[Avodah] ID of chilazon vs. chagavim

[Micha Berger]

On Wed, Aug 06, 2008 at 12:08:24PM +0000, Dov Kay wrote:
> See footnote 19 of this article by R. Shaul Yonatan Weingort, originally
> published in Techumin: http://www.tekhelet.com/pdf/bein.pdf. The author
> argues for a distinction between simanim d'oraisa and simanim d'rabbanan.
> The former may be relied upon without a mesora (eg fins and scales in
> fish), while the latter may not (eg birds)...

I would say the distinction is between prescritive and descriptive
simanim. A kosher fish is defined as one that has snapir vekaskeses,
whereas kosher birds to have their simanim in common.

The simanim for chilazon don't define what source may be used for a dye
(IOW, the claim is not that anything that gufo domeh layam etc... can
be used), they are the gemara's description of the source. They are
descriptive, and thus one can argue that they only serve to confirm
a mesorah.

-Micha

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Micha Berger             Zion will be redeemed through justice,
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