A general concept of Unification thought is the principle of dual purposes: the view that entities in the universe exhibit dual purposes, simultaneously having both purposes for the whole and for the individual. The purpose for the whole means that by which the individual contributes to the preservation and development of the larger entity, and the individual purpose refers to the need to support an individual's own multiplication, development, self-preservation, and self-strengthening. These purposes for the individual and the whole are not independent but interdependent, and thus provide an explanation for the observed harmony in the universe.
This principle of dual purposes is very evident in the case of beavers. Next to humans, no other living animal does more to shape its landscape. In order to provide a suitable habitat for their own survival, development, and multiplication, beavers build dams. These dams provide numerous values for the larger ecosystem. They create wetland habitats for other species, help in the control of flooding and erosion, help in water cleansing, and produce a more fertile land through retention of silt.
Unification thought also recognizes the benefit for the whole can take the form of "hyung sang" (for the environment, other animals, etc.) and "sung sang" (for humans). In the case of humans, beavers have provided direct economic benefit through fur and scent glands for perfume, and even food. They have added to human enjoyment of life, both directly and by increasing the diversity of species in the area of beaver dams. Unfortunately, the human role towards beavers, as stewards of creation, has not always been so kind, nearly driving the European beaver to extinction and at one point endangering the America beaver. Fortunately, the American beaver has now made a comeback. Misguided human efforts to introduce beavers to new environments have led to their being considered a pest species in Argentina.