Was ist eine Weltanschauung?

Hier bin ich auf eine interessante Präsentation über Weltanschauungen gestossen. Die Definition von J. W. Sire:

A worldview is a commitment, a fundamental orientation of the heart, that can be expressed as a story or in a set of presuppositions (assumptions which may be true, partially true or entirely false) which we hold (consciously or subconsciously, consistently or inconsistently) about the basic constitution of reality, and that provides the foundation on which we live and move and have our being.