Horst Wessel: Contributions to the Theory of Logical Consequence,Non-Traditional Theory of Predication and Logical Theory of Terms

The present work takes the decease of Horst Wessel as an opportunity to present and honour his work (and that of his group), which has not received the attention it deserves. The focus will be on works which might not be sufficiently well-known. Wessel was, as we aim to show, familiar with the international debate concerning logical and philosophical issues and strived to solve them by considering theories of logical consequence, a non-traditional theory of predication and the theory of logical terms, all of which he developed in joint work with Alexander Sinowjew. Wessel had to significantly refine these theories in order to formulate his criticism towards alternative logics and to apply the theories to a treatment of intensional contexts. He was vehemently opposed to approaches which revised fundamental laws of classical logic. Questions concerning the history of Philosophy are addressed in Wessel’s criticism of the Kantian antinomies of pure reason, in Wessel’s contributions to the problem of universals and his analyses of fatalism, tychism and antifatalism.