EN
The entire cognition of the human being is based on the concept of being (ens). Being is grasped by the intellect as its first concept. Every subsequent cognition consists of a development of what have been implicitly given in the concept of being. The article aims at explaining the basic structure of thinking; how exactly the concepts are divided. According to Aquinas, being non¬ being are grasped by the intellect as its first concepts; because of them the intellect is able to grasp the meaning of division and the concept of the One (unum) as the negation of the division. The concept of the One is a condition for understanding the multitude; an understanding of the multitude is a necessary condition for comprehension of the being as a thing – as something. The clue for understanding the entire cognitive process is obviously the concept of non¬ being and as such is being treated in the article.