Karl Leonhard Reinhold (26 October, 1757 - 10 April, 1823) was an Austrian philosopher. He was the father of Ernst Reinhold, also a philosopher.
Reinhold was born in Vienna. At the age of fourteen he entered the Jesuit college of St. Anna, on the dissolution of which (1773) he joined a similar college of the order of St. Barnabas. Finding himself out of sympathy with monastic life, he fled in 1783 to North Germany, and settled in Weimar, where he became Christoph Martin Wieland's collaborator on the German Mercury (Der Teutsche Merkur), and eventually his son-in-law.
In the German Mercury he published, in the years 1786-87, his Briefe über die Kantische Philosophie (Letters on the Kantian Philosophy), which were most important in making Kant known to a wider circle of readers. As a result of these Letters, Reinhold received a call to the University of Jena, where he taught from 1787 to 1794.
In 1789 he published his chief work, the Versuch einer neuen Theorie des menschlichen Vorstellungsvermögens (Essay towards a New Theory of the Faculty of Representation), in which he attempted to simplify the Kantian theory and make it more of a unity. In 1794 he accepted a call to Kiel, where he taught till his death in 1823, although his independent activity had come to an end.
In later life he was powerfully influenced by Fichte, and subsequently, on grounds of religious feeling, by F. H. Jacobi and Bardili. His historical importance belongs entirely to his earlier activity. The development of the Kantian standpoint contained in the New Theory of Human Understanding (1789), and in the Fundament des philosophischen Wissens (1791), was called by its author Elementärphilosophie.
"Reinhold lays greater emphasis than Kant upon the unity and activity of consciousness. The principle of consciousness tells us that every idea is related both to an object and a subject, and is partly to be distinguished from and partly united to both. Since form cannot produce matter and a subject cannot produce an object, we are forced to assume a thing-in-itself. This is a notion which is self-contradictory if consciousness were to be essentially a relating activity. There is therefore something which must be thought and yet cannot be thought.
According to editor Karl Ameriks, "...Fichte, Hegel, Schelling, Schiller, Hölderlin, Novalis, and Friedrich Schlegel all developed their thought in reaction to Reinhold's reading of Kant...." There is a Faustian tendency in Reinhold's assertion that a person can hope for a future reward only because that person is constantly striving to be good. It is not moral to be good merely in the hope of reward. Reinhold's emphasis on history is evident in his declaration that philosophies and religions are to be judged on the way that they respond to the needs of reason in a particular era. Philosophical development, to him, has an underlying rationality. New philosophies are fated to struggle repeatedly in order to survive in a dialectic of history in which progress is unconsciously occurring. With regard to a transcendent God, the human internal moral law is externalized in such a deity. This extreme otherness or alienation is part of a rational process. It makes possible a subsequent deeper regaining of the self through something other than the self.
Kant's important realization was that the possibility of metaphysics can be established. This can be done only by describing what occurs when the mind is conscious of objects. Kant's weakness was in being overly concerned with the objects themselves. He remained at the second, less basic, level of philosophy. He rarely examined what occurred in consciousness, which is the basic level of philosophy. Kant did not provide a phenomenological description of consciousness. Reinhold was convinced that Kant should have identified the fundamental fact of consciousness that was essential in making cognition itself possible.
Reinhold's Essay towards a New Theory of the Human Faculty of Representation is a description of the main parts and attributes of consciousness. In writing this book, Reinhold turned his attention from the moral issues that Kant addressed in the end section of his Critique of Pure Reason to the epistemological concerns of the beginning and middle sections.
Reinhold examined the necessary conditions of representation, such as subject and object, that must exist in order for an object to be consciously present.