Resumo:
In order to resolve the conflicts of reason with itself, conflicts that manifest in the contradictions (Widersprüche) of metaphysical castles, Kant undertakes a self-analysis of reason to determine what it can or cannot know independently of the senses and experience. As a result of this self-analysis, he concludes that human reason can only know a priori the form of knowledge, that is, its peculiar way of knowing objects. This leads to a new way of conceiving the real world, as human beings cannot know things as they are in themselves, but only things as they appear (als Erscheinungen), thus modified by the human way of knowing. Although this new way of conceiving the real world fully expresses Transcendental Idealism, the fundamental thesis of the Critique of Pure Reason, it seems to rest on another real world that does not appear but is presupposed as the guarantor of phenomenal reality: the world of things in themselves (Ding an sich selbst). However, as presupposing the reality of things in themselves means both engaging in Transcendental Realism (transzendentaler Realismus) and resurrecting the conflicts of reason, Kant, in the Fourth Paralogism of the first edition of the Critique (1781), argues that the reality of external objects can be testified by mere consciousness (immediate perception), since human beings do not deal with things in themselves but only with phenomena. As, from this perspective, it is not necessary to leave mere consciousness (bloßen Selbstbewußtsein) to prove the reality of external phenomena (KrV, A370; A375), critics of Transcendental Idealism (transzendentalen Idealismus) saw in this thesis a striking similarity between this idealism and Berkeleyan idealism, from which they accused Kant’s philosophy of being solipsistic. In response, Kant, in the Refutation of Idealism, a text included in the second edition of the Critique (1787), states that the empirical determination of existence (internal experience) presupposes something permanent (Beharrliche) external (which is not a representation) as its condition of possibility. From this, he concludes that “the consciousness of my own existence is, simultaneously, an immediate consciousness of the existence of other things exterior to me (anderer Dinge außer mir)” (KrV, B276). Considering this manifest oscillation between defending the external real world now as being constituted exclusively by phenomena (Fourth Paralogism of 1781), now as presupposing things in themselves (Refutation of Idealism), and thus also implying the existence of an external world constituted by things in themselves, the present thesis aims to highlight a conflicting conceptual structure at the core of Transcendental Philosophy (Transzendentalphilosophie) that prevents it from effectively determining the existence of a world of real external objects. This implies concluding that Kant’s theoretical philosophy inevitably and involuntarily leads to skepticism, as it does not allow for a secure judgment about truly external real objects.