FTA staffer: Welcome to Washington, Socrates! The literature and philosophy students on our staff can’t stop talking about you, and suggested you could help us think something through. They told us you ask good questions.
Socrates. I hope I can help.
FTA staffer: So we invited you here because we are devising a new way to decide which transit projects are worthy of funding, anything from a little streetcar to a busway to a big subway line.
Socrates: And when you deem that a transit project is good, do you mean that it has some intrinsic goodness in character – perhaps its pleasing color or shape – or do you mean that its goodness lies in providing some benefit to others?
F. In the benefit, certainly. It’s how to describe the benefit that gets us into trouble. Our policy is to focus on mobility and accessibility benefits – basically, people getting where they’re going. But it’s hard to translate that into a measure …
S. You would have to define those terms first.
F. Of course. You see, for a while now we’ve been scoring the benefits of a transit project based on the amount of travel time it saves. Basically it’s person-hours or person-minutes, one person saving one minute of travel time.
S. You mean one person gets to his destination a minute sooner than he would without the project. That’s a person-minute?
F. Pretty much. We prefer to count hours because minutes seem – I don’t know – petty, somehow. But still, you know, people getting there sooner, it seemed like a good idea for years.
S. Tell me: if Jim has $1000, and Dave has $100, and each is given another $100, you would say that the two have benefited equally? Even though Jim's wealth has gone up just 10% while Dave's has doubled?
F. I don’t follow …
S.: Well, but you were counting minutes, right, not percentage savings?
F.: Of course.
S.: So one commuter from the rural fringe whose commute is cut from 80 to 70 minutes … that’s exactly as valuable as one inner city traveller whose trip is cut from 15 to 5 minutes?
F.: Well, yes … I’m beginning to see your meaning …
S: Whereas if you’d thought in percentages …
F. … we’d have valued the inner city trip more … do you mean? …
S. Just asking. Don’t people really perceive travel time changes as percentages? I mean, who would feel their options to be more transformed, and be more likely to change their behavior as a result: someone who’s travel time was cut from 80 to 70 minutes or someone who’s travel time was cut from 15 to 5? Wouldn’t the latter be the greater transformation, more likely to change behavior?
F. I see your point. Of course it’s usually easier for a project to cut 80 to 70 …
S. Of course, so that’s what you end up funding. What’s the consequence of that?
F. Well, we tend to score a lot of commuter rail and long-haul busways highly, but it’s harder to assign value to shorter-distance inner-city services like bus lanes, light rail, streetcars.
S. Because shorter distance services save fewer minutes, though a higher percentage.
F. And streetcars running in mixed traffic, of course … well, the dirty secret is that they usually don’t cut travel time at all, compared to an “enhanced bus” alternative. They can even make it longer.
S. What’s wrong with scoring streetcars low, then?
F. Well, people are telling us that streetcars in mixed traffic are just intrinsically wonderful, so we should judge them differently. They seem to encourage economic development, and yet they’re not as expensive to build as faster and more reliable transit systems, so cities see them as something that’s within reach. Anyway, we have an economic development factor that tries to keep track of that, but it’s really hard to score based on what a bunch of city boosters and developers tell us about how cool a place will be in 10 years. I mean, we wish them the best, but city boosters and developers are always saying that …
S. Of course. No neutral objective measure. Whereas travel time …
F. You’re right, travel time, for all its faults, was pretty easy to measure, and to calculate for a new project.
S. But you’re abandoning it. So what’s the new scheme?
F. Ridership! Who can argue with that? We care now about how many people are going to ride the thing, especially those who aren’t riding now.
S. Is that a new idea?
F. Well, it’s always mattered somewhat. In my dad’s day we used to score mostly on “cost per new rider,” so then it was the overwhelming factor. Then we were accused of not valuing the time of people who were already riding transit – you know – their travel time savings due to the project. It didn’t count.
S. So you abandoned that, but now you’re going back to it?
F. Not exactly, but …
S. How is the new measure different?
F. We have some other factors, like service to transit dependents …
S. But basically, the new measure is ridership?
F. Right.
S. And apart from your transit dependent clause, all riders are equally valuable? Regardless of how far they ride?
F. Basically.
S. So you’re now biased the other way? Toward the inner city service, which many people ride, and away from the long-distance commute, which serves few people but many passenger-miles, and which will score highest on travel time savings (in minutes, not percentage) because the travel times are so long anyway?
F. Yes, but there are lots of arguments that this is the right bias now. The whole point of sustainable urbanism is to limit sprawl and encourage more compact cities. When we were mostly building commuter rail all the way to the rural fringe, we were encouraging the opposite. In fact, I’ve met people who moved from an inner city condo to a two-acre horse farm solely because a new commuter rail line made it possible.
S. Sounds like the right bias for you, then. But tell me, isn’t the world changing pretty fast right now? I caught up on some of your media in the time machine. It sounds like costs of transportation are shifting rapidly and people in the know expect options to be much different in just a few decades. In fact, fear about the rising cost and impact of transportation is part of why you want people to live closer together, right?
F. Absolutely.
S. Now, when you build something big and expensive like a rail line, you’re not doing it for the benefits tomorrow, right? You’re doing it for benefits further into the future.
F. Forty years at least.
S. Forty years. So if you’re judging the merit of a project based on ridership, that must mean you know what its ridership will be 40 years from now. Do you have many studies from 40 years ago that correctly describe ridership today?
F. Well, so much can happen in 40 years, you really can’t predict …
S. But if you expect forty years of value, shouldn’t you at least be looking at the middle of that window, say 20 years out?
F. Well, I suppose, but that’s really the outer edge of what anyone can predict.
S. In any case, you don’t know about your project’s ridership the way you know about its travel time. You can figure the travel time of a new service pretty exactly, but the ridership … that’s a prediction, right?
F. Of course.
S. So your new policy shifts your focus from a fact to a prediction. Even as you admit that ridership prediction is often wrong on opening day, let alone 20 or 40 years out.
F. But they always get the order of magnitude right! And of course things happen that they couldn't have foreseen. And you know, ridership prediction is always getting better. Experts are always re-calibrating their models, bringing in new factors.
S. What are the calibrations based on?
F. Well, it’s complicated, and kind of mysterious even to me. But the basic idea is that they look at the predictive factors, like travel time and land use and user experience so forth, and find examples where similar factors have led to certain ridership outcomes.
S. In the past.
F. Well, of course in the past. What else do we have?
S. But you just agreed that your world is changing more and more rapidly, which means that a given year is less and less like a year a decade earlier. Doesn’t that mean, logically, that the past is becoming less relevant?
F. Well, we try to use the reasonably recent past.
S. But you need a lot of data points, surely, to calibrate? And if the world is changing faster, doesn’t that mean that the “reasonably recent past” is shrinking? I mean, faster change means that conditions ten years in the future are much more different from the present than conditions ten years ago are. So logically, you can’t look as far into the past as you used to, to calibrate your models.
F. Well of course it fluctuates. But over the long run, I see your point.
S. So aren’t you approaching a condition where you run out of past? Reach a point where the only relevant examples are so recent that they’re only just past opening day, and there simply aren't enough data points in so brief a period?
F. You’re right. Logically it makes no sense at all. But what else would we do?
(Pause.)
S. Well, what’s the purpose of public transit?
F. Oh that’s easy. Public transit delivers a range of benefits that all go toward building a stronger, healthier, and more just America. It is the lifeblood and foundation of cities, which are the engines of the innovation that will keep our country strong and competitive. Public transit serves the cause of environmental and social justice, helping low-income and minority participate in the life of the city, so that they can climb the ladder of success by their own hard work. And of course, it’s all about jobs–-
S. Wait. That’s a lot of purposes! How on earth would you measure all of those things?
F. Well, public transit has lots of benefits! That’s what makes it so essential to a strong, healthy, and just Amer–
S. But I asked about purpose, not benefits. My business, philosophy, has zillions of benefits. You wouldn’t be here without it, and you certainly wouldn’t be thinking this clearly. But philosophy’s purpose is not too hard to capture. Maybe something like “understanding the fundamental nature of existence, and what this may imply for how people should live.” We philosophers argue about the details, but we’re positively unanimous compared to all the ways you describe transit’s purpose.
F. Well, we don’t really use the word purpose much.
S. Tell me, what’s the purpose of the police?
F. Well, law enforcement of course.
S. But policing has lots of benefits! Controlling crime is important for investment, and thus for prosperity. It contributes directly to quality of life, maybe even to happiness. And besides, police do good works for all kinds of community causes. And if you didn’t have police, you wouldn’t have plots for many of the stories that your people find entertaining, from detective novels to forensic dramas! And admit it, don’t ten year old boys find sirens exciting?
F. Yes, policing does all those things. But law enforcement, you know, that’s their real job, isn’t it? They generate all those benefits simply by doing their job, which is law enforcement.
S. Exactly. So it’s not enough to talk about transit’s benefits. You have to think about its purpose, or as you put it, it’s real job.
F. Well, moving people …
S. Anywhere? Around in circles? Is a Ferris wheel public transit?
F. No, I mean to their destinations. Except for tourists and recreational riders maybe. They like to go in circles sometimes.
S. So apart from tourists, transit is about people getting to where they’re going?
F. Sure, that’s the thing transit does I guess. And it does it in shared, scheduled vehicles instead of each one driving alone.
S. Well, we could spend another hour getting down to a definition, but the first thing that comes to your mind is often, in the end, the most useful one. “Moving people,” you said, “to their destinations.”
F. That sounds like a good start.
S. The destination, of course, isn’t really just a place but an intention, right? We want to get to work, to home, to school, to a recreation opportunity.
F. Right. That’s why cool people are talking about access now, not just mobility. Mobility is how far you can move, but access is how much useful stuff you can get to quickly. So transit also has this role of helping things to get built closer together, so that things you need aren’t as far away. That’s called density, but it doesn’t work without transit, so transit helps to stimulate it. So I guess that’s a purpose too.
S. Is that separate purpose of transit? Or just another benefit? In other words, can you serve that purpose best just by making it really easy and fast for people to get where they’re going?
F. Well, the developers and city boosters don’t think so. They think we need a separate measure to capture the way transit might stimulate development, quite apart from its usefulness in getting you places.
S. But developers are merchants, right? They need people to buy their product.
F. Of course.
S. So let’s think about their customer. If you’re deciding whether to live in a transit-oriented place, you’re going to care about the transit, right? It has to be there. It has to be good, right?
F. Right. That’s why transit effectively stimulates development.
S. But what does that customer care about, really? The ability to get where they’re going, right, since that’s transit’s purpose?
F. Of course.
S. So even the development output of transit, as you’re describing it, is ultimately about travel time. How soon you get where you’re going – that’s travel time, right? That’s the thing about transit that would attract people.
F. Well yes, but there are so many other emotional factors that affect people’s choices, right? People just like certain transit technologies, so they use them more.
S. What, for example?
F. Well, streetcars, you know, in mixed traffic. Such a huge political movement. No travel time benefits at all, really, but this huge emotional response. Developers just love them, because their customers do. We figure, by counting ridership, we properly include those factors.
S. Suppose your Parks agency does some improvements to a park, builds some new attractions there, and as a result more people come. Does that mean it’s something you should have funded?
F. Well, no, I mean, we’re a transportation agency.
S. That’s right. In fact, I was reading your “Notice of Proposed Rule Making” in the time machine, and noticed it explicitly says that “mobility and accessibility are the primary benefits of transportation investments.
F. That’s right.
S. So if a project is not delivering those benefits, that doesn’t mean it doesn't provide any benefits, right? It just means it doesn't provide the benefits that your agency is responsible for delivering, so it's not your job to fund it. It could still be funded by others, even other government agencies, the way a new statue in a park might be.
F. Yes, this is the argument that we should value mixed-traffic streetcars exactly the way we value brick paving and planter boxes, as amenities whose purpose is to attract investment. It makes sense, but somehow, because streetcars move, and people can ride them, people insist that we fund them as transit services, even though there's no mobility or access benefit compared to an "enhanced bus" option.
S. Hmm. But again, we’re talking about long-term investments, right?
F. Certainly.
S. So with your ridership metric, you must show that lots of people will be attracted to a streetcar when you open it, even in the absence of travel time savings, and you do that by effectively citing recent examples where streetcars replaced buses and ridership went up, even though the service wasn’t any faster than before.
F. Right. That’s a nice example of the problem with judging projects on travel time.
S. But in addition, because this is a long term investment, you must show that the emotional reaction that is causing this extra ridership is durable over the long term, don’t you? That people will continue to have that preference for streetcars even when streetcars are no longer a novelty, and even as other technologies improve their ability to do the same things?
F. Well, of course, nobody can know that.
S. No, that would certainly be a prediction. But are some predictions maybe more confident than others, purely on philosophical grounds?
F. Well, that’s your department, Socrates.
S. It’s not hard. Your new evaluation system is based on ridership, and we’ve talked now about two causes of ridership. One is various emotional attractions of a vehicle, like the streetcars you mentioned, but the other is travel time — ridership that is attracted because transit gets people where they’re going quickly. Your models already weigh that, don’t they? They already assume that travel time is a major indicator of ridership?
F. Absolutely, and on very solid grounds. That’s always been true.
S. Truer than you think maybe. If I hire a – well, you might call it a pedicab – to get me across Athens, perhaps because I am late to meeting some friends there, I do it because I’m in a hurry, or more exactly, I want to be at my destination now, because my life is on hold until I do. The young men who run with those carts go much faster than I can walk. I get on with my life sooner, and so they get my ridership.
F. So …
S. So I can assure you that in my home era, 2500 years ago, people already care about travel time. Certainly, a time that we consider fast would strike you as slow. But we want to get to work on our tasks, which require being in certain places. We want to get home to our families. We want to see our friends and get a good seat at the theatre. Our armies want to get to battlefields before their enemies do. So usually, when we set out on those trips, it’s with a desire to be at the destination, to already be doing whatever we were going to do there. Of course, sometimes we pause to smell the flowers, and enjoy the trip, and sometimes we walk around just for pleasure. But most of the time, we need to get there.
F. … and because people have always cared about that, for many centuries, it would seem to have more predictive value! If we have to predict, we should give more weight to factors that have governed ridership more consistently over longer spans of history … Is that what you’re saying?
S. So suppose the project you approve runs for 100 years, as much of your old transit infrastructure has already done …
F. 100 years … Well, I can’t begin to imagine what my great great great grandchildren are going to value when it comes to technology, or even what their choices will be. But you’re right … I’m on firmer ground guessing that they’ll want to get where they’re going, and soon.
S. … which means …
F. Travel time! Damn you, Socrates!
S. So why are you abandoning travel time again?
Pause.
F. Look, I think there’s a deeper problem with travel time. It connects with people when they’re thinking about the trips they make, but it doesn’t connect to – well, city builders, you know? Architects, developers, urban visionaries, and a lot of ordinary citizens who are excited by their ideas. You even have academics and urban designers saying transit should be slower, to encourage people to not travel as far, as though we could ever do that kind of social engineering. How can we keep talking about travel time in the face of all that?
S. Well, then, what’s another way to describe it?
F. Hmm.
S. What do people in your country value? What motivates them?
F. Too many things. You have fresh eyes on it, Socrates, what do you think?
S. We’re in Washington DC. Look around, on the monuments. Or turn on the radio, anywhere in this country it seems.
F. Liberty, you mean. Freedom.
S. People in most countries value freedom, but nobody talks about it as obsessively as Americans do.
F. Well, of course. It was a rallying cry of our revolution, and then of the fight against slavery, and certainly World War II. Longing for freedom, and then more recently a desire to liberate others, drives so much of our history …
S. Well, then, why don’t you base your evaluation method on freedom?
F. You don't mean that freedom boils down to travel time, do you? That would be a hard line to sell.
S. But if people can get places faster …
F. They can get to more places in a given amount of time, so they have more (snaps fingers) … choices!
(Pause. S and F look at each other.)
S. During that infernal time machine ride, I saw some footage of your southwestern cities, which seem to be fleeing from themselves across the desert. And I noticed the same shop everywhere … a “convenience store” you call it. They were advertising that customers had a choice of several flavors of something. But their slogan was, “Americans love the freedom.”
F. Yes, freedom of choice.
S. So faster travel means …
F. Literally more stuff within reach. So more choices. And hence more freedom. Not just choices of flavors or gas stations or convenience stores. It means you have more choices of schools for your children, paths for your career.
S. Those sound like important freedoms, freedoms that people fight for, as we did.
F. Yes!! (Pacing.) You’d have to refine it. But surely, if you can get where you’re going sooner, that means you can get to more places in a fixed amount of time. More of the city is available to you – more jobs, friends, places to shop, unusual things that you value. You can do more of whatever you want to do, which is part of being whoever you want to be. Sheesh! Now I sound like the Education Department! But … but this is transportation’s place in the same crusade, isn’t it?
S. Even in my day, people leave small towns for the city, because there are more options there. Freedom of choice, you’d call it.
F. So … it’s not travel time, exactly. It’s more like … Yes! I remember this funny little tool that Walkscore.com created. (Sitting at desk, typing urgently). Here it is! Look here … (rotates the monitor, triumphantly)

S. A map of San Francisco. And you have a Greek word for those blobs …
F. “Isochrones,” yes! We’d never say that word in public, of course, but those blobs show how much of your city you can get to on transit in a given amount of time, depending on where you are. The idea was to help people see the transit mobility consequences of their choices about where to locate. You' move the red pointer, and the blobs would show where you can get to quickly if you locate there. But really … it’s a map of … freedom!
S. So …
F. So, what if our metric was: How much does a project grow these blobs? Reduce travel time, but specifically with the effect of bringing more choices into range for each person, so they have more freedom! Not just the freedom to ride your horse in any direction on a ranch, but the freedom to make real choices, about friends, work, values that arise from the options presented by a city!
S. Grow the blobs in any direction?
F. Of course not, that would be the old model of mobility. It would be about access. Not just square miles of area you can get to, but the amount of stuff in them. Something like “how many new choices – jobs, shopping, schools, houses of worship or philosophy, sports facilities, and so on, are brought within a given travel time of how many people, just because of this proposed project?”
S. One given travel time? What will it be, 17 minutes?
F. (Laughs.) Imagine getting consensus on that! Several travel time thresholds of course. As you pointed out, we care about cutting travel times from 20 to 10 minutes, at least as much as we care about cutting them from 80 to 70 … Or, wait, maybe we care more! Is there a way to do this with percentages, as you suggested …?
S. Lots of details to work out, but philosophically …
F. This isn’t just philosophy, Socrates! Even better, it’s rhetoric! “FTA to score transit projects on liberation value!” “President Obama puts freedom at the center of transportation policy!”
S. So why is your agency abandoning travel time as a criterion for selecting projects?
F. (Sighs. Collapses in his chair.) I don’t know, Socrates. It seemed like the thing to do. I have to admit I was never comfortable, and I’d love to chase this idea of freedom as the ultimate measure. But in the end, you know … people really, really love streetcars, even the really slow ones in mixed traffic, and this measure won’t score those very highly! I mean … Would people really sacrifice streetcars for freedom? In America?