"Vir prudens non contra ventum mingit" is a latin proverb meaning "A wise man does not pee against the wind".
The figurative meaning (as opposed to the literal, which is quite obvious) is that one should not do something if they do not wish to suffer the consequences. Liveforever prefers this interpretation: "one should not struggle against insurmountable odds."
vir: man
prudens: wise
non: not, or does not if conjugated with a verb
contra: against
ventum: wind
mingit: pee