Laudator Temporis Acti

Augustine, City of God 2.22 (tr. Henry Bettenson):

But these are external disasters, affecting the body, not the mind, arising from enemy action or from some natural disaster, and I am not discussing these at the moment. I am now concerned with the poisoning of morals, which first decayed slowly and then suffered a headlong plunge. As a result such ruin came upon the commonwealth, even though buildings and walls stood unharmed, that their eminent writers have no hesitation in pronouncing the commonwealth lost.

verum de his adventiciis et corporis potius quam animi malis, quae vel ab hostibus vel alia clade accidunt, nondum interim disputo: nunc ago de labe morum, quibus primum paulatim decoloratis, deinde torrentis modo praecipitatis tanta quamvis integris tectis moenibusque facta est ruina rei publicae, ut magni auctores eorum eam tunc amissam non dubitent dicere.