 This trajectory presupposes that the society makes no attempt to renew the resources on which it depends.  Diamond isolates factors that explain the blindness, one especially important one being the adherence to dysfunctional value systems (432–434).  Wright speaks of “sticking to entrenched beliefs and practices [and] robbing the future to pay the present” (2004, 79). For Diamond, the factors are changeable by individual and collective acts of will.  Unlike Wright, Diamond documents successes as well as failures: societies that recognized and altered their unsustainable practices before it was too late.  Historical examples of these include Tokugawa, Japan (2005, 294–306), and Tikopia, an island in the South Pacific (2005, 286–93). These societies were flexible and farsighted where unsuccessful ones were rigid and focused on the present. 