The second shiur in Rav Daniel Wolf’s מנחה טהורה is on the classes of methods by which objects become tamei. The Rav offers 3 options:
The object is defined by the Torah as a source of tuma.
The classic example of this are all the avot hatuma defined in the torah: a dead body, a sheretz met, etc.
Tuma was passed from one object to another.
The classic examples are the basic methods of passing on tuma: a person touching a sheretz met, for example.
A less common type of tuma. Here, the tuma is passed by association. The object becomes part of the same whole as the tamei object and thereby becomes Tamei, even though there wasn’t a formal Haavara.
Rav Wolf brings a number of examples, some more clear-cut than other: There’s the mishna in Taharot 1:9 where pure food becomes connected to food that is rishon and it also becomes rishon. Also, kelim that become tamei from being inside Ohel Hamet may be in this category.
Which class is it?
So there are the clear-cut cases, but then there are also the unclear ones. Much of this chapter in the book is dedicated to the unclear ones, and there are also references to later chapters where this chakira arises in other cases.
One of the clear-cut cases of Haavara that Rav Wolf mentions is a person who touches a dead body, Avi Avot Hatuma, and becomes tamei at the level of Av Hatuma. It seems clear enough: the person touches a dead body and the Tumat Met transfers to them at a lower level.
|Cherev Kechalal: a simulation|
It seems to me that we could ask the same question about a person who touched a dead body. Did they absorb the existing tuma, or is there something in the experience of coming in such close physical contact with a corpse that creates a new source of Tumat Met?
Admittedly, it’s a bit of a chiddush to say that we can have Tumat met that doesn’t pass directly from the dead body. Then again, that’s essentially what Rav Wolf is saying about Cherev Chalal so I don’t see a big difference. That said, I’m still just getting into these sugiot, so maybe I’m missing something…