I got to work early today. Over breakfast, I watched the intersection below for nearly half an hour. From the 9th floor, it’s a completely different view than driving. You see the collective driver reactions, how tiny decisions ripple outwards. It’s a fascinating, chaotic system.

During rush hour, the intersection twice became a “mahjong table”—traffic in each direction jammed against another. Four streams of cars formed a kind of windmill, like a mahjong game’s starting setup. I thought it was hopeless, only solvable by a traffic cop.

The jam was massive. One direction alone was three lanes wide, buses included. The line blocking that probably stretched to the next intersection.

Surprisingly, this “mahjong table” cleared in 20 minutes. How? First, southbound traffic backed up from the next light (imagine this cascading down the line – that’s why jams move on navigation apps). The light turned green, southbound cars kept coming, blocking the intersection and halting westbound traffic. Westbound traffic then blocked northbound. Crucially, the southbound flow wasn’t constant; it crept forward. That’s where things fell apart. If a single car lagged, impatient eastbound drivers, pressured by the queue behind (even without honking), would cut in, knowing it’d worsen the jam. Eastbound traffic, blocked by northbound, in turn blocked southbound. The “mahjong table” was set – a self-destructive loop.

Five minutes later, the lanes cleared, but the central knot remained. A bus driver stuck his head out, trying to direct, but no one budged. Even scooters were stuck.

How did it untangle? After 10 minutes of gridlock, drivers got restless. Initially, it was all about gaining an inch. But, at a certain point, a few drivers led the change, everyone’s behavior flipped. They realized they had to yield to avoid a lose-lose, or maybe the cost became too high. Cars started making right turns or U-turns, taking detours. The knot shrank from three lanes to two, then one, finally dissolving.

Drivers were noticeably friendlier during the untangling. No more aggressive cutting in; they let stragglers merge. People are more cooperative when they’re in better spirits.

Driving reveals human nature. It’s mostly instinct, little logic. Everyone has limited information, judging from just a few nearby cars. It’s like first-order chaos; people don’t predict the outcome, and even if they could, it wouldn’t matter. Without external input, most drivers switched from competition to cooperation in under 20 minutes. It’s quite a sight, really interesting.