Commentary for Niddah 45:5

מופנה מצד אחד לרבי ישמעאל למדין ואין משיבין לרבנן למדין ומשיבין

what is the practical difference between one whose one term is available for deduction and one none of whose terms is available for deduction? — The practical difference between them is the case where you find a <i>gezerah shawah</i> one of whose terms is available for deduction and another none of whose terms is available for the purpose, and neither the one nor the other can be refuted, in such a case we must leave the one neither of whose terms is available and make deduction from the one of which one term is available. But what refutation is there in this case?<span class="x" onmousemove="('comment',' The analogy (supra 22b) with man. Sc. since, as was explained supra, the only reason why deduction is made from a gezerah shawah both of whose terms are available for the purpose in preference to one of which one term only is available is the consideration that while the latter can be refuted when a logical refutation is offered the former cannot be refuted even in such a case, it follows that where no refutation can be offered it is immaterial whether the deduction is made from the one or the other. And since R. Meir (supra 22b) preferred the gezerah shawah between man and beast (both of whose terms are available) to that of man and sea-monsters (whose one term only is available) he must have intended to avoid thereby a refutation that had suggested itself to him. Now what was that refutation? ');">⁵</span>

Explore commentary for Niddah 45:5. In-depth commentary and analysis from classical Jewish sources.