Evils of Written Vedas? (apology for cross-posting)

[John Robert Gardner]

Somewhere in a book some while back, i read of a fairly early-dated
tradition wherein it was commonly attested that, for instance, it was evil
to "write the veda's"--in other words, to put them in written form, and
that this fundamentally damaged them due to the import and purity of sound
in recitation.  Aside from praises and lauds of recitation, I was given
to understand that writing them was proscribed due to serious censure
and wrong.  The place I read of this noted, specifically as I recall
it was viz. the UpaniSads.  Does anyone have a traditional text citation
(rather than a secondary source) on this?  The older the better.

Thanks in advance, folks,

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John Robert Gardner
ATLA-CERTR
Emory University
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http://vedavid.org/diss/
"If there is something you're thinking of doing, or wish you could do,
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