Martin, welcome to the show. How are you?

Thanks for having me, Steven.

It's my pleasure. Maybe you can describe to our viewers and listeners what it is that you do.

Well, I'm an English professor. I teach at Harvard. I'm also a writer.

And the book we are talking about today is not primarily an academic book or it mixes

an academic subject, the history of a secret language that was spoken in central Europe

with a family story. So it's for me, also kind of unusual experiment.

Tell me about the family connection.

Well, so growing up, I knew that my great-grandfather, you know, I grew up in Germany.

I knew that my grandfather was in the war,

worked, you know, fighting for the Viermacht. He was a relatively young man.

And that's all I knew. And then by chance, in the 90s, at the great library at Harvard,

in Widener Library, I was sort of looking for family stuff, sort of at random, really to procrastinate.

I didn't want to write my dissertation. And I found this track by, he became as a historian,

my great-grandfather. And I found this absolutely vile, anti-Semitic track. He had written

in the 30s. And that's absolutely shocking to me. I didn't realize that he had any connections

to the Nazis. And what was, it was shocking, but it was surprising that in that track,

he talked about language a lot. He was a historian of names, of family names, genealogies.

And in that track, he wrote about how Yiddish, the particular form of German spoken by many

Eastern European Jewish people, was somehow sullying the purity of the German language.

And in the course of talking about that, he also talked about a secret language called

Rockbells, the incomprehensible, the can of beggars, that I knew had become incredibly important

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