This past weekend, I was sitting on a tarmac, my plane queued up in a long line, waiting for a runway to open, and I was staring absently at the lights embedded in the asphalt. On some of the straightaways, I could see a long line of green lights, but there were a couple spots along the way where the lights alternated orange-green-orange-etc.
I started automatically generating hypotheses. I couldn’t see any straight line paths with orange lights, but maybe it was a question of the angle I was seeing them at. The nearest set of orange lights I could see was on a curve; maybe unless you were looking at them dead-on, they were orange, reminding the planes to stay on track. I craned my neck and looked around once my plane started trundling forward, to see if any individual light flicked over once I was at a different angle. No dice.
Ok, on to the next idea. Maybe the orange-green-orange pattern marked curves, so they were neatly differentiated from straightaways. This one held a little longer, until I spotted some short, straight stretches of alternating lights, just the width of a runway, where one trail crossed another. That led to my last hypothesis, that the orange lights marked any place where a plane could be crossing someone else’s path (after all, most of the turns were merges). But my much delayed plane finally took off before I had the chance to try to falsify that last idea.
While I was trying to puzzle out the runway lights, every time a hypothesis failed I had a quick flair of frustration. I’d actually learned more, but it felt a little like I’d screwed up, and I had an impulse to add epicycles and twist the facts to fit the theory. Ruling out hypotheses meant I had more data, and a slightly richer model of the signal, even if I didn’t yet know the rules. The flicker of annoyance faded out when I reminded myself of this fact.
But I was playing on an easy setting. I had no skin in the game, and I didn’t even have a seatmate to embarrass myself in front of since I was speculating privately. It’s nice to encounter the rationalization reflex in a low-stakes environment, where it’s easier to notice and overcome. Generating and discarding hypotheses is a way to be engaged with my surroundings and to drill the habit of being excited to discover a theory doesn’t work.
The next time I start to flinch away from noticing a hypothesis doesn’t hold up, I can remember that I know not to trust that feeling. Or, more accurately, that it’s a signal that I know more than I did a moment ago, just like the pain in my arms when I do push-ups is a sign I’m getting stronger.

(tangent) The one I haven’t figured out is, for airplanes where you board from the ground (i.e. from the terminal, you walk along the tarmac for a bit, and then onto the plane via the steps), why aren’t you allowed to walk under the wings? This is a very common setup in Europe and I can’t see a good reason for it. Answers on the back of a postcard.
White lights and paint are runways, blue lights and yellow paint are taxiways; signs are also color coded, with yellow-on-black, black-on-yellow, and black-on-red referring to different things.
Green lights are runway threshold lights at the approach end; you should rarely if ever see those from the ground; red lights are the threshold lights at the departure end of the runway. (Typically a piece of pavement is two runways, one going each direction; the threshold lights are green one direction and red the other.
Green lights are also taxiway centerline lights, while yellow taxiway lights are installed at some taxiway hold position locations.
Did you consider that the lights might be chosen to indicate function, rather than form?
Which airport was it? Research might be useful. (With a flight number and the time it started to taxi, more research might be possible.)
JFK. And I thought indicating form might be a kind of function, since the pilot might want redundancy of visual cues.
You are not allowed to walk under the wings because engines/props are very dangerous. They should be off anytime passengers are nearby, but accidents happen and the rule makes it so two accidents have to happen simultaneously.