这是对护卫者有私产的推演，看似利己的举动，结果损己又损人。在有限的岁月里，可能看不到“损己”的事件发生，看到的只是永远的胜利。但放长远来说，国不在，“我”的后代何来幸福。

But should they ever acquire homes or lands or moneys of their own, they will become housekeepers and husbandmen instead of guardians; enemies and tyrants instead of allies of the other citizens; hating and being hated, plotting and being plotted against, they will pass through life in much greater terror of internal than of external enemies; and the hour of ruin, both to themselves and to the rest of the State, will be at hand(416-417).
然而，若他们竟私藏宅邸、土地以及钱财，将沦为管家与农民，而非城邦的护卫者；沦为其他民众的仇敌和暴君，而非盟友。他们将深陷“憎恨与被恨，算计与被算计”的困境，终其一生，对国内仇敌敌人的恐惧远甚对外敌的忌惮。如此一来，无论对他们自身，还是对城邦其余民众而言，毁灭危机即刻降临。（第416-417节）

细节解析

1、tyrant: a ruler who has a complete power over a country and who is cruel and unfair暴君
Public opinion is a weak tyrant compared with our own private opinion.《瓦尔登湖》

所在段落

The Story of Philosophy《哲学的故事》第1章Plato第7节VI. The Political Solution第5段第6句：

So much for incompetence; as for rascality we may provide against that by establishing among the guardians a system of communism:
In the fist place none of them should have any property beyond what is absolutely necessary; neither should they have a private house, with bars and bolts, closed against any one who has a mind to enter; their provisions should be only such as are required by trained warriors, who are men of temperance and courage; their agreement is to receive from the citizens a fixed rate of pay, enough to meet the expenses of the year, and no more; and they will have common meals and live together, like soldiers in a camp. Gold and silver we will tell them that they have from God; the diviner metal is within them, and they have therefore no need of that earthly dross which passes under the name of gold, and ought not to pollute the divine by earthly admixture, for that commoner metal has been the source of many unholy deeds; but their own is undefiled. And they alone of all the citizens may not touch or hand silver or gold, or be under the same roof with them, or wear them, or drink from them. And this will be their salvation, and the salvation of the State. But should they ever acquire homes or lands or moneys of their own, they will become housekeepers and husbandmen instead of guardians; enemies and tyrants instead of allies of the other citizens; hating and being hated, plotting and being plotted against, they will pass through life in much greater terror of internal than of external enemies; and the hour of ruin, both to themselves and to the rest of the State, will be at hand(416-417).
浙江大学译本： 假使他们获得了属于自己的住宅、土地和钱财，他们将变成管家或是农民，而不是国家的护卫官；变成其余民众的敌人和剥削者，而不是他们的盟友；他们将憎恨、算计别人，同时也被别人憎恨和算计，他们一生都将在面对内心这个强大敌人的恐惧中度过，这种恐惧远超过他们对外在敌人的惧怕。他们自己和理想国其余民众的毁灭也将指日可待。（第416-417节）

上句见：Day456