a branch of philosophy that investigates the metaphysics underlying statements about possible or necessary statements.

Prolegomena to Any Future Metaphysics That Will Be Able to Present Itself as a Science is a book by the German philosopher Immanuel Kant, published in 1783, two years after the first edition of his Critique of Pure Reason.

(1785; ; also known as the Foundations of the Metaphysics of Morals, Grounding of the Metaphysics of Morals, and the Grounding for the Metaphysics of Morals) the first of Immanuel Kant's mature works on moral philosophy and the first of his trilogy of major works on ethics alongside the Critique of Practical Reason and The Metaphysics of Morals.

In Islamic philosophy, Sufi metaphysics is centered on the concept of or .

a view held by Martin Heidegger in Being and Time that holds the entire history of Western philosophy is based on privileging presence over absence.https://courses.nus.edu.sg/course/elljwp/derriduction2.htm, Presence and Absence

a 1797 work of political and moral philosophy by Immanuel Kant.