On the law of sufficient reason: Leibniz, Kant, Schopenhauer

The aim of this study is to trace the course of philosophical meditations of Leibniz, Kant and Schopenhauer on the relationship between the law of sufficient reason and freedom. The question of freedom leads to the thick of philosophical issues, as it is one of the fundamental concepts of philosophy, revealing the secrets of the question of substantiality, morality, law and autonomy of the subject. Examining liberty in its intrinsic relation to the definition and proof of the law of sufficient reason is important for understanding the general pattern of development of philosophical knowledge, not only in the Modern era, but also at the boundaries of its completion in the transition to German classical philosophy, with Kant at its origin, and non-classical philosophical thought led by Schopenhauer. A study of the law of sufficient reason in the systems of Leibniz, Kant and Schopenhauer allowed us to establish the main ways of proving the law of sufficient reason and to identify directions for addressing the question of its relationship to the problem of justification of subject liberty.