If The Spirit Of Their Intercourse Were Still The Same After Their Coming Together As It Had Been When They Were Living Apart,' Aristotle Writes, Their Association Can't Really Be Considered A Polis, Or Political Community. 'a Polis Is Not An Association For Residence On A Common Site, Or For The Sake Of Preventing Mutual Injustice And Easing Exchange.' While These Conditions Are Necessary To A Polis, They Are Not Sufficient. 'the End And Purpose Of A Polis Is The Good Life, And The Institutions Of Social Life Are Means To That End.