Reference for Pesachim 167:15
ת"ר ועצם לא תשברו בו בו בכשר ולא בפסול ר' אומר (שמות יב, מו) בבית אחד יאכל ועצם לא תשברו בו כל הראוי לאכילה יש בו משום שבירת עצם ושאין ראוי לאכילה אין בו משום שבירת עצם
And he answered him: 'It cannot be defiled', which proves that we decide by the future? - Said he to him: he who pointed out this contradiction to you was not particular about his flour.<span class="x" onmousemove="('comment',' Whether he milled sound wheat or the refuse! I.e., he was careless about his data.');"><sup>12</sup></span> Surely R'Johanan retracted in favour of Resh Lakish['s view], and he said to him: Do not provoke me, for I learn it as the opinion of an individual.<span class="x" onmousemove="('comment',' This refers to the Mishnah in Hul. ');"><sup>13</sup></span>