The paper deals with the fundamental problems of Juraj Cíger’s philosophical and ethical thinking. It’s focus is on Cíger’s understanding and explaining of the legacy of the founder of modern philosophy R. Descartes as an enigmatic philosopher. In this context it shows that Descartes was the clue philosopher for Cíger and that in a sense Cíger himself can be seen as an enigmatic philosopher. The author offers an analysis of Cíger’s interpretation of Descartes’ philosophical conception, which on his opinion was not dualistic, but rather trialistic. The impact of Cíger’s thinking on the theoretical and practical (medical) ethics is shown as well.