Abstract
On the basis of the works Personality and Paths of self-discovery the concept of self-knowledge of Ukrainian and Polish philosopher Stefan Baley has been reconstructed. It has been shown, that self-knowledge both in Baley’s philosophy and in the philosophy of Socrates has the character of the specific imperative, a certain kind of the obligation of every thinking person. Socrates and Baley are the supporters of the absolute truth, which is understood as practical value, which is beneficial to the moral cultivation of the person. The differences between the concepts of self-knowledge of Socrates and Baley lies in the fact, that Baley consider the soul of a man as the object of self-knowledge, but before self-knowledge a man needs to know another person. The second specificity of Baley’s concept is associated with worldview. In the worldview he sees the path to knowledge of the truth. It has been proven, that Baley’s views on the interdependence of the subject and truth are associated with his philosophical position, formed in the Lvov-Warsaw philosophical school.