Debate Responses
A "negative" Mesorah.
The Common Cuttlefish that the Radzyner Rebbe claimed was the חלזון was used throughout the ages as a source for ink. Indeed, the Greek name for cuttlefish, Sepia, is associated with the brown colour of cuttlefish ink144. As we explained on page 31, the תכלת derived from the Murex Trunculus does not have this (negative) “ מסורה ”. To the contrary, we have shown exactly why it was impossible to obtain for nearly a thousand years, and subsequently it was not easily brought back. The forgotten identity of the חלזון and the process of dyeing blue with it were only re-discovered in recent years. The Beis Halevi clearly states that if it could be explained why use of this חלזון ceased, “we would be obligated to wear it”. 145
Bottom Line: The objection of the Bais Halevi to Radzyner Techeiles is actually a support for that of the Murex.
Footnotes
143 הבית הלוי, הובא לשונו בהקדמה לס’ עין התכלת.
144 Wikipedia, Cephalopod ink.
145 גם ראוי להעיר שרוב ישראל נוהגים היום לאכול בשר תרנגול הודו ובאמת, ידוע שאין .)Turkey( לעוף הזה מסורת על כשרותו, וקיי”ל )יו”ד ס’ פב( שלסימני כשרות בעוף צריך מסורת. וא”כ כל מי שאוכלה היום סומך – להקל – על ידע מדעי שאינו דורס, וד”ל.
Murex dyeing until 1453
The fact also is that murex dyeing ended in 1453 during the siege of Constantinople. The reason Jews didn’t wear Techeiles between the 7th and 15th centuries is precisely how the Ramban worded it, that in his time only the Melech Goyim (https://bluefringes.com/archeology/melech-goyim-candidates/) and nobody else wore Techeiles. It’s speculative what the last dye house was used for (possibly to make murex dyed wool for the Pope – one of the candidates) but what’s certain is that non-Jews were still wearing Techeiles when Jews as a whole were forbidden from doing so.
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There are different traditions about what the Beis HaLevi said regarding the Radzyner Rebbe’s cuttlefish: Some hold that he said the chilazon needs a positive mesorah, without which it cannot be identified. (Others hold he said that if there is a fish that everyone knew about throughout the ages, that is essentially a mesorah that it’s not the chilazon.)
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The second tradition mentioned would seem to be the correct one for a number of reasons.
1. That version was recorded and published in the Radzyner Rebbe’s sefer during the lifetime of the Beis Halevi, based on a letter dictated by the Beis Halevi himself, and is also the version quoted by Rav Elyashiv in Kovetz Teshuvos.
2. The first tradition is contrary to the opinion of numerous Rishonim and Acharonim ( מהרי” ל לבוש עולת תמיד חמדת שלמ ה ועוד הרבה ).
