Abstract
The paper deals with the conception of transcendental and categorial concepts in the work of Thomas Aquinas. As a starting point of the exposition the discussion of this matter in De veritate 1, 1 has been chosen, where Aquinas, drawing on Aristotle and Avicenna, determines which are the first concepts of intellect. The absolutly first concept, the terminus of conceptual analysis, is the concept of being. All other concepts, both categorial and transcendental, result from conceptual addition to being. Aquinas’s conception of conceptual addition is explained in detail and used to illustrate Aquinas’s explication of individual transcendentals and categories. Finally it is shown, how Aquinas derives transcendental and categorial concepts as general and special modes of being of being as such. Translation: Lukáš Novák.