Part of our job as informed citizens and voters is to sift through the political claims that we hear and arrive at our own sense of what’s true. I’ve been listening to such claims in the transit business, and sometimes making them, for almost 30 years now. It occurs to me that one of the most important tools for evaluating these claims is something you probably learned in high school math and forgot. (Yes, some of you remembered, but I’m really talking to the ones who forgot. To those of you who just don’t like math, don’t worry if you don’t follow this next bit; just skim ahead to the example. This IS really important.)
Here it is.
Consider a statement of the form “If A is true, then B is true,” [A –> B]
IF that statement is true, then:
- The Converse, [B –> A] is not necessarily true.
- The Inverse [NOT A –> NOT B] is not necessarily true.
- The Contrapositive [NOT B –> NOT A] IS true.
One of the problems with discussions of Transit-Oriented Development (TOD) is that the term sounds much too specialized. We hear talk of TODs as a special class of developments with special requirements and possibilities, and perhaps requiring special expertise. We often hear that a certain development is or isn’t aTOD, as though transit-orientation were not — as it obviously is — a matter of degree.