The fact that most of these early civilizations clustered along river
valleys was no accident. River valleys provided the most abundant
opportunities for agriculture and, therefore, the promise of surplus.
1. To take maximum advantage of river systems, however, required
the use of irrigation systems which in turn depended on a high
degree of coordination and, possibly, some property definition.
2. Use of the river encouraged a situation in which governments and
formal rules would make sense.

Как построение ирригационной системы может зависеть от института собственности?