狗遇狗都是舔人遇人都是演
[gŏu yù gŏu dōu shì tiăn rén yù rén dōu shì yăn]
Roughly translates to 'When dogs meet other dogs they lick each other; when people meet people everyone puts on an act'. Reflects skepticism towards human sincerity, preferring animal instinctive actions.