In our last post, we spoke about geneivat da’at, generating false goodwill, in the context of gid hanasheh. I imagine very few people reading this devar Torah have ever sent a cut-up thigh containing a gid hanasheh to a non-Jew, and fewer still would be able to identify the gid hanasheh even if it was staring them in the face. We can more easily relate to some of the other examples brought by the Gemara of geneivat da’at. These include inviting someone for a meal when you know they will not come, sending gifts to one you know will not accept them, or opening up a barrel of pre-sold wine for a guest (Chulin 94a).
Opening up a barrel of wine for a guest—which leads directly to the rapid decline of the quality of the unused wine—was a clear demonstration of the importance of that guest. However, if one has already sold the barrel to a retailer, the magnanimous nature of this gesture is greatly diminished, as the barrel would have soon been opened in any event. Thus, in order to prevent a violation of geneivat da’at, one must inform the guest that in reality, the wine is not being opened especially for him, lest the guest feel an unwarranted sense of indebtedness to his host.
Of course, one must do so with sensitivity so as not to insult one’s guest; instead of stating, “I’m not opening this barrel in your honour”, one might say, “Let’s make a lechaim...and it just so happens it’s time to open a new barrel of wine”.
The tension between ensuring one does not misrepresent oneself—yet taking care not to hurt the feelings of others—is seen in the following Talmudic story (Chulin 94b). The Gemara relates that Mar Zutra, the son of Rav Nachman, was walking from Sikara to Beit Machoza and Rava and Rav Safra were (coincidentally) walking from Beit Machoza to Sikara. Upon their chance meeting, Rav Nachman, who was clearly flattered by the entourage sent to greet him, exclaimed, “Why did the rabbis put in so much effort to come [and greet me]?” Rav Safra immediately responded, “We did not know you were coming. Had we known, we would have done even more”.
That Rav Safra would respond this way is not at all surprising. Rav Safra, the Gemara notes (and as we discussed here), is the paradigm of one “who speaks truth from the heart”, fulfilling not only his verbal commitments, but even those he merely thought about in his heart. To allow Mar Zutra to think that they had specifically come to greet him was just inconceivable for Rav Safra. Yet Rava said to him: “Why did you tell him this and hurt his feelings?” When Rav Safra responded that by not telling him they would be deceiving him, Rava retorted that Mar Zutra was deceiving himself and hence, there was no obligation to correct his misimpression.
Jewish law accepts the view of Rava. We must go to great lengths not to deceive others, even if we are not the cause of that deception; one can even violate geneivat daat passively. It is only because Mar Zutra had no reason to believe that they were coming to greet him i.e. he was deceiving himself, that no corrective action was needed. As Rabbi Dr. Aaron Levine, zt”l, explains, soon after this chance encounter, Mar Zutra himself would have realized his mistake. After all, had they been coming to greet him, they would have returned with him to Machoza. As they continued to Sikara and he to Beit Machoza, it was rather obvious it was a chance meeting; hence, there was no reason to actually state the obvious and make him feel bad. Realizing his mistake, there would be little reason for him to be upset at Rava and Rav Safra.
At the same time, Rav Safra had no problem stating that had they known Mar Zutra was coming, they would have sent an even greater welcoming party (thereby mitigating whatever hurt Rav Safra might have felt).
Yet can we really trust a person’s self-assessment as to what they might do in any given situation? We tend to have a greater view of ourselves than is warranted and all too often are prone to unjustified claims.
While that may be true regarding an average person, great people of proven moral character are different. And there were none greater than Rav Safra. One who “speaks truth from his heart” can surely be believed to keep the words of his mouth. If Rav Safra said he would have arranged a greater greeting party, you can believe he would have done exactly that.
The Rav Safras of this world are few and far between. In the wine barrel case discussed above, the Gemara notes that Ulla, a second generation amora, once opened a barrel of wine for Rav Yehuda and apparently said nothing, despite the fact that he had just sold the rest of the contents and thus, there was no economic risk in opening a new barrel. While one version of the story justifies his silence as Ulla greatly loved Rav Yehuda, and surely would have opened a new barrel of wine for him in any case, the second version presented by the Talmud claims that, in fact, Ulla did tell him. Even someone of the stature of Ulla could not rely on what he thinks he might have done.
That the Talmudic tractate devoted to the laws of kashrut sees fit to discuss our moral obligations vis a vis our fellow man is no coincidence. Kashrut is more than the food we eat; it must reflect the person we are meant to be.
 Apparently, one is expected to know when a great rabbi is coming to town and by not knowing one runs the risk of disappointing the arriving guest. Or perhaps one can argue that even if there is no way to know who may be coming to town, actively telling someone we did not come to greet you still stings.
 A Talmudic example of such (Jerusalem Talmud, Makkot 2:6) is the obligation to correct those who give honour to someone thinking he knows "two tractates", when in reality he only knows one. Perhaps a more relevant example is telling one's teacher they mistakenly added up their test incorrectly and gave them too many marks. For further discussion, see R. Aaron Levine, False Goodwill in Moral Issues in the Marketplace 3-42. Brooklyn, Yashar Ethics Series, 2005. I highly recommend the many books and articles by my beloved teacher, Dr. Levine, z”l, to whom we all owe a deep debt of gratitude. He almost single-handedly "invented" the field of modern Economics and Jewish Law.
 This issue often arises when making a family simcha, when one sends invitations to people overseas whom one is quite certain will not come. Clearly, if such an invitation is sent only because one thinks those invited will not come, one would violate this biblical prohibition. However, if one would have invited them had they lived locally, then sending the invitation is not only allowed, but most appropriate. Of course, such requires an honest self-assessment, something we biased human beings are not very good at. Yet, as Dr. Levine explains while self assessment is unreliable when great effort is required it may be relied upon in more "simple' cases.