What philosophical principle did the early Greeks commonly value as a means of promoting societal ethics?

The philosophical principle that early Greeks commonly valued for promoting societal ethics is altruism. This concept emphasizes selflessness and the well-being of others, suggesting that individuals should act in ways that benefit the community or society as a whole. In ancient Greek philosophy, thinkers such as Socrates and Plato highlighted the importance of virtues and ethical conduct that would contribute to the greater good. The focus on altruism reflected the Greeks' interest in moral responsibility and the impact of one's actions on fellow citizens, fostering a sense of community and ethical behavior.

While other philosophical principles like rationalism or individualism played a role in shaping Greek thought, they did not emphasize the ethical dimensions of concern for others to the same extent as altruism, which encouraged cooperation and societal harmony.