Calumniae non temere credundum

As you see, flattery and slander were most likely to find an opening when they were framed with reference to Alexander's weak point. In a siege the enemy do not attack the high, sheer and secure parts of the wall, but wherever they notice that any portion is unguarded, unsound or low, they move all their forces against that place because they can very easily get in there and take the city. Just so with slanderers: they assail whatever part of the soul they perceive to be weak, unsound and easy of access, bringing their siege-engines to bear on it

The engines that they use against the hearer are deceit, lying, perjury, insistence, impudence, and a thousand other unprincipled means; but the most important of all is flattery, a bosom friend, yes, an own sister to slander. Nobody is so high-minded and has a soul so well protected by walls of adamant that he cannot succumb to the assaults of flattery, especially when he is being undermined and his foundations sapped by slander.

All this is on the outside, while on the inside there are many traitors who help the enemy, holding out their hands to him, opening the gates, and in every way furthering the capture of the hearer. First there is fondness for novelty, which is by nature common to all mankind, and ennui also; and secondly, a tendency to be attracted by startling rumours. Somehow or other we all like to hear stories that are slyly whispered in our ear, and are packed with innuendo: indeed, I know men who get as much pleasure from having their ears titillated with slander as some do from being tickled with feathers.