So we are deeply wired to make sense of the world

A better plan might be to quit building more lanes and make rush hour driving as unpleasant as possible so people either change their schedules or car pool or take public transportation

And of course, that makes sense. Baking a cake is not a life or death project, but eating is. Whether you go to a movie or go to a concert is not a life or death decision, but driving there involves a continuous stream of life or death decisions and actions. Or deciding to step up onto a bus rather than stepping out in front of one.

Decisions we make rely very heavily on past experience and on what we’ve been told, which hinges on other people’s experiences. When a parent tells a child not to eat toadstools it is pretty likely the parent has never eaten one either. But somebody’s parent or child did at some point, with dire consequences, and the information has been passed along for a thousand generations. When we experience something directly, or learn from someone we trust, it builds our expectations and reinforces our sense-making.

Survival depends on having a pretty good idea of how things will work out

That’s why the unexpected can come as such a shock. Can a butterfly in China affect our weather here? Yes, but the chain of causation is so vast that no one can point at one butterfly and one tornado and make a rational connection. It’s hard enough to even detect the tiny bit of turbulence in the immediate vicinity of the butterfly, though we know it exists. So the butterfly story doesn’t have to be evaluated as truth or fiction and what we think of it doesn’t much matter. The unexpected can also be fun, even thrilling, and so figures prominently in fiction and film.

But back to driving. After some years behind the wheel, drivers accumulate a wealth of expectations, eye-hand-foot coordination, familiar routes, favorite short-cuts and so on. We have a fairly high expectation that oncoming drivers will stay in their lanes because they are likely to be as interested in survival as we are. One result of that familiarity which many of us have experienced is arriving home and not being much aware of how we got there.

On a personal level, my steep house lot fronts on two streets that wye a few hundred yards from my door. I generally park my pickup truck near the garden below my house and I generally park my car at the upper level near the front door. I use my car frequently and my truck infrequently. When I do use the truck I often make the habitual right turn that takes me uphill, without thinking, because my mind is on something else. That’s the reason when new stop signs are installed a traffic department also installs warning signs about the new stop sign, and many people still drive right through the intersection until conscious awareness catches up with the new reality.

Our expectations about driving can fool us into making very expensive decisions. It seems to make sense that the best way to reduce traffic congestion, for instance, is to install more lanes on a crowded road. Otherwise we will have horrible traffic jams. But in case after case the new lanes end up just as crowded as the former lanes. The phenomenon is referred to as induced traffic, and it happens because drivers change their driving habits in response to the changed conditions. They change the time they leave for work, they change their route, and so forth.

A similar logic can apply to parking facilities. When a city builds new parking e parking problem they had at the outset. But raising the cost of parking actually does more to solve the problem than building more slots.