“A single professor often has such an influence on the province that one is astonished. He educates schoolteachers. The dealings of scholars have an influence even on generals and ministers of government, on the city and on the country, making everything yield a dividend. The capital which he invests brings a thousand-fold profit.”
— Theodor Gottlieb von Hippel [bio] [Samtliche Werke, 12: 23]
The teaching staff at German universities during the 18th century consisted of lecturers (Privatdozenten), associate professors (außerordentliche Professoren), and full professors (ordentliche Professoren). (See a list of full and associate professors at Königsberg during the 18th century, as well as a table of full professors at German universities.)
The full professorship functioned much like an endowed chair in that it was more or less a guaranteed position within the structure of the university, and the university administration (academic senate, rector, chancellor, faculty deans [more]) was drawn from this body of full professors. Associate professors were paid less than full professors (and often not at all), they had no voice in administrative affairs, and the positions themselves were ephemeral, created and disbanded as needs or opportunities arose. Turnover among associate professors was more than twice that of full professors; associates were either biding time until a full professorship opened, or else their teaching was merely a second job. Recruitment to full professor was generally internal, unless specific individuals elsewhere were being sought (such as when Erlangen pursued Kant). There were no “national searches” to speak of, and advancement typically depended upon the professor’s popularity in the classroom, rather than scholarship.
Full professors, and usually the associates as well, were required to give public lectures (that is, the lectures were free to attend): at Königsberg, full professors were required to lecture publicly for four hours per week, the associate professors only two hours. Lecturers, on the other hand, gave only private lectures, and here students were required to pay a pre-determined honorarium directly to the instructor at the end of the semester (a fuller discussion is found under Academic Instruction). Lecturers received no salary for their teaching, the only income being these honoraria, although they often held other jobs, either within the university, such as Kant’s side-job as an assistant librarian, or else as a pastor or teacher at one of the local churches or schools. Occasionally a respectable lecturer of long-standing would be made an associate professor without pay if there was not yet a full professorship available. Similarly, individuals would sometimes be made honorary professors in order to mark some achievement or distinction, and this would come with neither pay nor responsibilities. Finally, there was also a distinction between those professorships that were permanent and those created especially for an individual and that would dissolve upon that person’s retirement or death [Paulsen 1906, 80].
The philosophy faculty at Königsberg during Kant’s day (and since its founding in 1544) included at least eight full professorships, that by the 18th century consisted of chairs in Logic and Metaphysics, Practical Philosophy (ethics, natural law, international law), Rhetoric and History, Poetry, Greek Language, Oriental Languages, Mathematics, and Physics. There were occasional additions to this group of full professors; for instance, a chair of “German Rhetoric” was established from 1743 to 1759, filled by Christian Cölestin Flottwell [bio], a chair in Literary History was filled by Coelestin Conrad Neufeldt [bio] from 1724-1750, and a chair on Antiquity was filled by Gottfried Bernhard Casseburg [bio] from 1739-50. There were also a small and varying number of associate professors assigned to the philosophy faculty, sometimes given a specific discipline (such as Knutzen [bio], as an associate professor of logic and metaphysics, or Deutsch [bio] as an associate professor of church history and oriental languages). See Philosophy Faculty at Königsberg for a complete listing.
Three separate public ceremonies marked the creation of these lecturers and professors: (1) their graduation from the university with a magister degree (in philosophy) or doctoral degree (in the higher faculties), and which involved the dean, and the candidate giving brief Latin addresses, (2) their habilitation, which concludes with a pro receptione disputation and gives the individual the right to teach at the university (magister legens), and (3) their inauguration as new professors (either associate or full), concluding with a pro loco disputation. (See accounts of Kant's graduation and habilitation and of his inauguration and pro loco disputation.) Many individuals remained lecturers their entire career and so never gave a pro loco disputation, and occasionally an individual would skip the lecturer stage altogether, having received a professorial appointment right after graduation but even these lucky few needed to habilitate as well as participate in a pro loco disputation. So, everyone who teaches must graduate and habilitate; and whoever assumes a new professorship must also carry out a pro loco disputation.
 See McClelland [1980, 81], and see Clark’s informative discussion of hiring practices [1986, 367-77]. In his description of the university at Königsberg, Goldbeck [1782, 36-37] distinguishes between “königliche Professoren” and “akademische Privatlehrer,” noting that none of the full professors at Königsberg are unsalaried at the moment and that there is only one associate professor (who are always unsalaried Goldbeck must be referring here to G. C. Pisanski, who spent his entire teaching career as an associate professor of theology). On the emergence of the professorial positions in the late middle ages, see Clark [1986, 361-69].
 An example from Königsberg of the latter is C. C. Flottwell (1711-1759), appointed in 1743 to a newly-established chair of German Rhetoric that was discontinued at his death. A more unusual example is that of C. C. Neufeldt (died 1750), who essentially bought himself an associate professorship (in literary history) in 1724; G. F. Rogall’s scathing account of this incident is given in Neufeldt’s biographical entry).
 The original statutes for the Albertina of 1546 and 1554 [reprt. in Arnoldt 1746, i.173-92, Appendix #49], show that ten professorships were intended for the Philosophy Faculty, namely Hebrew, Physics, Greek, Rhetoric, Dialectic, History and Ethics, Mathematics, Poetry, Latin, and an Inspector of the Alumnat. This is similar to what we find in the 18th century, although by then history is combined with rhetoric, dialectic is now called logic and metaphysics, Latin is taught by the professor of poetry as well as various lecturers, and the inspector duties were assigned to the professor of mathematics (because of the location of the observatory, which he oversaw).
[Pozzo also notes that the 1770 “Methodological Directions” from the government required a six-fold division in the philosophy faculty: (a) philosophy, (b) mathematics, (c) economics, (d) aesthetics, (e) political history, and (f) philology. Actual course announcements indicate that the faculty was divided into five departments, since aesthetic subjects were included in philosophy and philology.]
Most universities were arranged with four faculties: philosophy, plus the three higher faculties of theology, law, and medicine. Graduation was possible from any of them. A graduate of the philosophy faculty became a Doctoris Philosophiae seu Magistri a “doctor of philosophy or magister,” although he was commonly called a Magister (designated by an M.’ printed before one’s name) and a graduate from any of the higher faculties was called a Doctor (designated by a D.’ printed before one’s name). The words themselves are nearly synonymous: a magister is one who teaches, and a doctor is one who has been taught. But some of the differences were real enough. Clark reports, for instance, that in the middle ages doctors, but not magisters, enjoyed immunity from torture [Clark 1986, 531-34], and we find in the 18th century some interest on the part of magisters to call themselves doctors (such was the occasion of a censure from Minister von Printz, dated 19 April 1712, and directed at J. S. Strimesius [bio], the newly appointed full professor of rhetoric and history)[Bornhak 1900, 89]. One practical difference, at least at Königsberg, was that doctors were required to publish their doctoral dissertation, while magisters were not. It should also be noted that while the graduation of magisters and doctors involved a public ceremony, there was no public disputation or defense of the dissertation (contrary to Bornhak’s claim [1900, 91]).
At Königsberg in the 18th century, the philosophy faculty awarded only the magister degree, while the three higher faculties awarded the doctor degree; it was only towards the end of the century that we also find people being awarded doctorates in philosophy, coinciding with the gradual erasure of the distinction between the higher and lower faculties. This distinction appears to have turned on the function of the faculty: the higher faculties were considered professional programs for the production of pastors, lawyers, and physicians, and these were Doctors having learned, they were ready to practice their arts. In the wake of the increased attention given to primary and secondary education, the philosophy faculty was gradually professionalized by inheriting the task of creating a professional class of school teachers, who hitherto had been pastors and cantors employed at some church, or else theology graduates waiting for a pastoral position. Once this educational reform got underway, the philosophy faculty was seen not merely as preparing students for the three higher faculties, but as preparing professionals of their own: thus the doctorate in philosophy [Bornhak 1900, 138-39].
Of course, most students at the university did not graduate at all, instead attending those courses they thought most helpful to their careers, with three years being the normal period of study. Of those graduating, most would do something other than teach at a university, working instead as pastors or church officials, lawyers, physicians, or whatever. The large majority of magisters were theology students [Bornhak 1900, 90].
At Königsberg, graduation from the philosophy faculty involved four steps: (1) the presentation of a Latin treatise to the philosophy faculty; (2) the defense, which was a private oral examination with one or more of the faculty, or perhaps simply with the dean (we lack any description of these affairs); (3) the payment of fees for the conferral of the degree; and (4) a public conferral of the hood, at which time the dean of the philosophy faculty might give a speech, and the new Magister might make a few remarks, after which there might be some music or other amusements before heading off to the post-graduation party.
One was allowed to teach only in that faculty for which one had a degree, and heavy fines were indicated for violators. A professor from one of the higher faculties could hold private lectures in philosophy only if he had been awarded a Magisters from a philosophy faculty. Similarly, and more commonly, one would often find Magisters lecturing in the philosophy faculty, who eventually received a doctorate in one of the higher faculties, and then offered courses there as well (about one-sixth of all the philosophy faculty at Königsberg in the 18th century did something like this). A final requirement for teaching at Königsberg: one must belong to the Lutheran confession [Goldbeck 1782, 35].
Of course, if the faculty approved of one’s courses being offered, the actual degree was of less importance; and if the faculty did not want you teaching there, then having the degree was of little help for instance, J. B. Hahn, Sr (1685-1755) was a full professor of oriental languages at Königsberg when he received his Doctor of Theology from the university at Greifswald in 1717, but in the 38 years left in his teaching career, he never offered a course in theology. Students also tried to influence the hiring of professors [Bornhak 1900, 19].
 Bornhak also notes that Minister von Zedlitz decided in 1771 (edict of June 9) that anyone wanting to graduate as a magister and a doctor was essentially receiving two degrees, and therefore needed to pay the fee for each. In general, Bornhak reports that the magister title was seen as an antiquated holdover from the middle ages [1900, 90]. In some universities other than Königsberg, one would find a Doctoral degree in philosophy (the lower faculty); Friedrich Theodor Rink was presumably the first to receive a doctoral degree in philosophy at Königsberg (1788 or 1789). An extensive discussion of the rise of the Ph.D of D.Phil. in German universities can be found in Clark [2006, 183-201].
 This has the immediate result that the graduation of doctors left behind more traces in the historical record. Kant’s Latin treatise for his Magister degree (De igne, 1755) was never published in his lifetime.
 At the same time, the distinction seems quite arbitrary. In the Lecture Catalogs, the professors of the three higher faculties were given the title “Dr.” or “D.” while those from the philosophy faculty were given the title “Prof.”, at least until the mid-1790s, when they were all given the title of “Dr.”
 Goldbeck [1782, 80-1] describes the philosophy examination as being conducted first privately by the dean and then by all the members of the faculty in the senate. This private examination was followed by a public examination, which could last as many as three days and to which all the professors, doctors, and magisters were invited, both to listen and to ask questions. This public examination was disbanded in 1717, such that by Goldbeck’s day it was little different from that administered in the higher three faculties. Philippi claims that Georg Christoph Pisanski (1725-1790) described his own examination and graduation (1759) ceremony in his Lebenslauf.
 A decree signed by v. Tettau, v. Schlieben, and v. Wallenrodt, dated October 23, 1745, and addressed to the academic senate concerns “the reception [habilitation] of magisters who graduated from another university.” It states that henceforth such magisters will be charged 25 rthl. “pro receptione” rather than the usual 8 rthl. [repr. in Arnoldt 1746, ii.75-76, Appendix #53].
By Kant’s day, there were three kinds of public disputations: the first two (pro receptione and pro loco) involved a change in status at the university, while the third was required as part of the duties of all professors. Kant’s pro receptione disputation was his New Elucidation (1755) [writings], the pro loco was his Inaugural Dissertation (1770) [writings], and the only example we have of the third kind of disputation is his Physical Monadology (1756) [writings], although professors would often have several of these, especially earlier in the century.
The pro receptione disputation marks the passage of a graduate into the teaching faculty. Those desiring to teach at the university must not only graduate (as a Magister) but also habilitate (as a Magister legens). Typically this was done in the same faculty as one intended to teach, and required three things: (1) the presentation of a Latin treatise to the appropriate faculty, (2) the publication of this treatise by the university printer, and (3) a public defense of the treatise, called the disputatio pro receptione in facultatem (“for the reception into the faculty”). After successful completion of the above, one was allowed to offer private classes at the university as a Privatdozent or lecturer.
The pro loco disputation is the defense of a Latin dissertation required upon occupying a particular professorship, either associate (ausserordentlich) or full (ordentlich), also commonly called an inaugural dissertation, and these are performed whenever a new position is assumed. The dissertation would need to be presented to the appropriate faculty, published by the university printer, and then defended publicly. If someone was immediately promoted to a professorship on their arrival at the university, they were supposed to participate in both a pro receptione and a pro loco disputation: the first for the right to teach, the second for the position itself.
Apart from the disputatio pro receptione et pro loco, there were also the public disputations that professors were expected to engage in on a regular basis, as stipulated in the university regulations, with penalties levied against slouchers. If one was a magister legens hoping to receive a professorship, then one needed to hold disputations to demonstrate one’s academic abilities. In 1710, the minimum number of disputations (“or other samples of erudition and skill”) in which one served as the principal was six to be considered for an associate professorship, and twelve for a full professorship. Goldbeck reports this was changed in 1749 to include the following criteria: (1) no one can give public lectures without first serving as the principal in at least one disputation (the habilitation or pro receptione disputation), (2) no one can be associate professor without having first held three disputations as a doctor or magister, and (3) no associate professor can be promoted to a full professorship without first giving three disputations as an associate professor. Although the standards were loosened here, Goldbeck notes that these criteria still led to a considerable number of disputations, especially in the years 1710-57, when there were over forty professors, and the number of disputations dwindled as their inconvenience became apparent. A schedule of forty to fifty disputations each year was highly disruptive for those students called on to participate as respondents, as well as for everyone else since classes were always cancelled on these days. It was further noted that one could well be an effective teacher without being effective in public disputations, and now, claims Goldbeck, one can become a professor without holding a single disputation, save for the pro receptione and pro loco [Goldbeck 1782, 38-9].
Public disputations offered an important public forum in the universities of the middle ages and early modern period, but as printed matter became more readily available, the importance of the Latin disputations lessened, so that by Kant’s day they had lost this original function of publicly presenting and discussing ideas, and became more a point of ceremony and one of the few remaining vestiges of Latin in the protestant universities. They were not without use, however. It was an honor for students to be asked to participate, and at times might take the place of a written testimony. Also, because the order of presentations mirrored one’s academic rank, with the subordinate speaking first, they offered a public show of the university hierarchy.
These disputations always involved a number of participants other than the principal himself, and it was the general duty of the teaching faculty to participate in them. Students also usually served in some capacity, typically with students participating in the morning and professor-respondents in the afternoon. The professors would choose whether or not to participate as a respondent, and the principal could not interfere with this. The disputations were conducted in Latin, and centered upon some Latin treatise prepared by the principal . A student assistant called a “pulsator” would ring a bell every half-hour to help participants keep track of time [Arnoldt 1746, i.207].
 The disputation might occur sometime after teaching had begun, however. A new pro loco disputation was not required of professors in the higher faculties moving from one chair to the next (e.g., from 2nd to 1st professor theology). But a new disputation was required of professors in the philosophy faculty who assumed a new chair for instance, the professor of practical philosophy assuming the chair of physics as well. This was a reasonable requirement since, as Arnoldt notes, “not every good poet ... is also a good Hebraist, mathematician, or historian” [1746, i.158-9].
 Daniel Arnoldt notes that, originally, each professor in the higher faculties had to hold a disputation every quarter year, and each professor in philosophy every three weeks [1746, 1.201-10]. This resulted in an unbearably high number of disputations, however, and eventually the numbers were lowered to one disputation per year for full professors in theology (failure to hold a disputation incurred a fine of two Joachimsthaler paid into the university treasury; in law, the fine was five gulden). Associate professors were required to hold two disputations each year. And in medicine, only the current dean was required to hold a disputation (or else pay a fine of one Joachimsthaler). The professors held their disputations in the Auditorium maximum, while the lecturers held theirs in the philosophy auditorium (this doubled as the student cafeteria, also called the Communität or Convictorium) [glossary]. In philosophy, the disputations were to occur on Saturday from 7-11 AM.
Kant engaged in three public disputations as the principal:
(1) a pro receptione disputation (i.e., habilitation), when he sought and received the privilege to lecture (the “Nova dilucidatio” essay, defended 27 September 1755) [writings]
(2) a general disputation performed as part of his unsuccessful application for an associate professorship of logic and metaphysics (Physical Monadology, defended on 10 April 1756) [writings] , and
(3) a pro loco disputation when he assumed the full professorship in logic and metaphysics (the so-called Inaugural Dissertation, defended on 21 August 1770) [writings].
We find Kant following here the criteria mentioned by Goldbeck, above, although making use of the proviso of “other samples of erudition and skill.” In Kant’s letter of application to King Friedrich II on April 8, 1756, he notes that he has already given two dissertations “of metaphysical content” and “soon after the coming Easter vacation will give the third”; he then asks for “the associate professorship of logic and metaphysics that was made vacant through the death of Professor Knutzen.” His first two dissertations were his magister essay (“De igne”) [writings], which did not involve a disputation, and his habilitation essay (“Nova dilucidatio”) which did. With the third essay (and second public disputation) he would complete the prerequisites for receiving an associate professorship. [more]
 Kant’s letter reads, in part [#5; AA 10:3]:
[…] Ich habe mich auch befließen dem allerhöchsten Befehle Ew: Königl: Maj: durch Ablegung zweyer öffentlichen dissertationen von metaphysischem Inhalte gemäß zu bezeigen, worauf bald nach zurückgelegtem Osterfeste die dritte erfolgen wird.
Die Begierde mich in einer von denen philosophischen Wißenschaften vorzüglich zu habilitiren, veranlaßet mich Ew: Königl. Majestät in tiefster Unterthänigkeit um die durch das Absterben des Seel. Prof. Knutzen erledigte außerordentliche Profeßion der logic und metaphysic auf der hiesigen academie anzuflehen. […]
The government requirement of a minimum number of disputations reflected a growing interest in the scholarly development of the professorate (and thus also the gradual shift away from viewing the university as merely a preserver and transmitter of known truths towards viewing the university as a research institution). Already in a report of 2 January 1737 we find J. J. Moser, the university director at Frankfurt, complaining that the majority of professors there write nothing and are invisible to the learned world. Likewise, a report on Halle of September 1, 1768, requests that professors there offer occasional evidence of their learnedness, and work harder at contributing to their disciplines. Finally, an edict from the Berlin consistory of 12 December 1768 requested all professors in the Prussian universities to publish “according to the style and taste of the day, with grace and beauty” [Bornhak 1900, 148].