Journal tags: philosophy




Jessica and I went to cinema yesterday.

Normally this wouldn’t be a big deal, but in our current circumstances, it was something of a momentous decision that involved a lot of risk assessment and weighing of the odds. We’ve been out and about a few times, but always to outdoor locations: the beach, a park, or a pub’s beer garden. For the first time, we were evaluating whether or not to enter an indoor environment, which given what we now know about the transmission of COVID-19, is certainly riskier than being outdoors.

But this was a cinema, so in theory, nobody should be talking (or singing or shouting), and everyone would be wearing masks and keeping their distance. Time was also on our side. We were considering a Monday afternoon showing—definitely not primetime. Looking at the website for the (wonderful) Duke of York’s cinema, we could see which seats were already taken. Less than an hour before the start time for the film, there were just a handful of seats occupied. A cinema that can seat a triple-digit number of people was going to be seating a single digit number of viewers.

We got tickets for the front row. Personally, I love sitting in the front row, especially in the Duke of York’s where there’s still plenty of room between the front row and the screen. But I know that it’s generally considered an undesirable spot by most people. Sure enough, the closest people to us were many rows back. Everyone was wearing masks and we kept them on for the duration of the film.

The film was Tenet). We weren’t about to enter an enclosed space for just any ol’ film. It would have to be pretty special—a new Star Wars film, or Denis Villeneuve’s Dune …or a new Christopher Nolan film. We knew it would look good on the big screen. We also knew it was likely to be spoiled for us if we didn’t see it soon enough.

At this point I am sounding the spoiler horn. If you have not seen Tenet yet, abandon ship at this point.

I really enjoyed this film. I understand the criticism that has been levelled at it—too cold, too clinical, too confusing—but I still enjoyed it immensely. I do think you need to be able to enjoy feeling confused if this is going to be a pleasurable experience. The payoff is that there’s an equally enjoyable feeling when things start slotting into place.

The closest film in Christopher Nolan’s back catalogue to Tenet is Inception in terms of twistiness and what it asks of the audience. But in some ways, Tenet is like an inverted version of Inception. In Inception, the ideas and the plot are genuinely complex, but Nolan does a great job in making them understandable—quite a feat! In Tenet, the central conceit and even the overall plot is, in hindsight, relatively straightforward. But Nolan has made it seem more twisty and convuluted than it really is. The ten minute battle at the end, for example, is filled with hard-to-follow twists and turns, but in actuality, it literally doesn’t matter.

The pitch for the mood of this film is that it’s in the spy genre, in the same way that Inception is in the heist genre. Though there’s an argument to be made that Tenet is more of a heist movie than Inception. But in terms of tone, yeah, it’s going for James Bond.

Even at the very end of the credits, when the title of the film rolled into view, it reminded me of the Bond films that would tease “The end of (this film). But James Bond will return in (next film).” Wouldn’t it have been wonderful if the very end of Tenet’s credits finished with “The end of Tenet. But the protagonist will return in …Tenet.”

The pleasure I got from Tenet was not the same kind of pleasure I get from watching a Bond film, which is a simpler, more basic kind of enjoyment. The pleasure I got from Tenet was more like the kind of enjoyment I get from reading smart sci-fi, the kind that posits a “what if?” scenario and isn’t afraid to push your mind in all kinds of uncomfortable directions to contemplate the ramifications.

Like I said, the central conceit—objects or people travelling backwards through time (from our perspective)—isn’t actually all that complex, but the fun comes from all the compounding knock-on effects that build on that one premise.

In the film, and in interviews about the film, everyone is at pains to point out that this isn’t time travel. But that’s not true. In fact, I would argue that Tenet is one of the few examples of genuine time travel. What I mean is that most so-called time-travel stories are actually more like time teleportation. People jump from one place in time to another instaneously. There are only a few examples I can think of where people genuinely travel.

The grandaddy of all time travel stories, The Time Machine by H.G. Wells, is one example. There are vivid descriptions of the world outside the machine playing out in fast-forward. But even here, there’s an implication that from outside the machine, the world cannot perceive the time machine (which would, from that perspective, look slowed down to the point of seeming completely still).

The most internally-consistent time-travel story is Primer. I suspect that the Venn diagram of people who didn’t like Tenet and people who wouldn’t like Primer is a circle. Again, it’s a film where the enjoyment comes from feeling confused, but where your attention will be rewarded and your intelligence won’t be insulted.

In Primer, the protagonists literally travel in time. If you want to go five hours into the past, you have to spend five hours in the box (the time machine).

In Tenet, the time machine is a turnstile. If you want to travel five hours into the past, you need only enter the turnstile for a moment, but then you have to spend the next five hours travelling backwards (which, from your perspective, looks like being in a world where cause and effect are reversed). After five hours, you go in and out of a turnstile again, and voila!—you’ve time travelled five hours into the past.

Crucially, if you decide to travel five hours into the past, then you have always done so. And in the five hours prior to your decision, a version of you (apparently moving backwards) would be visible to the world. There is never a version of events where you aren’t travelling backwards in time. There is no “first loop”.

That brings us to the fundamental split in categories of time travel (or time jump) stories: many worlds vs. single timeline.

In a many-worlds story, the past can be changed. Well, technically, you spawn a different universe in which events unfold differently, but from your perspective, the effect would be as though you had altered the past.

The best example of the many-worlds category in recent years is William Gibson’s The Peripheral. It genuinely reinvents the genre of time travel. First of all, no thing travels through time. In The Peripheral only information can time travel. But given telepresence technology, that’s enough. The Peripheral is time travel for the remote worker (once again, William Gibson proves to be eerily prescient). But the moment that any information travels backwards in time, the timeline splits into a new “stub”. So the many-worlds nature of its reality is front and centre. But that doesn’t stop the characters engaging in classic time travel behaviour—using knowledge of the future to exert control over the past.

Time travel stories are always played with a stacked deck of information. The future has power over the past because of the asymmetric nature of information distribution—there’s more information in the future than in the past. Whether it’s through sports results, the stock market or technological expertise, the future can exploit the past.

Information is at the heart of the power games in Tenet too, but there’s a twist. The repeated mantra here is “ignorance is ammunition.” That flies in the face of most time travel stories where knowledge—information from the future—is vital to winning the game.

It turns out that information from the future is vital to winning the game in Tenet too, but the reason why ignorance is ammunition comes down to the fact that Tenet is not a many-worlds story. It is very much a single timeline.

Having a single timeline makes for time travel stories that are like Greek tragedies. You can try travelling into the past to change the present but in doing so you will instead cause the very thing you set out to prevent.

The meat’n’bones of a single timeline time travel story—and this is at the heart of Tenet—is the question of free will.

The most succint (and disturbing) single-timeline time-travel story that I’ve read is by Ted Chiang in his recent book Exhalation. It’s called What’s Expected Of Us. It was originally published as a single page in Nature magazine. In that single page is a distillation of the metaphysical crisis that even a limited amount of time travel would unleash in a single-timeline world…

There’s a box, the Predictor. It’s very basic, like Claude Shannon’s Ultimate Machine. It has a button and a light. The button activates the light. But this machine, like an inverted object in Tenet, is moving through time differently to us. In this case, it’s very specific and localised. The machine is just a few seconds in the future relative to us. Cause and effect seem to be reversed. With a normal machine, you press the button and then the light flashes. But with the predictor, the light flashes and then you press the button. You can try to fool it but you won’t succeed. If the light flashes, you will press the button no matter how much you tell yourself that you won’t (likewise if you try to press the button before the light flashes, you won’t succeed). That’s it. In one succinct experiment with time, it is demonstrated that free will doesn’t exist.

Tenet has a similarly simple object to explain inversion. It’s a bullet. In an exposition scene we’re shown how it travels backwards in time. The protagonist holds his hand above the bullet, expecting it to jump into his hand as has just been demonstrated to him. He is told “you have to drop it.” He makes the decision to “drop” the bullet …and the bullet flies up into his hand.

This is a brilliant bit of sleight of hand (if you’ll excuse the choice of words) on Nolan’s part. It seems to imply that free will really matters. Only by deciding to “drop” the bullet does the bullet then fly upward. But here’s the thing: the protagonist had no choice but to decide to drop the bullet. We know that he had no choice because the bullet flew up into his hand. The bullet was always going to fly up into his hand. There is no timeline where the bullet doesn’t fly up into his hand, which means there is no timeline where the protagonist doesn’t decide to “drop” the bullet. The decision is real, but it is inevitable.

The lesson in this scene is the exact opposite of what it appears. It appears to show that agency and decision-making matter. The opposite is true. Free will cannot, in any meaningful sense, exist in this world.

This means that there was never really any threat. People from the future cannot change the past (or wipe it out) because it would’ve happened already. At one point, the protagonist voices this conjecture. “Doesn’t the fact that we’re here now mean that they don’t succeed?” Neil deflects the question, not because of uncertainty (we realise later) but because of certainty. It’s absolutely true that the people in the future can’t succeed because they haven’t succeeded. But the protagonist—at this point in the story—isn’t ready to truly internalise this. He needs to still believe that he is acting with free will. As that Ted Chiang story puts it:

It’s essential that you behave as if your decisions matter, even though you know that they don’t.

That’s true for the audience watching the film. If we were to understand too early that everything will work out fine, then there would be no tension in the film.

As ever with Nolan’s films, they are themselves metaphors for films. The first time you watch Tenet, ignorance is your ammuntion. You believe there is a threat. By the end of the film you have more information. Now if you re-watch the film, you will experience it differently, armed with your prior knowledge. But the film itself hasn’t changed. It’s the same linear flow of sequential scenes being projected. Everything plays out exactly the same. It’s you who have been changed. The first time you watch the film, you are like the protagonist at the start of the movie. The second time you watch it, you are like the protagonist at the end of the movie. You see the bigger picture. You understand the inevitability.

The character of Neil has had more time to come to terms with a universe without free will. What the protagonist begins to understand at the end of the film is what Neil has known for a while. He has seen this film. He knows how it ends. It ends with his death. He knows that it must end that way. At the end of the film we see him go to meet his death. Does he make the decision to do this? Yes …but he was always going to make the decision to do this. Just as the protagonist was always going to decide to “drop” the bullet, Neil was always going to decide to go to his death. It looks like a choice. But Neil understands at this point that the choice is pre-ordained. He will go to his death because he has gone to his death.

At the end, the protagonist—and the audience—understands. Everything played out exactly as it had to. The people in the future were hoping that reality allowed for many worlds, where the past could be changed. Luckily for us, reality turns out to be a single timeline. But the price we pay is that we come to understand, truly understand, that we have no free will. This is the kind of knowledge we wish we didn’t have. Ignorance was our ammunition and by the end of the film, it is spent.

Nolan has one other piece of misdirection up his sleeve. He implies that the central question at the heart of this time-travel story is the grandfather paradox. Our descendents in the future are literally trying to kill their grandparents (us). But if they succeed, then they can never come into existence.

But that’s not the paradox that plays out in Tenet. The central paradox is the bootstrap paradox, named for the Heinlein short story, By His Bootstraps. Information in this film is transmitted forwards and backwards through time, without ever being created. Take the phrase “Tenet”. In subjective time, the protagonist first hears of this phrase—and this organisation—when he is at the start of his journey. But the people who tell him this received the information via a subjectively older version of the protagonist who has travelled to the past. The protagonist starts the Tenet organistion (and phrase) in the future because the organisation (and phrase) existed in the past. So where did the phrase come from?

This paradox—the bootstrap paradox—remains after the grandfather paradox has been dealt with. The grandfather paradox was a distraction. The bootstrap paradox can’t be resolved, no matter how many times you watch the same film.

So Tenet has three instances of misdirection in its narrative:

  • Inversion isn’t time travel (it absolutely is).
  • Decisions matter (they don’t; there is no free will).
  • The grandfather paradox is the central question (it’s not; the bootstrap paradox is the central question).

I’m looking forward to seeing Tenet again. Though it can never be the same as that first time. Ignorance can never again be my ammunition.

I’m very glad that Jessica and I decided to go to the cinema to see Tenet. But who am I kidding? Did we ever really have a choice?


Cennydd points to an article by Ev Williams about the pendulum swing between open and closed technology stacks, and how that pendulum doesn’t always swing back towards openness. Cennydd writes:

We often hear the idea that “open platforms always win in the end”. I’d like that: the implicit values of the web speak to my own. But I don’t see clear evidence of this inevitable supremacy, only beliefs and proclamations.

It’s true. I catch myself saying things like “I believe the open web will win out.” Statements like that worry my inner empiricist. Faith-based outlooks scare me, and rightly so. I like being able to back up my claims with data.

Only time will tell what data emerges about the eventual fate of the web, open or closed. But we can look to previous technologies and draw comparisons. That’s exactly what Tim Wu did in his book The Master Switch and Jonathan Zittrain did in The Future Of The Internet—And How To Stop It. Both make for uncomfortable reading because they challenge my belief. Wu points to radio and television as examples of systems that began as egalitarian decentralised tools that became locked down over time in ever-constricting cycles. Cennydd adds:

I’d argue this becomes something of a one-way valve: once systems become closed, profit potential tends to grow, and profit is a heavy entropy to reverse.

Of course there is always the possibility that this time is different. It may well be that fundamental architectural decisions in the design of the internet and the workings of the web mean that this particular technology has an inherent bias towards openness. There is some data to support this (and it’s an appealing thought), but again; only time will tell. For now it’s just one more supposition.

The real question—when confronted with uncomfortable ideas that challenge what you’d like to believe is true—is what do you do about it? Do you look for evidence to support your beliefs or do you discard your beliefs entirely? That second option looks like the most logical course of action, and it’s certainly one that I would endorse if there were proven facts to be acknowledged (like gravity, evolution, or vaccination). But I worry about mistaking an argument that is still being discussed for an argument that has already been decided.

When I wrote about the dangers of apparently self-evident truisms, I said:

These statements aren’t true. But they are repeated so often, as if they were truisms, that we run the risk of believing them and thus, fulfilling their promise.

That’s my fear. Only time will tell whether the closed or open forces will win the battle for the soul of the internet. But if we believe that centralised, proprietary, capitalistic forces are inherently unstoppable, then our belief will help make them so.

I hope that openness will prevail. Hope sounds like such a wishy-washy word, like “faith” or “belief”, but it carries with it a seed of resistance. Hope, faith, and belief all carry connotations of optimism, but where faith and belief sound passive, even downright complacent, hope carries the promise of action.

Margaret Atwood was asked about the futility of having hope in the face of climate change. She responded:

If we abandon hope, we’re cooked. If we rely on nothing but hope, we’re cooked. So I would say judicious hope is necessary.

Judicious hope. I like that. It feels like a good phrase to balance empiricism with optimism; data with faith.

The alternative is to give up. And if we give up too soon, we bring into being the very endgame we feared.

Cennydd finishes:

Ultimately, I vote for whichever technology most enriches humanity. If that’s the web, great. A closed OS? Sure, so long as it’s a fair value exchange, genuinely beneficial to company and user alike.

This is where we differ. Today’s fair value exchange is tomorrow’s monopoly, just as today’s revolutionary is tomorrow’s tyrant. I will fight against that future.

To side with whatever’s best for the end user sounds like an eminently sensible metric to judge a technology. But I’ve written before about where that mindset can lead us. I can easily imagine Asimov’s three laws of robotics rewritten to reflect the ethos of user-centred design, especially that first and most important principle:

A robot may not injure a human being or, through inaction, allow a human being to come to harm.

…rephrased as:

A product or interface may not injure a user or, through inaction, allow a user to come to harm.

Whether the technology driving the system behind that interface is open or closed doesn’t come into it. What matters is the interaction.

But in his later years Asimov revealed the zeroeth law, overriding even the first:

A robot may not harm humanity, or, by inaction, allow humanity to come to harm.

It may sound grandiose to apply this thinking to the trivial interfaces we’re building with today’s technologies, but I think it’s important to keep drilling down and asking uncomfortable questions (even if they challenge our beliefs).

That’s why I think openness matters. It isn’t enough to use whatever technology works right now to deliver the best user experience. If that short-time gain comes with a long-term price tag for our society, it’s not worth it.

I would much rather an imperfect open system to a perfect proprietary one.

I have hope in an open web …judicious hope.

Orangutans, Oxen and Ogham Stones

Sean McGrath is delivering the closing keynote at XTech 2008. Sean would like to reach inside and mess with our heads today. He plans to modify our brain structures, talking about the movable Web.

Even though Sean has been doing tech stuff for a long time he freely admits that he doesn’t know what the Web is. He quotes Dylan:

I was so much older then, I’m so much younger now.

Algorithms + Data Structures = Programs is a book by Nicklaus Wirth from 1978. Anyone remember Pascal? Sean went to college here at Trinity in 1983 doing four years of computer science which is where he came across that book.

Computing is all about language …human language. People first, machines second. Information is really about words, not numbers. Words give the numbers context.

Sean used to sit in his student bedsit and think about what algorithms actually are. He was also around at the birth of SGML in 1985. More words, then. Then he got involved in the creation of XML …even more words. Then the Web came along. HTML is, yup, more words. Even JavaScript is words. His epiphany was realising that HTTP was about sending words across the wire. The Web is fundamentally words.

There’s a Bob Dylan documentary called . Sean took this as a sign from God …or at least from Dylan.

Sean explains stones — horizontal lines from top to bottom. is the Rosetta Stone of Ogham writing. The translation on this particular stone is If I were you, I would not stand here. The Irish have been using words for a long time. They’ve also been hacking for a long time. Dolmens are an example of neolithic hacking.

demonstrate the long Irish history of writing unit test cases for Cascading Style Sheets. A common thread in books from the Book Of Ballymote up to was that they were from a religious background. Joyce came along with the world’s first hypertext novel, Finnegan’s Wake. Sean goes from Yeats to Shane McGowan, quoting Summer In Siam as a sublime piece of Zen metaphysics:

When it’s Summer in Siam then all I really know is that I truly am in the Summer in Siam.

The Irish will even go to war over words. Copyright was a big bone of contention between and his student in the 6th Century. St. Columba ran a proto-Pirate Bay. If you saw him coming, you’d bury your books. There was a war between St. Finnian and St. Columba in which 3,000 people lost their lives. Finally, the High King of Ireland said As to every cow its calf, so to every book its copy, the first official statement on copyright. But because books were actually written on cows (vellum), the statement is ambiguous.

Here’s a picture. Nobody in the room knows what it is. We haven’t had our brains rewired yet.

Sean loves the simplicity of the idea that computing is words. Sadly, it’s just not true. There are plenty of images and video on the Web.

Back to that picture. It’s a cow. One person in the room sees the cow.

Sean likes the idea of the Web as electronic Ogham stones. But he sought the 2nd path to Web enlightenment. He realised that not only is the Web not just all words, the Web doesn’t exist at all.

What is the true nature of the words on the Web? Here’s something Sean created called Finite State Machines for a mobile app called Mission Control that generated documents based on the user, the device, the location and the network. There were no persistent documents. No words, just evaporation as Leonard Cohen said.

There are three models for the world.

  • Model A is the platonic model. Documents exist on the server before you observe them. You request them over HTTP.
  • Model B is Bishop Berkeley’s model. Stuff exists but we twist it (using CSS for example).
  • Model C is that nothing exists until you observe it. In quantum physics there is the idea that observing a system actually defines the system.

Model A exists within Model B which exists within Model C. Model C is the general case. If you have a system that is that dynamic, you could generate Model B and therefore Model A. Look at the way our sites have evolved over time. We used to create Model A websites. Then we switched over to Model B with Web Standards. Now we’re at Model C — we’re not going to create any actual content at all. There is no content but there is also an infinite amount of content at the same time. We generate a tailor-made document for each user but we don’t hold on to that document, we throw it away. So what content actually exists on the Web?

PHP, Django, Rails, Google App Engine …on the Web, Model C wins. It’s even starting to happen on the client side with Ajax, Silverlight and Air. It’s spooky sometimes to view source and see no actual content, just JavaScript to generate the content.

Doing everything dynamically is fine as long it scales. It’s better to solve the problems of scalability than to revert to the static model. The benefits of Model C are just so much greater than Model A.

Amazon are making great services but they are rubbish at naming things, like Mechanical Turk.

So where are all the words? HTTP still delivers words to me but they are generated on the fly. The programs that generate them are hidden.

The Web is becoming a Web of silos. As the Web becomes more dynamic, it’s harder for the little guy to compete (behind me I hear Simon grumble something about Moore’s Law). So we build silos on the client side; so-called Rich Internet Applications. We’re losing URIs.

Model C is Turing complete, user-sensitive, location-sensitive and device-sensitive. It’s scalable if it’s designed right. It’s commercially viable if it’s deployed right.

But we lose hyertext and deep linking as we know it. Perhaps we will lose search. Will the Googlebot download that JavaScript and eval it to spider it? URIs have emergent properties because they can be bookmarked, tagged and mashed up. We are also losing simplicity: simply surfing documents.

So is it worth it?

. That means I reject the premise of the question. We have no choice. We are heading towards Model C whether we want to or not. That’s bad for the librarians such as the Orangutan librarian from Discworld. Read Borges’s The Garden of Forking Paths. Sean recommends reading Borges first and Pratchett second — it just doesn’t work the other way around. Now Sean mentions Borges and John Wilkins — Jesus, this is just like my Hypertext talk at Reboot! Everyone has a good laugh about taxonomies. Model C makes it possible to build the library of Babel — every possible book that is 401 pages long. But the library of Babel is, in Standish’s view, useless. He says that a library is not useful for the books it contains but for the books that it doesn’t contain — the rubbish has been filtered out. How will we filter out the rubbish on a Model C Web?

Information content is inversely related to probability said Claude Shannon. George Dyson figured out that the library of Babel would be between a googol and googolplex of books.

Nothing that Sean has seen this week at XTech has rocked his belief that we are marching towards Model C. Our content is going into the cloud, despite what Steven Pemberton would wish for.

When Sean first started using the Web, you had static documents and you had a cgi-bin. Now we generate our documents dynamically. We are at an interesting crossroads right now between Joycean documents and Turing applications. Is there a middle way, a steady-state model? Sean doesn’t think so because he now believes that the Web doesn’t actually exist. The Web is really just HTTP. The value of URIs is that we can name things. It’s still important that we use URIs wisely.

Perhaps HTML is trying to be too clever, to anthropomorphise it. Perhaps HTML, in trying to balance documents and applications, is a jack of all trades and a master of none.

Sean now understands what Fielding was talking about. There is no such thing as a document. All there is is HTTP. Dan Connolly has a URI for his Volkswagen Beetle because it’s on the Web. Sean is now at peace, understanding the real value of HTTP + URIs.

Now Sean will rewire our brains by showing us the cow in the picture. Once we see the cow, we cannot unsee it.