On the horizon of this reflection is the question of identity and the self, dealt with through a writing of the body and intimacy that constitutes, along with the writing of death, the other side of the writing of life in the Essais. It is in the chapter entitled "Sur des vers de Virgile" (III, 5) that Montaigne goes furthest in writing about intimacy, in accordance with the imperative of coherence between saying and doing that leads him to announce: "I have ordered myself to dare to say everything I dare to do". This demand for uncensored freedom of speech thus justifies the presence of the body and its functions in the Essays, an essential milestone in the history of the privatization of the body and natural needs since the Renaissance.
In the chapter "De la coutusme et de ne changer aisement une loi reçue" (I, 23), Montaigne's careful examination of the act of blowing one's nose according to the customs of different peoples leads him to question the legitimacy of handkerchief use in the name of cultural relativism. Many of the details relating to the body and its functions in the Essais were censored in the 17th century. This is the case, for example, in the chapter "De laressemblance des enfans aux pères" (II, 37), with the reference to flatulence, and in the chapters "De l'expérience" (III, 13) and "De l'art de conférer" (III, 8), with the physical observations, admittedly introduced in a hygienic and medical context, but which bear witness to a preoccupation with the body deemed indecent.
In the chapter "De l'imagination" (I, 21), the example of flatulence challenges the idea of the will's control over bodily functions. The theme plays a crucial role in the definition of the self as intentio, voluntas ; it joins that of man's vanity, according to a series of recurring puns associating "top wind" and "bottom wind" through the phonetic proximity of the terms "vent", "ventre" and "vanité", further reinforced by the reference to the Latin etymons vanus and ventus : "We are everywhere wind" he writes in the chapter "De l'expérience", according to an image taken from Ecclesiastes. The chapter "Des coches" (III, 6) introduces a third kind of wind, the sneeze, deemed more "spiritual", more noble, than the other two.
The metaphor of defecation, very frequent in Montaigne's writing, whether comparing the Essays to the "excremens d'un vieil esprit" (III, 9) or, conversely, associating writing with food, refers to a topos dear to Rabelais, contrasting defecation and excremental literature on the one hand, and nutrition and well assimilated literature on the other. Montaigne's metaphors are not so much carnivalesque as they are frank, reflecting a desire to leave nothing "under wraps". The anecdote recounted in "L'apologie de Raimond Sebond" (II, 12) on the opposing attitudes of the school of Peripatetic philosophers and that of the Stoics on the subject of satisfying natural needs in public, be they flatulence or sexuality, according to the controversial example of Diogenes Laërce, whom Jean de Léry reported to have made love in public. The anecdote is an opportunity for Montaigne to demonstrate his disagreement with Saint Augustine on the thesis of the power of the will and the control of the mind over the body, against which he takes issue. The final, Epicurean lesson of the Essais, given at the close of Book III, bears witness to this: "Aesop, that great man, vid his maistre who pissed while walking: 'Quoy donq,' he said, 'nous faudra-t-il chier en courant?
