Reference for Bava Batra 42:12
וניחוש דילמא אתי לאיתרשולי אמר ליה)
Said Rabina to Raba: May we say that R. Huna adopts the same principle<span class="x" onmousemove="('comment',' Viz., that one man must not interfere with another's livelihood. ');"><sup>10</sup></span> as R. Judah? For we have learnt: R. Judah says that a shopkeeper should not give presents of parched corn and nuts to children, because he thus entices then, to come back to him. The Sages, however, allow this! — You may even say that he is in agreement with the Rabbis<span class="x" onmousemove="('comment',' I.e., the Sages just quoted. ');"><sup>11</sup></span> also. For the ground on which the Rabbis allowed the shopkeeper to do this was because he can say to his rival, Just as I make presents of nuts so you can make presents of almonds;<span class="x" onmousemove="('comment',' And therefore I am not interfering with your chances, ');"><sup>12</sup></span> but in this case they would agree that the first man can say to the other. 'You are interfering with my livelihood.'<span class="x" onmousemove="('comment',' And therefore must not set up next to me. ');"><sup>13</sup></span> An objection was raised [against Rab Huna's ruling from the following:] 'A man may open a shop next to another man's shop or a bath next to another man's bath, and the latter cannot object. because he can say to him, I do what I like in my property and you do what you like in yours?' — On this point there is a difference of opinion among Tannaim, as appears from the following Baraitha: 'The residents of an alley can prevent one another from bringing in<span class="x" onmousemove="('comment',' I.e., from letting an apartment to. ');"><sup>14</sup></span> a tailor or a tanner or a teacher or any other craftsman,<span class="x" onmousemove="('comment',' If there is already one in the court. ');"><sup>15</sup></span> but one cannot prevent another<span class="x" onmousemove="('comment',' Lit., 'his neighbour'. ');"><sup>16</sup></span> [from setting up in opposition].' Rabban Simeon b. Gamaliel, however, says that one may prevent another.<span class="x" onmousemove="('comment',' R. Huna is thus in agreement with R. Simeon b. Gamaliel. ');"><sup>17</sup></span> R. Huna the son of R. Joshua said: It is quite clear to me that the resident of one town can prevent the resident of another town [from setting up in opposition in his town] not, however, if he pays taxes to that town — and that the resident of an alley cannot prevent another resident of the same alley [from setting up in opposition in his alley].<span class="x" onmousemove="('comment',' According to the view of the Rabbis just given. ');"><sup>18</sup></span> R. Huna the son of R. Joshua then raised the question: Can the resident of one alley prevent the resident of another [from competing with him]?<span class="x" onmousemove="('comment',' Would the Rabbis put him on the same footing as a resident of the same alley or not? ');"><sup>19</sup></span> — This must stand over. R. Joseph said: R. Huna agrees that a teacher cannot prevent [another teacher from setting up in the same alley], for the reason mentioned,