Section — Prümmer, Manuale Theologiae Moralis
4. On The Flatterer
106. A flatterer or adulator is said to be he who, by praising, blaming, flattering, moves another to damaging.
Thus, e.g., he is a flatterer who mocks the patience of the injured person; who exaggerates the injury inflicted, saying repeatedly that things of this kind are not to be borne by a noble man; who describes the vileness of the offender, etc., and does all these things to instigate another to revenge. Likewise he is a flatterer who proclaims the utility of theft or damaging. Therefore he who by these or similar modes truly, efficaciously, and formally moves another to unjust damaging is bound to restitution. Nor is it necessary that he directly intend the damage; it is enough that he indirectly wills it, foreseeing that it will follow from his flattery. The things said above concerning the one counseling hold also concerning the flatterer, since he is nothing other than one counseling in a particular mode, namely by flattering, etc.; hence the flatterer is subject to the same obligations as the counselor, provided nevertheless that he truly flowed efficaciously into the damage of another.
Sometimes he who approves or praises an unjust work done is called a flatterer. It is plain that approval of this kind does not induce the obligation of repairing damage, unless nevertheless from it the damager was induced to new injuries or was instigated not to repair the injury already done.