In his introductory remarks to this annual seminar (on 28 October 1986), Deleuze stated that he would have liked to devote this seminar to the theme "What is philosophy?”, but that he “[didn’t] dare take it on” since “it’s such a sacred subject”. However, the seminar that he was undertaking on Leibniz and the Baroque instead “is nearly an introduction to ‘What is philosophy?’” Thus, the 1986-87 seminar has this dual reading, all the more significant in that, unknown to those listening to Deleuze (and perhaps to Deleuze himself), this would be the final seminar of his teaching career.
Deleuze planned the seminar in two segments: under the title “Leibniz as Baroque Philosopher,” he presented the initial operating concepts on Leibniz, notably on the fold. Circumstances during fall 1986 limited this segment to four sessions with an unexpected final session in the first meeting of 1987 (6 January). For the second segment, Deleuze chose the global title “Principles and Freedom”, a segment consisting of fifteen sessions lasting to the final one on 2 June.
The transcriptions into French and corresponding translations into English were made possible through access to transcripts initially available from Web Deleuze (created by Richard Pinhas) and through access to the recordings available from the Bibliothèque Nationale de France (BNF), faithfully produced over a decade by one participant in Deleuze’s seminars, Hidenobu Suzuki. According to François Dosse in Gilles Deleuze, Félix Guattari: Intersecting Lives (Columbia University Press, 2011), Suzuki “becomes an institution all to himself”, to whom Deleuze would refer colleagues if they weren’t able to attend one of the sessions.
The following sessions' translations and transcriptions are original to this site; all others are developed and augmented based on the recordings available at the BNF thanks to Hidenobu Suzuki: sessions 1 (Oct 28, 1986), 2 (Nov 4, 1986), 3 (Nov 18, 1986), 5 (Jan 6, 1987), 6 (Jan 13, 1987), 9 (Feb 3, 1987), 11 (Mar 3, 1987), 15 (Apr 24, 1987), 16 (May 5, 1987), and 20 (2 June 1987).
On 17 March 1987, in the midst of this seminar, Deleuze travelled to the Fondation Bordeaux Université to present his talk "Qu'est-ce que l'acte de création" ("What is the Creative Act"), which can be viewed here (and with English subtitles, here).