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Haak, Theodore

Haak, Theodore

(b. Neuhausen, near Worms, Germany, 25 July 1605; d. London, England, May (1690)

learned correspondence, translation.

Haak’s father, Theodor, attended the University of Heidelberg; but little is known about him before he married Maria Tossanus, the daughter of the Reformed theologian Daniel Tossanus (Toussaint), who after escaping the St. Bartholomew’s Day massacre in France became court preacher at Heidelberg and later professor of theology and rector of the university. Through the marriages of his mother’s sisters, Haak was related to a cousin, the Reformed theologian at Leiden, Friedrich Spanheim (1600–1649), and to J. F. Schloer (an uncle), who was counselor of state to Frederick IV, the elector palatine. A grandson of Schloer’s settled in England, where he became a fellow of the Royal Society and of the College of Physicians; it was at his house that Haak died. Thus Haak was closely related to Continental families who were important in the Reformed church, in high state office, and in the learned world at Heidelberg and Leiden. As a conveyor of knowledge and information between England and the Continent, Haak’s long and active life shows the importance of these family connections.

During 1625–1626 Haak studied at Oxford and Cambridge, then returned to Germany. In 1628 or 1629 he took up residence at Gloucester Hall (now Worcester College), then one of the Calvinist centers at Oxford, where he studied theology and mathematics. He left at the end of 1631, was ordained deacon in 1632, and settled in London. During the next few years he was active in the Palatine Collections for the benefit of the exiled ministers of the Palatinate, spending part of his time in Heidelberg. Little is known about his life during the late 1630’s until he settled permanently in England toward the end of 1638, but by 1635 he was in touch with Samuel Hartlib and his circle, probably through his cousins in the Schloer family. In 1656 Haak married Elizabeth Genne, who died in 1669. He and his family were naturalized British citizens late in 1656.

Given his religious views, Haak naturally sided with Parliament during the 1640’s. He undertook a largely unsuccessful diplomatic mission to the Continent Denmark (1643–1644) but later turned down similar offers, preferring to remain in London, where he performed important work as a translator, for example, to the secretary of state, John Thurloe. His services gained him a pension and financial independence. He declined an offer to become secretary to the elector, Charles Louis, at Heidelberg, accepting instead a position as his unofficial agent in London. At this time John Wilkins was the elector’s private chaplain. In 1645 the Westminster Assembly, whose secretary was John Wallis, engaged Haak to make a translation of the Dutch Bible and Annotations, a work that had been prepared at the request of the Synod of Dort. This immense task was completed in 1657, after many interruptions.

In 1647 Haak wrote to Marin Mersenne that the proper use and enjoyment of knowledge lie in its free communication, so that it may serve the general good, in accordance with the divine intent. Twenty years later, in a letter that accompanied a copy of Thomas Sprat’s History of the Royal Society, Haak wrote to Governor John Winthrop of Connecticut about the need for mankind to improve “the treasures God hath communicated to them so abundantly throughout all the world,” thus “more and more reconciling the estrangedness of the minds of mankind amongst themselves, that they may be willing to listen to more and more and still better Truths and Union.” He hoped that the History would not only “revive and quicken” the governor himself to mind his “engagement and interest,” but that he in turn would “excite and animate many others also to consort and cooperate for the advancement of so universal a Benefit as the scope of this Society holds forth, and their endeavours promise to all the world.” In these words Haak stated the aspirations that were shared by Hartlib’s Comenian group and by the members of the early Royal Society, two groups which show considerable overlap. Natural philosophy, i.e., the study of God’s manifest revelation in creation, is an ennobling activity; it leads to piety, peace, order, and a sense of community among all mankind. The study of natural philosophy is the crucial prerequisite for the successful achievement of Comenian pansophy.

When Comenius arrived in London in September 1641, he was received by Hartlib, Joachim Hübner, John Pell, John Dury, and Haak. At that time Haak had already served Hartlib and his Comenian scheme. Late in 1639, through his command of French, Haak initiated a correspondence with Mersenne, then widely known as the chief figure in a group that was dedicated to the discussion and exchange of learned and scientific knowledge. The first letter was accompanied by copies of Comenius’Pansophiae prodromus (1639) and Pell’s Idea of Mathematics, and both authors now began to correspond directly with Mersenne. Unfortunately we do not have Haak’s letters; but the nineteen letters from Mersenne to Haak, written within little more than a year, show a lively exchange of books and information on the sorts of subjects that interested Hartlib and that later figured both in the early scientific meetings in England before 1660 and in the Royal Society after that date.

There is therefore good reason to accept John Wallis’ account, although written many years later, that it was Haak who at London in 1645— “if not sooner” — “gave the first occasion, and first suggested those meetings” which have the best claim to be considered the beginnings of “the Royal Society of London for improving Natural Knowledge.” In May 1647 Haak resumed his correspondence with Mersenne, who had been traveling extensively in Italy and France for much of the time between October 1644 and the early part of 1647; four more letters followed until July 1648, although it is not clear whether Mersenne answered. (He was ill much of that time and died on 1 September 1648.) Haak’s letters appear unmistakably related to the scientific meetings then being held in London, for he refers to experiments being performed by a group of which he was a member.

During the following years Haak was busy with translation and was in touch with Pell, Hartlib, and Duty, among others. Within a year of the first meeting of the as yet unnamed Royal Society, Haak was proposed for membership by John Wilkins, thus becoming an original member of the Society. Less than a year later, in late August 1662, he received a letter from his old friend, the Leiden philologist J. F. Gronovius, “expressing his high sense of the usefulness of the design of the Society” (Birch, I, 108). It was Gronovius who in 1639 had taken Haak’s letter with Pell’s and Comenius’ books to Mersenne in Paris. Until the end of his life nearly thirty years later, Haak regularly attended the meetings of the Royal Society, from time to time serving on various committees. He made a few communications but was chiefly active in the promotion and maintenance of correspondence with the learned world abroad, especially in Germany. He proposed a considerable number of visiting Germans for membership, he translated letters, and about 1680 he acted as intermediary in the correspondence between Hooke and Leibniz.

During the last two decades of his life, Haak was very close to Hooke; for periods of several years they saw each other at least once a week, sometimes eating or drinking tea together, holding conferences with learned friends, and playing chess. Like Hooke, Haak appears to have taken a special and continuing interest in that old Comenian project, a universal language. Haak and Hooke also talked much about books and book purchases. Haak had known Milton since the late 1640’s when both did translation work for the Council of State. He began but seems never to have finished a translation of Paradise Lost into German.

Haak’s own letters and writings tell us very little about himself, and our knowledge of his private life is sparse; but all his contemporaries agree that he was an exceptionally kind-hearted and generous man. By virtue of his work, beliefs, and activities, he charted a well-nigh archetypal course during a long life that covered most of the seventeenth century.


I. Original Works. Among Haak’s translations are German versions of two pieces by the Puritan divine, Daniel Dyke the Elder: The Mystery of Self-Deceiving (London, 1615), in German under the title Nosce teipsum (Basel, 1638); and a Treatise of Repentance (London, 1631), in German as Nützliche Betrachtung … der wahren Busse, first published with Nosce teipsum (Frankfurt, 1643). Both were several times reissued together in German. The important Mersenne correspondence is in Cornelis de Waard et al., eds., Correspondance de Marin Mersenne (Paris, 1932– ), VIII (1963), IX (1965), X (1967), XI (1970), and in future volumes. Two of the letters from 1647 and 1648 re in Harcourt Brown, Scientific Organizations in Seventeenth Century France (Baltimore, 1934), pp. 268–272. The letters to John Winthrop are in “Correspondence of the Founders of the Royal Society With Governor Winthrop of Connecticut,” in Proceedings of the Massachusetts Historical Society 1878, 16 (1879) 206–251. The Haak-Hooke-Leibniz letters have so far been only partially published: see C. I. Gerhardt, ed., Die philosophischen Schriften von G. W. Leibniz, 7 vols. (Berlin, 1875–1890), VII, 16–20. There is also material relevant to this correspondence and to Haak in general in the letters of Johann von Gloxin to Leibniz, Sämtliche Schriften and Briefe, 1st ser., Allgemeiner and historischer Briefwechsel, III (Leipzig 1938). Haak’s activity in the Royal Society can be traced in Thomas Birch, The History of the Royal Society, 4 vols. (London, 1756–1757).

II. Secondary Literature. There is an excellent monograph by Pamela R. Barnett, Theodore Haak, F. R. S. (1605–1690) (The Hague, 1962). The bibliography gives a full listing of the primary sources, both unprinted and printed, and of the secondary material; this book also presents the first printing of the translation of Paradise Lost, which covers bks. I-III and the opening lines of bk. IV. Miss Barnett’s solid scholarship and good insight into the period transcend much recent but inferior writing on the events in which Haak was involved. Her “Theodore Haak and the Early Years of the Royal Society,” in Annals of Science, 13 (Dec. 1957), 205–218, is also commendable.

Useful and suggestive information about the German intellectual milieus with which Haak was in touch will be found in Leopold Magon, “Die drei ersten deutschen Versuche einer Übersetzung von Miltons ‘Paradise Lost,’” in Karl Bischoff, ed., Gedenkschrift für Ferdinand Josef Schneider (Weimer, 1956), pp. 39–82. Among much inferior writing on the subject, R. H. Syfret, “The Origins of the Royal Society,” in Notes and Records. Royal Society of London, 5 (Apr. 1948), 75–137, still stands out as basically sound and reliable. Birch’s History should be supplemented by Henry W. Robinson and Walter Adams, eds., The Diary of Robert Hooe 1672–1680 (London, 1935); and R. T. Gunther, Early Science in Oxford. The Life and Work of Robert Hooke, X (Oxford, 1935) pp. 69–265, the diary from Nov. 1688 to Aug. 1693.

Hans Aarsleff

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