm?  Or an armament?  Or, had they known of such things, would they have created another category or term?  What would they think of VX gas and nuclear bombs?  We cannot know the answer to this, of course, but even the most staunch NRA booster would not, I hope, say that individual citizens should be allowed to posses nuclear weapons and nerve gas.  So everyone draws a line somewhere, it's only a question of where the line is drawn.

Given all of this, I submit that the constitution does not provide an unlimited right for each citizen to own any sort of weaponry they like, without any regulation whatsoever.

If you believe we should have such a right, then make your argument based on why you think this is the right thing for our country.  But don't distort the second amendment to suit you.  In my book, doing so simply means you don't feel you can make a strong enough argument based on the merits of your beliefs themselves.

I'll close with this:  Thomas Jefferson and John Adams made it clear that they did not consider the constitution to be holy writ.  Their expectation was that we would revisit it every ten years or so, because they were smart enough to know that the world would change, and that the constitution would have to be updated and modified regularly.  Practically the first thing they did to the constitution was to amend it. Would they have put in a literal right to privacy if there had been mass communication at the time?  What would they think of the internet?  Warrant-less wire taps?  Terrorists flying planes into buildings?  Torture?

Our country is ours.  We have to ask ourselves. regularly, what kind of country we want it to be, and take responsibility for what it is and what it does in the world.

Certain Evil

I do not believe there is evil in nature.  The natural world simply operates as it does, without morals or reason, plainly in response to stimuli in the short term (action) and the long term (evolution).  Nature is a system.  Evil, like good, is a purely human issue; we interpret some things that happen one way, some another.

I am not dismissing good and evil as unimportant, I'm simply saying they exist solely in the domain of human experience, not nature.  I am neither suggesting we should, in a Nietzschean sense, seek to ignore this distinction by synthesizing a higher truth*; I believe some things are, in fact, evil.

But where does evil come from?

The men who shot 14-year-old Malala Yousafzai in the head four times simply because she believes girls should be able to go to school committed an evil act.  How were they able to do such a thing?  Because they are evil people?  I think that's likely too simple an answer.

Timothy McVeigh, when he blew up a building full of people in Oklahoma City, committed an act of evil.  The 9/11 hijackers did evil.  The Nazi's attempt at genocide was evil.  There is undoubtedly evil in the world, and all of it is created by people. 

If we set aside the actions of the completely psychotic, what remains is a clear through-line that connects in commonality much of human evil, and that is certainty.

The men who shot Malala did so because they believed this to be  the will of Allah, whom they believe to be the one true god; that girls must not be educated as boys, and that her contrary beliefs and actions meant it was right to kill her.  They did not see it as an act of evil.  They rather saw her as enacting an evil in the eyes of god.  

But they did not just "suspect" this, for any uncertainly in them would have prevented them from this horrific action.  If they had said "I think god wants me to shoot her, but I could be wrong about that" then I submit they would never have actually fired their weapons.  They might have argued against her, tried to stop her, reviled her to others, but to actually attempt to end her very life, at 14 years old, they had to be absolutely certain that they were righteous in their action.

Timothy McVeigh, similarly, believed that the United States federal government was an evil force that was destroying the fabric of this nation and our freedoms, and that this constituted a war against its citizens.  He saw himself as a freedom fighter, and that attacking a federal building was a justifiable act of war against his oppressors.  He didn't consider this as one possible interpretation of the situation, with other possibilities also arguably true, he was absolutely certain he was right, or he would never have taken the lives of so many strangers who had, directly, done nothing to him whatsoever.

The 9/11 bombers were certain they were right.  So were the stormtroopers.  

There is danger in nature.  A tidal wave can drown you, a grizzly bear can eat you, a slip off of a cliff will subject you to gravity and a deadly fall.  But none of this is evil, it just is.  Evil is in the hearts and intentions of people who are certain, absolutely certain, that they know the truth and that this knowledge justifies acts that would otherwise be evil, but are not evil because of some larger, more important truth.  In the main, I doubt that there are evil people, people who simply want to do bad things while cackling to themselves and twirling their mustaches.  I think most evil is done by people who see themselves as certainly doing the right thing, and they are so sure of this it enables them to commit the most horrible acts imaginable.

I'm not saying that certainly is the only source of evil.  Greed can cause it, anger can, selfishness can, etc...  but an awful lot of evil is committed by those who intend good, but are simply deluded by their certainty.

The cure, of course, is credulity.  We must question everything; our government, our teachers, our priests and rabbis... but mostly ourselves and what we believe.  We must never allow ourselves to disregard the possibility that the things we hold the most true may be completely wrong, and that the things we see as lies and foolishness may be correct.

Of course, that means I must doubt the very notion I am putting forth in this blog, and I do.  But to doubt does not mean to dismiss, or even disbelieve.  It means that I would never take an extreme action based on this belief.  I would never say that it is okay to kill people who operate with certainty because I believe certainty is a major source of evil in the world. 

This belief motivates me to avoid certainty in myself.  I do not believe there is a god, but I may be wrong.  I believe the second amendment is not about individual gun ownership, but perhaps I am in error.  I believe abortion should be legal but rare, but I'm willing to entertain other opinions.  I do not lack conviction in my beliefs.

I lack certainty.

---

*Or, at least, that was my interpretation of "Beyond Good and Evil" in my undergrad days.


 

The Sculptor

You never know where an insight will come from.  I've been designing software for over 35 years, but it wasn't until the last 10 that I came across Christopher Alexander's "The Timeless Way of Building" (an architecture book) because of a recommendation by Alan Shalloway, when I joined Net Objectives.

I learned a lot from Alexander, but one thing I could never quite understand was the one thing he said was actually the main thrust of the book, namely that you should favor "design by differentiation" over "design by synthesis".  The latter I kind of understood: building things by finding pieces and then putting together whatever you can with the pieces you found.  I'd done that for years -- ask the customer for details about the problem domain, make those things into objects, and then create an object-oriented design based on the objects.  This seemed reasonable, and after all what else could one do?

But Alexander said to disfavor this approach in deference to "design by differentiation".  His description of what "differentiation" actually is however, totally eluded me.  So I understood that the approach I took was not such a good one, but the better way was incomprehensible to me.  Frankly, this was kind of frustrating.

But then I got... lucky.  I tend to.  I happened upon a very kind and helpful man who, unknown to himself, resolved this conundrum for me entirely.  He was, in fact, a sculptor.

I was perusing the Bellevue Art Walk with my wife, Andrea. She is a very skilled artist, and we go to these fairs pretty regularly because she has an abiding interest in art.  The Art Walk consists of blockading several blocks around Bellevue Square (disallowing traffic) and inviting artists to display their works to the pedestrians.

I like art, but the art fair is not my favorite venue to enjoy it in; they are usually conducted on very hot days, and I seldom see any artist selling any art, so I find them kind of depressing.  I often wonder how these people are able to feed themselves.  Anyway, we'd been there for about an hour, and I was grumpy.  I was sweating in the summer heat, and totally bummed about the failure of the artists I saw to sell anything at all.  I told Andrea this, and she suggested we stop for an iced coffee, to cool off and cheer up.  It seemed like a good idea to me.

The thing is, and here's the lucky part, they had designated the parking lot of the local coffee place as the "scupture garden", and thus all the sculptors were there in a large group.  In order for me to enter the coffee shop, and thus to get my coffee, I would have to pass by them all.  Otherwise, I would not have paid them much attention, given how out of sorts I was.  I had no choice, however.

It turned out that two of the sculptors, one at the entrance of the garden and one at the far end (at the front door of the coffee shop) had by happenstance chosen the same subject matter; a particular kind of fishing bird called an osprey.  

An osprey hunts in a most unusual way; as it flies above the water it looks for the shadows of fish that are just under the surface.  Seeing one, the bird simply folds up its wings, extends its talons, and starts to fall from the sky, like a stone.  It is a large bird, and can quickly pick up speed in this way.  By the time it strikes the water, feet-first, it is moving so fast that the fish has no chance to react before it is in the clutches of the bird's very sharp talons.

But, now the bird is in danger of plunging into the water itself and, being not-a-duck, does not want to.  It would surely drown.  So, at the last minute, the bird unfolds its massive wings and, beating back against the air, reverses direction abruptly and emerges from the splash up into the sky, flying away with its prey as the splash collapses just beneath the bird.  An amazing thing to behold, this, and it was the very moment that both sculptors had chosen to capture.

Showing movement in sculpture is tricky, and they both had taken on the challenge in different ways.  The first sculptor along my path was the sort of artist who, I am imagining, goes into a junkyard or rubbish pile, and finds pieces of interestingly twisted metal, odd shapes of industrial machienery, and so forth.  Taking these items back to his shop, he assembles them into an abstract representation of his subject matter.  His product was interesting, but frankly I (as a rather naive art critic) could not really see the bird in what he had done.  I'm sure that's what the artist intended; not a literal representation of the bird, but an expression of... his own reaction to it, or something like that.

But the other sculptor, at the opposite end of the garden, was the sort of artist who works with what I considered to be more traditional methods, they way sculptors in the movies seem to always work.  Take a block of marble and, using chisels and drills and so forth, create a literal representation of your subject matter.  His osprey looked more like a real osprey to me.

In fact, this piece was unlike the typical artwork.  In my experience, most art requires that you stand back a little in order to appreciate it.  Get too close, and it begins to lose its beauty.  This piece, however, looked better and better as I got closer to it; and thus I ended up standing directly in front of it with my mouth hanging open.  It was amazingly impressive and realistic-looking.

The sculptor noticed my interest and, obviously hoping for a sale, sidled up next to me and said "you like that, do you?"

"Yes!" I replied.  Then I noted the price tag.  "And if I had $16,000 to spare, I'd love to buy it.  But I don't."

He smiled.  "No problem, glad you enjoyed it anyway.  Someone will buy it eventually."

But then it struck me.  The first sculptor, what he had done; wasn't that design by synthesis?  He started by looking for parts, and then made what he could make given the nature of the parts he happened to find.  Isn't that like looking for objects and then trying to assemble them into a structure?  In fact, I recalled Alexander saying that a design by synthesis lacked "the character of nature."  I noted that his osprey didn't look nearly as real as the one the second sculptor created.  So, maybe what the second sculptor was doing was an example of design by differentiation. 

Of course, I had no idea how such a sculpture is created. So I said "I don't want to take up your time since I'm not a potential customer here, but do you mind if I ask you some questions about how you did this?"

He was very nice and said I should ask him about anything that interested me.  The problem was, I was not sure what I wanted to ask, exactly.  So I started with an obvious one: "How do you begin?  Do you work from photos of ospreys, or drawings, or actual birds?  Do you go to the zoo?  Do you bring a bird back to your studio to observe it?"

He said "In the beginning, the bird is not important."

This surprised me.  "Really?  Well... then what is important?"

He smiled.  "The money," he said.  "I rarely work without a contract.  I don't just sculpt things in the hope that maybe, someday, someone will buy it.  I did in this case, but that's rare.  Usually I work on commission."

Makes sense, I thought.  I don't work for free either.

"So, let's say," he continued, "that you have a new building scheduled to open in the fall, and you want a sculpture of, say, a hunting osprey for the lobby.  You contact me with the request and we work out how much I'll be paid, how much I get up front, what budget I have for purchasing the marble, when it needs to be completed, and so forth."

"I get you.  But then, what representation of the bird do you use?"

"None," he said.  "It's too early for that."  As the conversation continued, it became clear to me that there was a lot he had to do and discover before even contemplating the actual bird itself.

First, he would need to visit the actual site, the lobby in this case, where the sculpture would eventually be installed.  He'd need to know the dimensions of the area (to ensure the finished work would physically fit into it, and also be attractive and "right sized"), he'd need to know the color scheme of the surroundings (marble comes in lots of colors, and a pink artwork in a blue enviroment would look clownish), the patterns of light entering the room at various times of the day, where visitors in the lobby were going to sit, and so forth.  The environment where the completed work would be installed must be taken into account before beginning the work.

Also, once armed with these notes, he would have to visit a marble quarry and seek out a piece that was of the right size, the right hue, and which he could afford given the constraints of his contract.  There may be only one piece that would fit all the constraints and requirements and limits.

Having purchased the marble, he would take it back to his workshop and examine the raw material.  Each piece of marble is different; they all have different grain patterns, flaws and cracks, weak and strong points, and if the sculptor is not highly aware of these then his work might fracture or even crumble into pieces before it is complete or when he tries to move it to the installation location.  Only certainly things are possible with a given piece of marble.

What I realized from this was that the sculpture started not with the subject, but the context in which the subject would be placed once it was completed.  Again, recalling Alexander, I remembered his phrase "design by context."

"When does the bird come into it?" I asked.

"Right about now," he said.  He had taken photographs of ospreys hunting in the twilight hours, which is their preference, and then blew the pictures up large and mounted them on the walls of his studio.  He particularly focused on images of that critical moment when the bird is emerging from the collapsing splash, taken from various angles.

"Okay, so now the actual work begins, " I said.  "How does that go?"

He explained that what he liked to do what sculpt the entire piece, from the tip of the beak to the end of the tail-feathers, from the arch of the wings to the talons with the fish captured, very quickly and very roughly.  In a scant few days, perhaps a week, he would have a completed piece; but everything would be very vague.  The bird's head would be a simple oval, the talons like orange traffic cones, the wings just large triangles, etc...  complete, but very little detail or nuance.

Having completed the work, he would stop, look at it, look at the photographs, think, and then take it on again; the whole piece from one end to the other, but on this pass over the work he would be adding just a bit more detail to each part he encountered.  Having completed the second pass, over another few days, he would stop, look at it, look at the photographs, think, and start again.  More details would be added on the third pass, and on and on and on.

As he was explaining this to me I began to think about my industry, software development, and how in the past several years we've been changing the way we work.  Where we used to think of software as an activity conducted in discreet phases (analysis, design, coding, testing, deployment) we've been moving toward more incremental approaches, as suggested by eXtreme Programming, Scrum, Lean-Agile, and the like.  In each increment we do everything from analysis to testing, over and over again.  

So I said "I'm a software designer, and I have to tell you that we're doing something similar when we make our products these days.  I think I know why we do that, but tell me, why do you do that?  Why do you work in an incremental fashion like that?"

"I started doing this because of the schedule commitment that my customers almost always want.  When I promise to deliver a sculpture in 6 months, I do so in good faith.  It is my best guess that the thing will really take 6 months to complete, but in fact I'm probably wrong.  I find it devilishly difficult to estimate how long a given piece will take because in reality while they share some similarities with other works I've created, no two sculptures are really enough alike that I can tell you how long the next on will take.  It's my best guess, that's all."

I didn't say anything, but I thought "man, I know just what you mean.  I have the exact same problem."

By working in this way, he explained, it meant that when the day came to deliver the finished piece he would have something complete and ready to display.  "It might not be the best thing I could ever do," he said, "but it will be the best I can do in the time alloted, and it will be very good.  If, on the other hand I just focused on one part of the bird, say the head and shoulders, and refused to move on until it was perfect... it's possible that the deadline would arrive and all I'd have is a head, shoulders, and a huge chunk of raw marble.  That's not going to be acceptable to my customer."

All of this washed over me, and got me thinking about the concept of "design by differentiation" that Alexander had talked about.  I thought the key to understanding this was almost in my grasp, if I just sat down and thought about it.  I thanked the sculptor for this time and started to head to the coffee shop for the iced coffee I'd originally wanted, and some time to think.

"Wait," he said, stopping me and smiling.  "I have not told you the most important part." 

"Oh?  What's the most important part?" I asked.

"This sculpture, the one you were so impressed with?  No deadline.  I just had this idea and wanted to get it into stone before the inspiration passed.  I hope someone will buy it some day, but in this case there was no commission, and therefore no schedule.  Nevertheless, I did sculpt it in that same incremental fashion."

"Why?" I asked.  "You had no limit, you could have done it any way you wanted to."

"Because," he explained, "it's the only way to do it.  I started working this way due to practical concerns, but now that I've learned how to approach sculpting incrementally I know it's the right way to proceed anyway."

"What do you mean?"

He smiled again.  "Come here," he said, motioning me with his hand, "and look closely at the osprey.  I'm going to tell you something about it and you're going to agree with me, but you won't know why you're agreeing.  You'll just know I am right."

He really had my curiosity going now.  He pointed to the bird's eye and said "see how the pupil of the eye is angled relative to the beak?  Yes?  Okay, remember that, and move around to the other side and look at the bird's back."  He pointed out, on the broad powerful back of the bird, that one could sense, under the feathers, just how the muscles were flexed.  He asked if I could sense that and I said that I certainly could.

"Here's my statement: given the position of the pupil in the bird's eye, that is how the muscles would have to be flexed.  Or, conversely, given the way the muscles in the back are flexed, the pupil would have to be positioned the way it is.  Otherwise, it simply would not be right."

I looked, I thought, and he was right.  I could not explain why, but these things matched... somehow.  He went on for about 15 minutes pointing out similar things.  Because the bird's tail was angled downward, the tips of the wings had to have a slight upward bend.  Because the talons were extended unevenly, the beak had to be slightly open and there needed to be a small bump on the back of the neck.  Because of this, that.  Because of these things, those things... on and on.  And I realized that I, since my early childhood, had seen birds in various situations and my mind had absorbed all these myriad details about what they are like, how they move, their essential nature... things I cannot really explain or describe, but when I see them I know them, and I respond because my mind says "that's right, that's how birds really are."  

This was why I'd been so impressed with the piece in the first place.  It looked real in ways that spoke to my subconscious appreciation of nature, and this created a profound effect in me.

I explained my theory to him, and he nodded.  "That's right.  Everything is the way it should be, and you felt it.  It worked because a million little details are correct."

"That's amazing!" I said, "you're clearly a genius.  How in the world could you possibly get all those details correct?"

His eyes twinkled at the compliment, but then he said, with a laugh "you've got me.  I have no idea.  It's too complicated, too subtle, too nuanced for a mere human like me to ever hope to get it right.  It's not me, it's the process itself that makes it work."

He went on to explain his best theory of why this worked.  On each iteration he was not only adding details, but he was learning about each aspect of the bird in the context of each decision he was making, as he was making it.  He, like me, had spent his life absorbing all these unspoken details about real birds in nature and, guided by this as the photographs reminded him, and guided by each decision he had just made the increment before, his current decisions were contextualized, and produced the quality of nature that a good representation must have.

"I learned," he said, "quite by accident that sculpting is not a process of planning and then executing the plan.  Sculpting is a process of learning, of unfolding.  The piece emerges as a result of a million little decisions, each made proximate to other decisions and, as each decision is informed by the previous ones, it in turn informs the next ones.  Gradually a bird is born, complete and organic and natural."

This is the process Alexander was describing, and in fact he alluded to something that might have made it clear to me in the first place:

"The image of the differentiating process is the growth of an embryo" he wrote.

We know, from the work of biologists, just how this works.  Termed "ontology" it starts with single, simple cell, which then splits into two.  These two become four, then eight, then sixteen and so on, all the cells identical to each other.  It is not until enough of the embryo exists, what biologists call the blastocyst, and we have what they term "the context of the organism" that we begin to see the cells differentiate and become the hearts and lungs and tendons and nerves, and the creature emerges in full.  

This is how nature does it, always.  Nature knows what she is doing.

So now I understand that software design should be done this same way.  Not by starting with objects and attempting, lego-style, to assemble them into a design, but rather by starting with the problem... what is important to the customer, how they make their money, what their risks and competitive pressures are, what the knowns and unknowns are, and then to start small and simple, and allow my design to emerge.

This is why design patterns work.  This is why test-driven development works.  This is why agile approaches are essential.

-Scott Bain-

2012