The Correspondence with Arnauld
Leibniz’s correspondence with Antoine Arnauld took place in his so-called “middle period”: it began in February 1686 and ended in March 1690, when Leibniz wrote his final letter to Arnauld. The exchange was initiated by Leibniz, who sent Arnauld a short summary of his most recent philosophical composition, the “Discourse on Metaphysics”, and asked Arnauld for his opinion. The ensuing correspondence is an excellent source of information about Leibniz’s views in the middle period: it contains a thorough, clear, and surprisingly systematic presentation of many of his most important philosophical doctrines. This chapter focuses on what we can learn from these letters about Leibniz’s theory of complete concepts, his account of body and substance, his doctrines about causation, and finally his theory that minds have a special status in God’s plan.