One of the dominant themes of Parallel Livesis the vibrant connection that Plutarch sees between individual action and political destiny. For Plutarch, there is not a public and private construction of the good, where the human being essentially lives two lives. Rather, he seeks to examine individual character in terms of how political fortune is built upon it. The comparison between Greek and Roman exemplars enhances this sense of how character and political fortune are linked to one another. Plutarch is not entirely focused as a historian, as much as he is driven to showcase the need for morality arising from a reflective and subjective notion of the good: "“Let us hope that Fable may, in what shall follow, so submit to the purifying processes of Reason as to take the character of exact history."
Plutarch's entire thematic reasoning in Parallel Lives is to illuminate this condition, one in which "exact history" might not be as important as the morality that binds the present and the past to one another. Political reality is carved out by the individuals whose sense of character reveres the state and sees collective identity predicated upon courage as vital to success. In the parallel notions of Greek and Roman vice and virtue, Plutarch is able to draw out what he considers to be morals that define political success and personal happiness. For Plutarch, being able to evoke these in both sets of "parallel lives" becomes the thematic focus of the work.