On Leibniz: Expanded Edition

21. Leibniz Disillusioned Parting Ways from J. D. Crafft

385 Johann Daniel Crafft or Krafft and sometimes Kraft (1624–9 April 1697) was for many years Leibniz’s collaborator and business partner. And not just that—he was as close a personal friend as Leibniz ever had. By profession Crafft was a chemist, alchemist, and scientific entrepreneur . The two had been in touch ever since Leibniz’s mid-twenties when, like Crafft, he was in the service of the Elector of Mainz. Their regular, extensive, and long-enduring correspondence dates back to the summer of 1671, when they began to scout out opportunities for using science to make money.1 They soon even agreed on a monoalphabetic cipher (based on the keyword Labyrinthus) to foster the confidentiality of their exchanges.2 Over time their joint projects included such entrepreneurial ventures as the cultivation of silk, the manufacture of glass, extracting steel from iron, distilling brandy, refining sugar, and making phosphorus. At times Crafft derived considerable success from such projects—in 1674 he had founded a promising silk works in Saxony.3 Although an enterprising entrepreneur, Crafft was neither a good judge of character nor an adept manager of business affairs and was eventually driven into impoverishment. The Crafft-Leibniz correspondence extended over the quarter-century of their collaboration, and they exchanged many scores of letters. And their contacts were not confined to the epistolary mode. Each traveled extensively and on numerous occasions they seized the opportunity of personal contact and interchange. In October 1694 Crafft departed his home in Arnstein for Holland, leav-  21 Leibniz Disillusioned Parting Ways from J. D. Crafft 386 leibniz disillusioned ing wife and family behind. (He was never to see them again.) He settled in Amsterdam where he was soon joined in early November by Leibniz, who absented himself from Hanover without official leave. There they concerted plans for various business ventures, in particular a petition to William of Orange (William III in Britain) for a licensed monopoly to manufacture brandy in the Netherlands by a process they had long devised.4 In late November Leibniz returned to Hanover via Arnstein, perhaps to reassure the now deserted Mrs. Crafft and to arrange for her to ship some five wagon-loads of copper to Hanover.5 For a brief time—from December 1694 to January 1695—Crafft sent Leibniz some letters regarding his activities and various business projects, principally relating to brandy.6 But then he fell strangely silent with only a long apologetic communication in late April,7 a cursory note in late May,8 and a contritely apologetic note in June, excusing inactivity by gout and pleading for “a little patience” (ein kleine gedult).9 Finally in July Leibniz wrote him a brief letter of bitter complaint and recriminations.10 At this point the correspondence lapsed for over half a year, and Crafft was not heard from again until February of 1696, when he sent Leibniz a long letter full of apologies and excuses but also reporting activity regarding some of their pet projects: sugar refinery, brandy making, lottery ventures, salt making, windmills, and the like.11 This elicited an irate response form Leibniz in March, again voicing complaints, reproaches, and recriminations but also entering into a brief substantive discussion regarding water mills and pumps.12 But now there ensued another long silence before Crafft responded on September 1696 with a long letter in which he pleaded for funds to extract him from financial difficulties.13 And he soon followed this up with another brief communication in the same sense.14 Crafft’s next—and last—letter to Leibniz, 30 September 1696,15 acknowledges “my foolish habit (in which I am my own enemy) not to write you until then is some accomplished work to report” (meine narrische Gewohnheit [worinne ich mir selber feind bin] mir vorgenommen nicht zu schrieben, biss ich solches ins werk gestellet).16 In the body of the letter, a somewhat incoherent discussion involving business matters gets mixed with sad commentaries on Crafft’s state of ill health. At this point Leibniz more or less gave up on Crafft, and their correspon- leibniz disillusioned 387 dence fell into abeyance until Leibniz finally wrote Crafft in March 1697, replying to his letter of September 1696 with a long communication replete with complaints and reproaches.17 The letter is an extraordinarily detailed bill of particulars, surveying Crafft’s offences against Leibniz as something of a legal brief in an...