Mathematicians divide

One of my fine graduate courses at Hunter College was a "World Poetry" course taught by William Pitt Root.  One of our texts was Against Forgetting:  Twentieth-Century Poetry of Witness (W W Norton, 1993), edited by Carolyn Forché.  In this collection is found "To Myself," a poem that confronts fear, by Abba Kovner (1818-1987), a hero of anti-Nazi resistance. Kovner dares to open the poem with the word "Mathematicians."