Which definition of justice does Plato argue against, stating that it harms enemies?

Plato argues against the definition of justice that equates it with doing good to friends and harming enemies because he sees this view as fundamentally flawed and unjust. In his dialogues, particularly in "The Republic," he emphasizes that true justice cannot be about benefitting particular individuals or groups at the expense of others. This perspective leads to a partial and biased understanding of justice, where the interests of friends are favored while enemies are treated unjustly.

Plato proposes that justice should not be perceived merely as reciprocal relationships based on favoritism or enmity, but rather as a virtue that ensures the well-being of the whole society. Justice, in his view, requires a balance that does not involve harming anyone, which can ultimately disrupt societal harmony and lead to conflict. By advocating for a more universal and equitable approach, Plato encourages a conception of justice that transcends personal affiliations, promoting fairness and the greater good for all individuals within a community.