The book of the Russian philosopher and teacher N. E. Skvortsov (1836-1902) is devoted to the analysis of the dialogue "Teetet" - one of the classical works of the great ancient Greek philosopher Plato. The book consists of two parts. The first part contains preliminary explanations for reading the dialogue, a summary of its content and an author's study of notes to the text of the dialogue with an analysis of individual discrepancies and comments by translators and publishers of Plato's works. The second part of the work is a critical consideration by the author of the Platonic concept of knowledge.