EN
René Descartes, whose philosophy is the inspiration of this essay, decided to examine his own thought. He started with doubt and he finally achieved certainty as to his own existence. The author of the 'Meditations in First Philosophy' created a bright and beautiful philosophy of thought. 'Post-Cartesian doubt' is a critical interpretation of the 'Meditations' regarding the characteristic of doubt as such. It is also an attempt at its development. After reconstructing the Cartesian doubt, the author introduces his own view in this regard. The key point of the text is the analysis of Cartesian formula of doubt by means of two categories: plurality and unity. The rest of the article contains an analysis of the self-reference of the doubt. For this purpose the author describes two possible ways of dissolving radical doubt (neutralization and meontologization), which is never easy, but is one of the most important theoretical assignments of the philosophy of thought. At the end of the text the author proposes a possible solution of this question, which is the renouncement of expectation of the unity.