Knowledge of external world: Zhovkva, Printed by the author, 1925, 63 p.

The work contains historico-philosophical review of the problem knowledge of objective world  from Ancient Greek philosophy to Modern philosophy. Kostelnyk examines the problem through the prism of sceptisism and looks for ways to overcome the arguments of representatives. In conclusion, the author, referring to historico-philosophical material, debates with representatives of various movements and introduce his own conception of knowledge.

         Contents

I. The state of problem in Ancient Greek philosophy

II. The state of problem in Medieval and Modern philosophy

III. The solution to the problem