"Cognitive dissonance" is a book by the famous psychologist Leon Festinger, which deals with the phenomenon of internal tension that arises in a person when a contradiction in his ideas or behavior comes into contact. The author examines how a person avoids this dissonance, and how it affects his life. The book examines examples from different areas of life: from choosing products in the supermarket to important life decisions. "Cognitive dissonance" gives the reader the opportunity to better understand himself, his actions and motivations, which contributes to the improvement of the quality of decision-making and inner self-knowledge.