"Just Be Yourself."

"Frank and natural sincerity is a noble quality, though sometimes harmful to the practitioner.  Dissimulation, on the other hand, is useful and often necessary because men are corrupt, yet it is hateful and ugly, so I know not which to prefer.  I suppose a man might use one procedure as a matter of course without wholly abandoning the other.  That is, in his ordinary and common course of life, he might follow the path of sincerity in order to acquire the reputation of an honest man, and yet, on certain important and unusual occasions, resort to dissimulation.  His deception will be the more useful and will work better because his general good reputation makes him more easily trusted."

(Guicciardini, Ricordi 1.45)

aaah, Renaissance Italians.