Musar for Chullin 230:37
אמר ליה רב מרדכי לרב אשי הכי אמרינן משמיה דריש לקיש
The law of 'orlah shows otherwise'; the argument would then have gone round again, with the result that it [sc. the law of flesh cooked in milk] would have been inferred from the common features [of the others]!<span class="x" onmousemove="('comment',' Thus it was unnecessary to introduce the case of sowing diverse kinds in the vineyard. The argument would then run as follows: Flesh cooked in milk is declared to be forbidden for all purposes by inference from 'orlah by the a fortiori reasoning; if the objection be taken that 'orlah is a special case inasmuch as it had no period of fitness, the reply would be that the case of leaven during Passover clearly shows that this distinctive feature (sc. not having a period of fitness) is not the reason for the general prohibition; and if the objection be taken that leaven during Passover is a special case inasmuch as there is a penalty of kareth attached to it, the reply would be that the case of 'orlah clearly shows that the gravity of the penalty (sc. kareth) is not the reason for the general prohibition; and so the argument would go in a circle: the objection to the case of 'orlah would be met by the case of leaven during Passover and vice versa. What, however, is common to 'orlah and leaven during Passover is that each is forbidden as food and also for all use; the inference then follows that flesh cooked in milk, inasmuch as it is forbidden as food, should also be forbidden for all use. This type of argument, namely, an inference from common features of two or more cases, is very frequent in the Gemara; and the result being satisfactory, it was unnecessary to introduce the third case of diverse kinds in the vineyard.');"><sup>23</sup></span>