. . .bands of soldiers drifted into a valley and set up camps in what appeared to be a deserted river bottom. Their shaman, Sheng Phooey, didn’t like the feel of the place at all, but the commander prevailed and they quickly built stockades to keep out tigers they could hear in the dark of night.

Over time, these stockades evolved into villages, named Slakar, Muddel, Biapp, and Smalpot.  As Phooey had suspected, and other nearby villages confirmed, this was a valley of bad luck.  The hills concentrated rainwater from deluges, overrunning the villages and their fields.

Phooey noticed that the villages each acquired a certain character.  Slakar villagers seemed to do as little as possible to get by, often hunting or scavenging berries for food rather than growing crops. Muddel always seemed to be building things: canals, fences, boats, shrines, whatever.  Biapp people were into grand plans, they tended to think big.  Their village was surrounded by piles of rocks and half-cut roads, started but not finished as the villagers became busy elsewhere and ran out of time, food, or available labor.  Smalpot people tended to fill their homes with art.  The whole place erupted in splashes of color when a good harvest was retrieved or the stars portended favorable omens.

After three years it became clear that there was a real risk of disastrous flood, and Phooey outlined some needed public works to a combined council of elders.  The Slakar elders sneered, and pointed out that they hardly had to grow crops, much less build canals or earthworks.  They were content to leave well enough alone.  The Biapp elders, or more specifically their chieftan, suggested diverting the river so high water would flow into an alternative channel the stream used to follow ages ago.  Only the Muddel and Smalpot villages seemed to have any sense of what to do.

The Smalpot village seemed to have a good plan; they built a new longhouse on stilts about the height of two people standing on each other’s shoulders.  They were going to do something anyway, so this was simply a variation on something they liked to do as a matter of course.  The poles were ornately carved, the planks leading up to the bottom floor formed an interesting back-and-forth pattern, and there were paper lanterns hanging from each corner and within each window.

The Muddel people realized they could build a levee around the area they lived in which would keep out floodwaters, perhaps for long enough for everyone to escape to higher ground as a last resort.  It was their thought that they should stay close to the water where it was cooler during the day, and also left nothing visible to marauding bandits, which were a problem even though the menfolk of the villages were soldiers. They set about piling the dirt and stones necessary to build the wall, and soon discovered they had launched a much bigger project than they had expected.

Despite the larger than expected complexity and expense, the Muddel village had their levee in place when disaster struck.  The storm hit in the middle of the night with a nearly perpetual display of lightning through blinding sheets of rain.

Slackar’s villagers move to where they had been safe before, but this was insufficient and most of them were carried off, never to be seen again.  Biapp suffered a similar fate, since they had started their diversion but forgotten about it when it was time to harvest.  Some of the remnants, when the were discovered months later, were miles downstream.

Smalpot’s long house survived the storm, but the food reserves, kept in large clay pots in ground level huts, was ruined.  The Muddel villagers shared what they could, but some of the older and sicker villagers would not, as it turns out, survive until the next harvest.

There must have been spirits at work, since the descendants of the survivors repopulated Slackar’s and Biapp’s land, and soon acquired their respective dispositions.  Slackar would be inundated, or burned to the ground, or overrun with pestilence, and the villagers would shrug their shoulders.  Whatever.

Biapp villagers seemed to like piling up rocks.  Someday they will build something out of those rocks.

Smalpot’s villagers would survive, but having done just enough to survive, they hardly prospered.  They always seemed to be going off on some whim with decorative fancy, great ceremony, and much music and revelry.

Muddel, having survived the deluge, then built a bridge over the river, and their villagers began farming both banks.  They were eventually able to replace chunks of their stockade with stone, so when marauders came they had to attack a castle, rather than a village.  Muddel, after awhile, became the seat of government for the entire valley.

The people that begin large project that can be successfully finished are therefore those with the best odds of propagating their genes.  However, when people know how much a big project will actually cost, they won’t start.  Slackers don’t do projects, and are destroyed by catastrophe, so they don’t reproduce.  “Small potential” projects are easily estimated and easily completed, but don’t yield much benefit.  Big applications are simply outside the resources of the people committed to carrying them out, so they are abandoned.

Only the people that muddle through a project of great potential but also unrealized cost and complexity are the ones that come out ahead in the aftermath.  Therefore, nature tends to select those who underestimate project size but not unrealistically so and so can afford to finish the intended project.  In short, people are wired by natural selection to underestimate project cost and complexity.