Actual idealism is a form of idealism, developed by Giovanni Gentile, that grew into a "grounded" idealism, contrasting the transcendental idealism of Immanuel Kant, and the absolute idealism of G. W. F. Hegel. To Gentile, who considered himself the "philosopher of fascism" while simultaneously describing himself as liberal and socialist, actualism was presented the sole remedy to philosophically preserving free agency, by making the act of thinking self-creative and, therefore, without any contingency and not in the potency of any other fact.

Libertarianism is one of the main philosophical positions related to the problems of free will and determinism which are part of the larger domain of metaphysics. In particular, libertarianism is an incompatibilist position which argues that free will is logically incompatible with a deterministic universe. Libertarianism states that since agents have free will, determinism must be false and vice versa.