[Avodah] Chometz: Less than a kezayis

[Zev Sero via Avodah]

On 21/02/17 07:45, Akiva Miller via Avodah wrote:
>
> It has been my understanding throughout whatever little bits of Torah
> that I've been privileged to learn, that if a kezayis of something is a
> shiur d'Oriasa for whatever halacha, then a partial kezayis would be a
> chetzi shiur d'Oraisa, or at least a d'rabanan, for that same halacha. I
> am surprised that chometz (which is generally so very severe!) is an
> exception to this, and becomes mutar when less than a kezayis. The
> reasoning does seem to be that a partial kezayis is not chashuv -- but
> can't that be said about ANY partial shiur? [sarcasm on:] A half-kezayis
> of chazir is not chashuv, so why not eat just a nibble? [sarcasm off]
> What makes chometz different?

Because for most issurim it doesn't matter whether something is chashuv. 
  It's just as assur to eat a neveila's offal as it is to eat its filet 
mignon.  The same is true of chametz, both for eating it and for owning 
it; the point here is not that there's no issur in owning something that 
isn't chashuv, but that something that isn't chashuv is automatically 
batel and therefore *you don't own it*.  It's as if it doesn't exist. 
There's not even any need to explicitly be mevatel it, because it's 
batel by its very nature, unless you explicitly decided to keep it, 
which is machshiv it.

Remember that mid'oraisa bittul of anything is enough to avoid the issur 
of ownership.  Chazal said it's not enough, for two reasons: One might 
find a nice roll on Pesach and think to keep it, thus cancelling its 
bitul; and one might find chametz and absentmindedly eat it.  Neither of 
these reasons applies to a dirty breadcrumb.

-- 
Zev Sero                May 2017, with its *nine* days of Chanukah,
zev at sero.name           be a brilliant year for us all