possibilism

noun4

1. •
   The theory that the geographical environment sets certain constraints, but culture is otherwise determined by social conditions.
2. •
   An approach that pragmatically focuses on achievable goals rather than impossible ideals.

   • Aim at a standard of adequacy (possibilism) rather than at a standard of perfection (utopianism). — 1970
3. •
   Any of various socialist reform movements.
4. •
   The belief that possible things exist, as well as actual things.