Ontological inquiry is a philosophical methodology that involves reflecting on the fundamental nature of being. It involves asking questions such as "What is the nature of existence?" and "What is the nature of reality?" It involves looking at the essential features of phenomena and how they relate to each other, and using this to make claims and judgments about the way the world is. It is used to explore metaphysical concepts such as being, freedom, identity, and truth. Ontological inquiry is often used to contemplate the ultimate truth about reality, and to develop theories about our relationship to the world.

See also: dependent arising, mutual dependency, provisional truth, universal truth