If someone insists to you that he is not very nervous, only a little nervous — that he is only a little bit over the hill, but certainly not old and used up — and keeps insisting this, with compulsive loquacity, you quickly recognize whistling in the dark. But what if four people are doing that at once?

Such is the start of “Herz Schmerz ,” a modestly funny, modestly touching collaboration between the choreographer John Heginbotham and the author-illustrator Maira Kalman that had its premiere at the Baryshnikov Arts Cente r on Thursday. The recited text about nerves is by the Swiss writer Robert Walser (1878-1976), and it immediately establishes Walser’s distinctive comic-depressive tone.

But the four people talking together also signal how the show, in theatricalizing Walser, swerves from him. He was among the most solitary of writers. “Herz Schmerz” is a gathering of friends.