GEN942 As a sales tactic, making the customer feel food about himself is subject to a restriction.  It enjoys validity only when the compliment or the appreciation the salesperson exudes is sincere.  Should the sentiment expressed amount to nothing more than false praise (hanuppah), the conduct is prohibited.   The condemnation of flattery by Maimonides (Egypt, 1135-1204) is instructive here: “It is forbidden to accustom oneself to smooth speech and flatteries. One must not say one thing and mean another. Inward and outward self should correspond; only what we have in mind, should we utter with the mouth.” [Yad Hazakah [Mishneh Torah], De’ot 2:6] It should not be concluded, however, that engaging in false praise is absolutely forbidden as a sales tactic.  The halakhic prohibition of falsehood is not absolute, and under certain conditions it is suspended.  Examining these exceptions to the prohibition against falsehood, however, will demonstrate that their application to the area of sales practice is very limited.   … darkhei shalom (the ways of peace) does not suspend the prohibition against falsehood unless its purpose is to end conflict or avert the eruption of discord.   If the conduct is merely intended to enhance the quality of human relations, the prohibition against falsehood is not suspected. … Within the framework of the darkhei shalom rationale, engaging in false praise should be legitimate only when the alternative of truth-telling does not better promote peace of mind [See, e.g. Genesis 50:16-17] for the vendee.   This would be the case, for instance, when the vendee does not recall where he bought the articles.   Since he has no recourse to undo or otherwise modify the transaction he entered into telling the truth serves no useful purpose; it only makes the vendee feel foolish.  False praise, on the other hand, helps the vendee make the best of his situation.   Suppose, however, that the vendee does recall where the purchase was made and is a victim of an overcharge or the article has a defect.  Here, false praise is decidedly against the interests of the vendee.   Instead, he should be apprised of his mistake.   CASE 145-6