What set of foundational assumptions used for understanding existence?

Foundational assumptions for understanding existence typically include the principles of ontology, epistemology, and metaphysics. Ontologically, it assumes that something exists, and that existence can be categorized into different types of beings or entities. Epistemologically, it presupposes that knowledge is attainable through reason, perception, or experience. Metaphysically, it often involves assumptions about causality, the nature of time and space, and the relationship between mind and matter.