Gottfried Wilhelm Leibniz, Memorandum to Dukes Rudolph Augustus and Anton Ulrich, on the Library at Wolfenbüttel (June 1695)


Here, Gottfried Wilhelm Leibniz (1646–1716) describes the importance of a large scholarly library to both the public good and princely reputation. He encourages the continual acquisition of new works and the preparation of systematic subject and author catalogues. Leibniz served as the librarian of the Herzog August Library in Wolfenbüttel from 1691 until his death. While there, he greatly increased the library’s holdings, created an alphabetical catalogue, and pushed for the construction of a new building that became the famous Rotunda (torn down in the late nineteenth century).


Wolfenbüttel, 4th June, 1695

Since it recently pleased Your Serene Highness graciously to entrust me with the supervision of Your world-famous library, I considered it my duty to reflect upon the contribution which I, for my small part, might make towards Your Highnesses’ gratification, and upon such suggestions as might maintain this splendid ducal library in flourishing state and even enhance it further – both to Your Highnesses’ glory and to common advantage. To this end I thought it necessary to set something down on paper; this I now present with deepest respect.

Now in my opinion, the purpose of a large princely library consists of the two points already mentioned: namely, in its useful service for everyone and in the great renown of the princes themselves who assemble and maintain such a treasury for the common good.

The value of a large library rests on the fact that it is, as it were, a storehouse of all branches of knowledge and information; it can furnish all professions with material on both divine and human or spiritual and secular topics; that is, it will uphold and propagate true religion and piety, interpret the Holy Scriptures, illuminate Church history and elucidate difficult cases of conscience; it will also assist in the exercise of public order and good government, strengthen and enforce the prerogatives of noble rulers and Estates as well as the rights and innocence of private individuals; and, no less, reveal the wonders of God in Nature, the resources and nourishment which flow from them, by means of which health may be maintained or restored and diverse comforts of this life attained; lastly, to preserve and promote [books on] many fine inventions, artifices and buildings, which in times of both peace and war may serve purposes of necessity, use or ornament. In addition to all this, there is the description of times and places, namely history and geography, which provide many splendid examples by means of which the principles or general precepts of the above-mentioned sciences and arts are affirmed and elucidated; to say nothing of languages, rhetoric and poetry, which not only serve a purpose but are also ornamental and give pleasure to all. And since many fine documents and records from ancient repositories are sometimes met with in these books, it may be said that it is as though a printed archive were to be found in a well-stocked library, where information is contained which might often be sought in vain in archives, but may often prove useful in questions of dynastic and public law, genealogies and the like, and even for constitutional purposes.

Since after piety and health nothing is better or more precious among men than understanding and knowledge (which are scattered and divided among many and are to be found together only in a large library), it may be deduced how highly such a treasure is to be esteemed and what glory accrues to noble princes and rulers who hold sway over it; in history their renown has been extolled on this account no less than on account of victories and other great deeds. It is generally known that the incomparable library at Wolfenbüttel is a jewel imparting honour to this illustrious House and Principality; thus, scarcely a scholar or cultured person from this country or abroad passes through this region without seeking the opportunity to visit it.

A major library should be included among those things which cannot be maintained in good condition simply by preserving what is there, but which, like fire and life, must be regularly nourished and augmented, for a library swiftly declines if good, new books are not supplied in sufficient quantity and quality. Thus, to maintain the great renown and usefulness of this Bibliotheca Augusta, it is highly necessary not only to make suitable provision for day-to-day needs, but also gradually to acquire diverse useful works, the purchase of which has been neglected for many years; they are indispensable, for not only does one frequently need them oneself, but also on account of foreigners who ask for them at times. For otherwise people might soon say that this was an old dilapidated library, to maintain or increase which no particular effort was made and which no longer deserved the name of Augusta. And I cannot help pointing out that if matters were to continue thus for some time, this library, formerly of such high repute, might lose its great and magnificent reputation and even fall into contempt. In recent years, in theology excellent commentaries on the Holy Scriptures have been brought out, also unpublished works of the Fathers and many noteworthy dissertations on ecclesiastical history, controversy and practical theology. In jurisprudence there are many court decisions and investigations, practical observations and final rulings in difficult cases, which are often quoted by the judges. There are many useful treatises on the affairs of state of princes and republics, on public and international law; also helpful regulations and information concerning public order, war, justice, finance, commerce, etc., as well as memoranda and political reflections by eminent men of experience. There are splendid new works on physics and medicine, on chemistry and mining, on botany, plants and gardening, on anatomy and zoology, but particularly in medicine there are many significant observations on pathology; also, new authors have made known many remedies to the common weal, which you should certainly have. In mathematics and technology especially, there are many excellent works – on civil and military architecture, optics, dioptrics, astronomy, as well as many fine accounts of fortresses, palaces, statutes, antiquities and other adornments, both new and old, not previously described; many reports on various machines, other arts and utilities of peace and war, which have been usefully practised from time to time and which not only assist private economy, but also serve to increase the revenues of princes and the general livelihood of subjects – in fact, some nations, especially the French and Dutch, have, with the establishment of good institutions, surpassed others in a short time; in such matters the familiar precept: nihil dixi, quod non dictum sit prius has no validity. This can also be said of history, in which every day are brought out not only old records, which so far have not been published, medallions, inscriptions, seals, charters, manuscript chronicles, but also, among modern writings, biographies of great princes, the course of military expeditions, sieges, battles, peace treaties and embassies as well as many other events, and, equally important, manifestos, statements of claims, etc. – all these are particularly indispensable in public affairs. Then, in addition, new works on the geography of the world and individual countries and places, as well as travel books in all languages should justly be acquired, for by this means much new material is revealed every day, which people are accustomed to seek and expect to find in a major library.

Moreover, just as a large warehouse, which contains countless varieties of goods and many kinds of supplies, cannot be exploited without proper inventories and indexes, I have found the library here somewhat lacking in this respect. It is true that the most glorious founder of this excellent library, Your Serene Highnesses’ late Father, not only commenced a magnificent catalogue in which the titles of the books are listed in detail, but continued it for a long while. His in­comparable industry was to his eternal renown, and when, on account of the heavy burden of government, he could no longer attend to the task, he got others to continue it. But, in addition to the main catalogue, in which all books are recorded, certain other indexes and lists are needed to make the use of this great collection simpler, more convenient and extensive. And although above all the alphabetical author-index is essential so that each book may be found quickly, till now it was rendered less efficient by the fact that only numbers are entered against each author’s name, so that it is not made clear which of his books, if he has published more than one, is represented by each number. Thus, for every book one has to go through all the numbers listed against the author concerned and check them in the main catalogue until the book required has been found. So, at first glance, one could not even tell whether the book required was present, less still its location; for this reason we cannot yet be sure of the duplicates. Thus, I have first of all been concerned with remedying this marked disadvantage which is revealed daily and to which little attention was paid at the beginning when the library was not so large. This is at last in progress.

But the best and most valuable aid – namely subject indexes – still remains to be achieved. By their means one can determine the information available and its location, not only in every field of knowledge, but also under every general and special subject-heading, and the authors who treat it in detail. This bears strongly on the chief purpose and use of such an excellent library. Thus, I have long pondered ways and means by which one might achieve such a great and useful task, especially since the catalogues, subject-indexes and so-called classified and systematic bibliographies produced up to now by different writers for the most part fall short of their aim also, by which, as the physical conditions are favourable, it could easily be carried out with the help of several assistants – to say nothing of chronological and other similar indexes. Several men of letters with good university grounding would be needed and also other necessary aids upon which (as upon other matters) I shall not fail to express my humble thoughts at the appropriate time according to Your most gracious pleasure. I do not consider it necessary to reiterate my previous respectful suggestion concerning the publication of some works as a means of making the merit of this library well-known to the world.

Now, as far as the two chief requirements, which have already been mentioned, are concerned, the first, that is the acquisition of good books hitherto missing from the stock, is the most necessary and the most costly, and is common to all large libraries. The sale of duplicates, whose number and designation will be facilitated with the completion of the new alphabetical author-index, could be of some use here. But the second requirement, namely the completion of the proposed subject- or systematic-index, would prove an excellent and unusual contribution to better exploitation, such as cannot be found in any other large library in the world. And by such means one might even emulate the work of Photius – the renowned Photius, formerly Patriarch of Constantinople, left an excellent example of his work in the then Imperial Library and by this means provided a record of many fine books, which are no longer extant, together with some indication of their contents – as nowadays, though without reference to Photius, information on new books is given in the Diaria or Journaux des Scavans and Acta Eruditorum. And I understand that Your Royal Highness, following Your own highly enlightened understanding, has also formed the same decision and intention not only to list, as has already been done with great advantage, but also to describe the books from Your renowned personal collection, the Bibliotheca Rudolphea, within a certain period, from 1517 to 1546, thus illustrating the history of the Reformation. This should also be done in a similar way from the incunabula period to 1517; and then, out of the great Bibliotheca Augusta itself, the books which merit it from 1546 to the commencement of the learned journals. Thus, with God’s help a complete history of scholarship might be achieved in a few years, together with a highly valuable description of this treasury of human knowledge. Such a list would be without parallel in other libraries today, although the glut of books throughout the world will eventually render it a necessity. Thus, if Your Serene Highnesses were to break the ice first in such a way, it would contribute to Your eternal renown and serve as an example to posterity. To this end, in somewhat the same way as those who at Leipzig, by means of their own Collegium Curiosum,[1] compile by their combined efforts the Acta Eruditorum, various scholars from this territory, particularly here at Wolfenbüttel and especially at Your Highnesses’ Academy,[2] would probably co-operate willingly, each according to his own ability, for his own pleasure, advantage and renown.

But above all, as I have said, necessity demands that provision be made for the purchase of good books of which very large numbers are missing; by this means, what one might call the honour and renown of this excellent library will be maintained; to say nothing of the assistants whose help will be necessary if the work on the indexes is to be hastened and not delayed for many years. Therefore in my opinion we should consider a fund for the defrayal of the costs. []

Now it is known that the Bibliotheca Augusta is of great use to the Academy, and professors as well as students and their tutors or instructors derive excellent benefit from it for their studies; therefore, in accordance with the above-mentioned scheme, the library could assist their studies, in proportion to each individual’s industry and learning, for the common good – as is the case in the Italian, French and English academies, colleges and societies; this would provide no small incentive to visit the Academy. It would therefore have to be considered whether the library should not be more closely connected with the Academy, so that the Estates of the Duchy might also contribute to the upkeep of this institution which is a jewel not only of the Court, but also of the Principality, since such a library would not only be a credit to the whole country, but would also be useful, for everyone could satisfy his pleasure and find all sorts of profitable information. As mentioned above, it would contain material to defend the true religion against its adversaries, to administer justice, affirm the rights of princes as well as of individuals, immortalise praiseworthy deeds, keep genealogies of noble families, and, arising from this, stimulate brave spirits to true virtue and glorious conduct, maintain human life and health, assist in the provision of industry, agricultural cultivation and amelioration, the arts of war and peace; to sum up, all necessary or useful knowledge pertaining to household management, church, school or government, so that theologians, philosophers, philologists, lawyers, political scientists, doctors, mathematicians, engineers and even soldiers would find in such a general workshop of human knowledge almost everything that they require, particularly as private individuals cannot or do not always want to buy every work, especially expensive ones, which, as a result of their position or profession, they might often need in the service of the public and their gracious Princes. Thus, what is essentially a universal tool and support of church and school, law and government, might justly be considered by the Estates a matter of no small importance, especially now that the Academy would provide a good opportunity for it.

All this I must in deepest devotion make bold to submit for Your Highnesses’ further enlightened consideration, and shall, for my small part, whenever necessary not fail to provide further humble elucidation upon Your gracious demand;

I remain, always Your most humble and obedient servant, Gottfried Wilhelm Leibniz


[1] Literally: gathering of cultured men, a general term used to designate scholarly societies of the period.
[2] College for young noblemen, founded 1687 by Duke Anton Ulrich. The curriculum included history, mathematics, law, linguistics, rhetoric, riding, dancing and fencing. It was abandoned in 1715 by the Duke’s successor.

Source of English translation: Two Memoranda from Leibniz to Dukes Rudolph Augustus and Anton Ulrich, on the Library at Wolfenbüttel (June 1695); reprinted in Lindsay Mary Newman, Leibniz (16461716) and the German Library Scene. London: The Library Association, 1966, pp. 41–47. Published with the permission of CILIP, The Library and Information Association, U.K.

Source of original German text: Gottfried Wilhelm Leibniz, Memorandum an die Herzöge Rudolf August und Anton Ulrich über die Bedeutung einer wissenschaftlichen Bibliothek (Juni 1695); reprinted in Gottfried Wilhelm Leibniz, Sämtliche Schriften und Briefe. Reihe 1:11, Januar – Oktober 1695. Berlin: Akademie-Verlag, 1982, pp. 60–69.

Gottfried Wilhelm Leibniz, Memorandum to Dukes Rudolph Augustus and Anton Ulrich, on the Library at Wolfenbüttel (June 1695), published in: German History Intersections, <> [September 04, 2023].