 In a letter of 13 November 1639, Descartes wrote to Mersenne that he was “working on a discourse in which I try to clarify what I have hitherto written” on metaphysics (2:622). This was the Meditations, and presumably he was revising or recasting the Latin treatise from 1629. He announced to Mersenne a plan to put the work before “the twenty or thirty most learned theologians” before it was published. In the end, he and Mersenne collected seven sets of objections to the Meditations, which Descartes published with the work, along with his replies (1641, 1642). Some objections were from unnamed theologians, passed on by Mersenne; one set came from the Dutch priest Johannes Caterus; one set was from the Jesuit philosopher Pierre Bourdin; others were from Mersenne himself, from the philosophers Pierre Gassendi and Thomas Hobbes, and from the Catholic philosopher-theologian Antoine Arnauld.