A whole lot of ink has been spilled over the past three decades on the question of whether Murex is the real dye used for tekhelet tzitzit. I’m not going to toss out my two cents, but I do want to make one little suggestion: If you’re thinking of delving into the topic, make sure you’re in the right frame of mind before you get started.

What I mean is make sure you feel you’re prepared to be open-minded and objected, that you don’t have very strong leanings one way or another.

It seems to me that some people set out hoping to be persuaded that Murex is the real thing, whereas others are looking for a good excuse not to change their ways (often for reasons related to socialization).

A few weeks ago I had to travel to the US, where I got to know a local yungerman. He was an accomplished Torah scholar who grew up in New York and had married and relocated to a small kehilah on the West Coast, where he got a job in the local rabbinate. When he heard that I made a living selling tzitzit, he quickly steered the conversation to the topic of tekhelet.

It turns out he was in the midst of collaborating on a book that was very strongly anti-tekhelet. I had a hunch that the arguments he would present to me were nothing new – and I was right.

What I really wanted to know was how he got started out researching the topic. Did he first embark with an agenda? With a hypothesis? Unfortunately I didn’t get an answer out of him on that.

What really surprised me is that he was able to say he was “99% certain” that Murex is not the right source for tekhelet. I could understand had he said 80% certain, but 99%?!?

The reasons he proffered were roughly parallel to the line of reasoning stated by HaRav Asher Weiss. (However, note that even HaRav Weiss is not opposed to wearing tekhelet.)

I keep going over the conversation in my mind, and can’t get over it. For example, he informed me that real tekhelet is “probably not sky blue.” Now certainly there’s room to debate the right hue. Some insist tekhelet is purple, others say midnight blue. But how can you be 99% sure it’s not sky blue? (For example, see here.)

He also said that the chilazon referred to in the Gemara as the source tekhelet was likely a fish, not a snail. Again, you can make a case for such an argument, but there’s also quite a strong case to be made that the term chilazon refers to an aquatic snail. How can you come along and say you’re 99% sure tekhelet dye is not from a snail?

So when that book comes out, I don’t see myself running out to buy it. Maybe I would – if here were just 90% sure.