亞里斯多德將正義與友誼視為鞏城邦於不墜的兩大德性，然而，此二德性到底如何鞏固政治共同體，長期以來一直困擾著亞里斯多德政治哲學的研究者。本文旨在研究，於何種意義下，正義與友誼維繫政治共同體於不墜。亞里斯多德將正義皆為廣義的正義(全德)與狹義的正義(公平)。本文作者認為，狹義的正義雖足以定分息爭，但廣義的正義才是德亦將友誼分為三種(為了享樂、為了好處、以及為了彼此的善的友誼)，作者認為，為了彼此的善所產生的友誼，才是能進治共同體之良善、達成倫理學與政治學所企求之曘終目的(幸福生活)的德性。過對此二德性的研究，我們可以更清楚地描繪亞里斯多德「德性的政治共同體」計劃之輪廓。顯然亞里斯多德所必儀之共同生活與當代有著相當程度的歧異，也為當代政治生提豐富且寶貴的反省資源。

　　　　　Aristotle takes justice and friendship as the elementary virtues for the consolidation of political communities. This paper aims at examining an intriguing issue which has troubled scholars for a long time: how these two virtues can consolidate the polis?Aristotle divides justice into a broad sense (a complete virtue) and a narrow sense (fairness). I argue that justice, in its broad sense, is the prime virtue to concrete the koin?nia plitikon. Aristotle also divides friendship for each other's good is exactly the virtue to improve the good of polis as well as eudaimonia-to achieve the ultimate end of ethics and political science.Aristotle's project for virtuous community could be outlined much more clearly by studying justice and friendship as the two elementary virtues. It is rather obvious that his expectation of genuine political life differs significantly from the contemporary rival theories. Nevertheless, I believe that the project outlined by Aristotle offers fruitful implications and valuable resources for us to reconsider our political life today.