The most significant literary work of Plutarch is undoubtedly the Parallel Lives, which consists of parallel biographies, pairing one Greek and one Roman politician or general, amounting to 48 in total, of which 46 have survived.

He also wrote the Moralia, numerous treatises on topics such as virtue, theology, religion, politics, and the role of philosophy in shaping character, primarily of public men, whose choices and actions have always determined the lives of those governed.

However, it seems that with his Moralia, he did not feel he was achieving his objective of influencing the people of his time and guiding them towards the path of virtue, in an era when the Roman Empire was at its peak and heading towards inevitable decline.

Thus, he turned to the biographies of great politicians and generals from the past, to provide more tangible and human examples - models for emulation of their great moments or to avoid their unlawful activities. At the forefront of his choices are Solon with Poplicola, Themistocles with Camillus, Aristides with Cato, Pericles with Fabius Maximus, Alcibiades with Marcus, Pelopidas with Marcellus, Alexander with Caesar, Agisilaus with Pompey, Demetrius with Antony, and others.

Plutarch in his Parallel Lives clearly states that he does not write history nor focuses on recording their most prominent deeds, but rather, through real figures and true situations, he examines their inner world and provides readers with the necessary historical material to understand the characters of these famous men and their moral behavior.

Thus, in a masterful way, Plutarch reflects and intertwines the knowledge of the past with the need for moral revival of nations and leaders, in a time marked by the symptoms of decline.