Ever since April of 2009, when Human Transit blogger Jarrett Walker posted a review of Darrin Nordahl's book My Kind of Transit, the transit world has been divided between the pragmatic Walkerists and the hedonistic Nordahlists. Or something like that. From what I can tell, Jarrett (who I've had a fair amount of email and blog contact with over the years) and Nordahl (who I've never been in contact with) are both nice guys. They like each other, and get along well despite their differences of opinion. They've each got new books out, and treat each other with the same respect in those books. The bottom line is that they both want to see more transit in the world. If only all disputes could be so civilized.
I'm not the first blogger to try and reconcile these two. Lloyd Alter goes and name-checks Vitruvius, summarizing the differences between Walker and Nordahl's philosophies as expressing the contrast between "commodity" and "delight." Tom Vanderbilt can't beat that, but he cites Charles Leadbeater on the difference between "system" and "empathy." I'll go one further: Jarrett and Nordahl are both right, and both wrong. And I'll bring in two experts to back me up: Michael Kemp and Virginia Postrel.
First, Kemp. In 1973 he pointed out that "given the initial decision to travel, transit riding will be higher when the relative prices of substitute modes are at their highest." What are those "substitute modes"? Walking, cycling, taxis and of course, private cars. The success of transit is dependent on the failure or cars. In fact, as I pointed out in 2008, of all the benefits advertised for transit, all but one come from getting people out of their cars. Jarrett and Nordahl both ignore that (possibly out of a desire to be taken seriously), but the result is a difficulty in maintaining perspective in transit discussions.
Now, Postrel. When people choose transit (as opposed to one of the substitute modes like cars), they don't just make the choice once. A person who has any transit available, and any car available, is faced with a choice between transit and driving over and over again. But there is not even one kind of choice between transit and car (or bike or walking). There are four kinds: Single Trips, Habits, Investments and Subsidies.
It is a very different kind of decision to take the bus, or the train, or the tram, or the cable car, or a private car, for one Single Trip than it is to choose to take one mode on a regular basis. If we take the bus once and it gets stuck in traffic, then we can take something else on the next Single Trip. But if we've made a habit of taking the bus, then it's harder to change. Investments are even harder: if someone buys a house in some desolate part of Lattingtown with no transit, that constrains their options. Subsidies are also different: because Andrew Cuomo decided to build a jumbo-sized Tappan Zee Bridge, and because Kate Slevin decided not to challenge him on the size of that bridge, a lot more people will find it easier to make Habits out of driving than if a jumbo-sized bridge is not built.
There are four factors that affect our mode decisions: Availability, Value, Amenities and Glamour. This is where Postrel comes in, because Glamour is her specialty. Glamour is when someone makes a decision based on a fantasy, usually some kind of escape fantasy. One great example she gave was a book called Life Would Be Perfect If I Lived in That House. Of course life will not be perfect no matter what house you live in. But we all have these yearnings, some of us more than others.
It is essential to note that these factors affect the different kinds of decisions to differing degrees. Availability is of course the baseline, because you can't chose a mode at all if it's not Available. Glamour and Amenities count much more for Single Trips, while Value counts for Habits. Glamour also counts for Investments and Subsidies, like the magical house that just might be out in Lattingtown somewhere, or the bridge that will somehow make commuting by car to an office park in Purchase bearable.
That's why Jarrett and Nordahl are both right. Jarrett is talking about Habits, and of course the most important thing for Habits is Value. Nordahl is talking about Investments and Subsidies, and getting people to take that first Single Trip, and Glamour and Amenities are hugely important for those choices. They both agree on Availability, of course.
So if you're trying to get people to ride transit (which means getting them to choose transit over driving a car), who should you believe, Jarrett Walker or Darrin Nordahl? That entirely depends on what kind of decision you're trying to get people to make. If it's a Single Trip, go with Nordahl. If it's a Habit, go with Jarrett.
If it's an Investment or a Subsidy, it's more complicated. You need both, because Glamour will sell the apartment, but Value will keep them in it. Glamour will sell the subway line, but Value will keep people riding. Glamour without Value leads to abandonment as soon as the next glamorous project comes along. Value without Glamour will never sell, because there are tons of shallow people out there that are incapable of making an Investment or Subsidy decision on the basis of Value alone.
For transit in general, and specifically for the Investment and Subsidy decisions, we need a balance of Glamour and Value, of empathy and system, of delight and commodity, of Nordahl and Walker. And for God's sake, we need to keep in mind that transit doesn't exist in a vacuum, and at the end of the day the main reason we want more transit is to get people out of their cars.