Pierre Rétat

1This is one of the articles with problematic boundaries because its territory at first appears uncertain. The articles “Descartes”, “Locke”, “Malebranche”, “Newton”, etc., are easily defined by the relations they establish between Montesquieu and the philosophers whose reference, memory or trace can be found in his works. But it is not certain that the whole of these relations forms a coherent network that allows us to reach a common point to which they relate; we must hope that the interpreter is not thereby condemned to vain research among floating, dispersed constellations.

2One could make another choice in this dictionary, and run through the articles “Condorcet”, “Destutt de Tracy”, “Durkheim”, “Helvétius”, etc., and look for Montesquieu’s philosophy by reflection among those who pretended to reveal it by commenting on it, condemning or exalting it. But from “Spinozism” to sociology raised to the master discipline of philosophy, to take only extreme terms, the spread is infinite, and the search is devoted to historical review of the interpretations. The returns to their object each time bring out some sparkle of truth, but the impossible sum of these sparkles will never create the object from which they are constantly extracted by the newness of perspective, and of which the mysterious and improbable unity would be called Montesquieu’s “thought” or “philosophy”.

3So we must take another path, and attempt to go back to the conceptual trunk of philosophy. What is given as such in Montesquieu’s works? What does the word, simply, signify, and what do the uses we find of it reveal to us of the comprehension of the subject? This comprehension is not necessarily our own, and one question among others cannot fail to arise: is philosophy as Montesquieu understands it that of the “Enlightenment” and to what degree can it be absorbed into it? This question is no longer the same as that of the interpretative returns just evoked, for it involves an immediate reading inseparable from the meaning that Montesquieu wanted to give to his enterprise, even it if forces it, and thus of the ambitions and values which he shared with his contemporaries.

4Everything must begin, everything does begin with metaphysics.

5This assertion would appear paradoxical only if Montesquieu’s condemnations of it were taken at face value: metaphysics “goes together with indolence: we study it everywhere, in bed, while walking, etc.”, “it only deals with big issues”, it “takes over all of nature, governs it at will, makes and undoes gods, gives and takes away intelligence, puts man in the situation of animals or removes him from it” (“s’accorde avec la paresse : on l’étudie partout, dans son lit, à la promenade, etc. […] elle ne traite que de grandes choses […] s’empare de toute la nature, la gouverne à son gré, fait et défait les dieux, donne et ôte l’intelligence, met l’homme dans la condition des bêtes ou l’en ôte”, Pensées, no. 202); in the books that deal with it “the infinite is everywhere encountered” (“l’infini se rencontre partout”, LP, [‣]); excessive heat easily explains the Indians’ doctrine of nirvana, “that metaphysical system” there appears natural (EL, XIV, 5). Yet it cannot be denied that Montesquieu gave himself to this indolent or intoxicating occupation of the mind, not even disdaining to go frequent an even more discredited relative of metaphysics, theology. Several fragments of the Pensées, which retranscribe youthful texts much later, prove this. Thus “Some reflections that can serve against M. Bayle’s paradox, that it is better to be an atheist than an idolater, with some other fragments and writings done in my youth, which I tore up” (“Quelques réflexions qui peuvent servir contre le paradoxe de M. Bayle, qu’il vaut mieux être athée qu’idolâtre, avec quelques autres fragments de quelques écrits faits dans ma jeunesse, que j’ai déchirés”): there Montesquieu posits, in a long, well-argued discourse, the bases of a belief in God based on the “new philosophy”, but circumscribed within narrow limits that leave its attributes outside the reach of human reason, according to a strict division between the capacities of the human mind and those of the heart, reason and faith (Pensées, no. 1946). Some “Notes on Cicero” recently discovered by Catherine Volpilhac-Auger (which will be published in t. XVII of the Œuvres complètes), will bring further testimony of the greatest interest on the readings he did and his philosophical culture in this period (roughly 1710-1715). It is certain , in any case that it paused for a rather long time on an interrogation about God, through Cicero, Bayle, Malebranche (whose notion of “infinity” he sharply criticized) and ended up, whatever the oscillations, with both a firm belief and a very limited intellectual grasp.

6Another of the Pensées, intitled “Doubts”, is more curious, in which Montesquieu, while affirming that he “does not pride himself on being a theologian”, lengthily discusses, with precise references to St. Paul, the question of predestination (no. 1945). It could be merely a sort of accident, if in the Persian Letters Usbek did not suddenly, incongruously, become a “metaphysician”, dealing very seriously with a very technical theological question, the contradiction between the foreknowledge attributed to God and his other attributes; he concludes with the question: “why so much philosophy”, since one is finally forced to humble oneself before an unknowable God?

7The “overflow” of his “philosophy”, for which Usbek apologizes, remains in truth moderate and is not followed up. But anyone who is not blind can see that there is a metaphysics of Montesquieu. We see it become again apparent in the Traité des devoirs (1725) and in the “Continuation of some thoughts that could not be used in the Traité des devoirs”, where, in an atmosphere of intense intimacy, he falls into a meditation on the necessity of God and on providence, against Hobbes and Spinoza (Pensées, no. 1266). We find it again at the beginning of the first book of L’Esprit des lois, which far from reducing to this “metaphysical residue” some have seen in it, on the contrary concentrates, in fearsomely and almost mysteriously abstract language, the authentic foundation of Montesquieu’s thought. He writes in Défense de l’Esprit des lois: “They will try to make us re-enter the schools of the dark ages. Descartes is quite useful for reassuring those who, with infinitely lesser genius than his, have just as good intentions as he: that great man was constantly accused of atheism” (“On voudra nous faire rentrer dans les écoles des siècles ténébreux. Descartes est bien propre à rassurer ceux qui, avec un génie infiniment moindre que le sien, ont d’aussi bonnes intentions que lui : ce grand homme fut sans cesse accusé d’athéisme”, OC, t. VII, p. 113). It is a liberated theology that Montesquieu, claiming Descartes’s example, opposes to his detractors buried in the shadows of the School: a brief theology, which delivers itself only in summary and in litotes, mixed with suspect stances, and which then could only provoke the condemnation of the Church, but could have been a true theology of the Enlightenment.

8Descartes wrote in Principles of Philosophy that “all philosophy is a tree the roots of which are metaphysics, the trunk is physics, and the branches that come from the trunk are all the other sciences, which come down to three principal ones: medicine, mechanics and morality” (“toute la philosophie est un arbre dont les racines sont la métaphysique, le tronc est la physique, et les branches qui sortent de ce tronc sont toutes les autres sciences, qui se réduisent à trois principales, à savoir la médecine, la mécanique et la morale”: “Letter from the author” by way of preface). We must long pause on this physics that imposes its presence between the roots and the branches. In the extremely broad sense of the time, it is the “science the object of which is the knowledge of natural things” (Dictionnaire de l’Académie, 1694), and as such it seems almost to conflate with philosophy or constitute its largest portion: “science that consists in knowing things by their causes and effects”; the philosopher is “he who applies himself to the study of the Sciences, and who seeks to know the effects by their causes and their principles” (ibid.). Montesquieu’s academic discourses and papers testify both to this common meaning of the words and to a capital moment in his own intellectual development. Founded in 1713, the Bordeaux Academy was composed of “philosophers”, in other words of “scientists” (savants) who worked toward the progress of the sciences, in the first rank of which is “physics” (la physique). It is in this perspective that Montesquieu positions himself to address his colleagues, to speak of their research, to designate their ideal of knowledge. The language of the 17th century, carried and transmitted by the learned institutions and journals that were created beginning in 1660, dominated the Republic of Letters in the first decades of the 18th. Montesquieu was a man of this broad in-between period, he participated in the academic movement that arose then, and himself founded in 1716 a prize in natural history alongside the physics prize founded in 1714. We must hear him, in the discourse given at the annual opening of the academy on 15 November 1717, reminding his colleagues of the severity of their engagements in the service of “philosophy”, which causes them to embrace “the most abstract sciences”, “that infinite that is everywhere encountered in physics and astronomy”, in mathematics, anatomy, chemistry, medicine, in other words all of philosophy and its object, nature, which is to be conquered by knowledge (OC, t. VIII, p. 109).

9Like his contemporaries, Montesquieu was conscious of belonging to a new age that marked the birth of genuine philosophy: “One could say that nature has done like those virgins who long preserved their most precious possession, and allow to be plucked from them in a moment that very treasure which they have so carefully preserved and defended with such constancy: after hiding for so many years, she suddenly showed herself in the last century; a moment very favorable to the scientists of the time, who saw what no one before them had seen! That century saw so many discoveries that it can be considered not only as the most flourishing, but also as the first age of philosophy, which in the preceding centuries was not even in its infancy: that is when those systems were brought to light, those principles developed, those fecund and general methods discovered; all of what we do now is based on those great philosophers” (OC, t. VIII, p. 111-112).

10Descartes was the great name of this new era. Evoking “the admirable discoveries of our times on dioptrics and catoptrics”, Montesquieu writes in Discours sur la cause de l’écho (1 May 1718): “But finally a philosopher came who, having studied nature in its simplicity, went farther than the others” (ibid., p. 154-155). With him began the saine physique that disavowed hypotheses drawn “from the sad debris of Antiquity” (Discours sur l’usage des glandes rénales, 1718, ibid., p. 167).

11This totally new age presents, through its very “revolutions”, nothing but unity and continuity in research and method. “All who reason” must take an interest in the “perfection” of “M. Descartes’s great system”, “that immortal system that will be admired in all ages and all revolutions of philosophy” (“ce système immortel qui sera admiré dans tous les âges et toutes les révolutions de la philosophie”), writes Montesquieu in his Essai d’observations sur l’histoire naturelle of 1719, where Newton, “that great philosopher”, is designated as “the successor to Descartes” (ibid., p. 213 and 223). Beyond all the oppositions, what counts for Montesquieu is to see nature writ large, to construct, on the basis of observation, a “system” that will stand the test of further observations, but must always surpass them: that movement where the experience of the “base artist” provokes the “great genius” who finally absorbs him, is the very one which we find again in Diderot’s De l’interprétation de la nature (1753; it should be remembered that all of Montesquieu’s academic papers were unknown until 1797). “Observations are the history of physics, and systems are their fable”: this quip in the Pensées (no. 163), which strongly resembles a commonplace, thus in no way reflects Montesquieu’s deeper thought. But at the same time, he was acting eminently as a philosopher in launching the Projet d’une histoire de la terre ancienne et moderne, when he proceeded to experiments on the respiration of frogs and ducks or on the production of mistletoe, when he recorded in Pensées so many notes on the most diverse natural phenomena, proposing “observations”, or yet when he froze a sheep’s tongue.

12Where philosophy is concerned, he was thus resolutely “modern”. The philosophy of the Greeks appears to him too little known, as that of all the peoples of Antiquity, for us to be able to judge them (Pensées, no. 291), but he makes nothing of their physics; he often denounces the verbiage of Plato and Aristotle, and considers in particular that their belief in objective qualities makes all of their philosophy outdated. He says so categorically in Essay on Taste: “The ancients had not well sorted this out; they considered as positive qualities all the relative qualities of our soul; for which reason these dialogues where Plato makes Socrates speak, these dialogues admired by the ancients, are today insupportable, because they are based on a false philosophy: for all this reasoning on the good, the beautiful, the perfect, the wise, the foolish, the hard, the soft, the dry, the wet, treated as positive things, no longer mean anything” (Encyclopédie, t. VII; [‣], 2020 ; OC, t. IX, p. 487); and he repeats it often in Pensées (nos. 211, 410, 799, 1154).

13So he is in no way disposed to seek in Antiquity forb warrants of a materialism that is in a sense natural to human thought, as do some of his contemporaries, erudite purveyors of clandestine manuscripts. He asserts wholly with restriction the total break between the “ancient” philosophy, nourished by infantile prejudices on the materiality of God and the soul, and the “new” one: “[…] before M. Descartes philosophy had no proofs of the immateriality of the soul” (“[…] avant M. Descartes la philosophie n’avait point de preuves de l’immatérialité de l’âme”, Pensées, no. 1946). The Cartesian break, with the radical distinction of extended substance and thinking substance, permitted conversion toward the subject the ignorance of which condemned all philosophy prior to Sophism. With the mechanistic postulate, it paved the way for an explanation of nature of which Usbek enthusiastically exalts the prodigious simplicity and fecundity: the “philosophers” follow “in silence the traces of human reason”, they explain “by simple mechanics the order of the divine architecture” they identify the general, unchanging, eternal laws that apply “to the immensity of space”, “the knowledge of five or six truths has filled their philosophy with miracles” (“la connaissance de cinq ou six vérités a rendu leur philosophie pleine de miracles”, LP, [‣]).

14Montesquieu could, on occasion, deplore the consequences of “this new philosophy that speaks to us only in general laws”, in pure understanding and clear ideas, and reduces everything to the “communication of motion”, to the loss of the sublime, of poetry, of “the spirit of glory and valor” (Pensées, nos. 112, 761, 810). He can show himself to be a very heterodox Cartesian by supposing that motion is inherent in matter (no. 76) or abstraction as resulting from the action of fibers on the brain (no. 1187). But what matters here is the concept itself of philosophy, the intellectual process and the gaze on the world which it presupposes, which henceforth in various forms inspires Montesquieu’s work and makes him conceive all at the same time a rationality of historical facts, a generalized legality of human facts, laws, institutions, mores, and a search for the causes that “affect the minds and characters”, in other words a physics of the soul (see the article devoted to Essay on the causes). “Account for…”, such is the central injunction. In this final movement, where the essential Montesquieu is to be found, the word that everything calls for is however wanting: if he sometimes calls himself a “political writer”, never does he call himself a philosopher. “Make me reflect and seem to feel. Make us learn without my teaching” (“Faites que je réfléchisse et que je paraisse sentir. Faites que l’on soit instruit et que je n’enseigne pas”), he asks of the Muses (EL, beginning of the “Invocation to the Muses»). To make reason speak, “the most exquisite of our senses”, the philosopher veils his face with a thin gauze, mixes his paths and repudiates his name.

15The same does not however apply to philosophy, which reappears in another mode. Montesquieu again expresses clearly, but in a very different spirit than that which animated the young academician, the consciousness of living in a new age of philosophy, and participating in its birth with his own work. The field of application of this new philosophy is the relations of men with each other and the rules that reason tries to impose on them. Thus the exercise of the right of conquest, the “law of peoples which we follow today”: “We must pay homage here to our modern times, to the present reason, to today’s religion, to our philosophy, to our mores” (“Il faut rendre ici hommage à nos temps modernes, à la raison présente, à la religion d’aujourd’hui, à notre philosophie, à nos mœurs”, EL, X, 3). Thus again the toleration preached to the Inquisitors in the “Most humble remonstrance”: “You are living in a century where natural enlightenment is brighter that it has ever been, where philosophy has illuminated the minds, where the morality of your Gospel has been better known […]” (“Vous vivez dans un siècle où la lumière naturelle est plus vive qu’elle n’a jamais été, où la philosophie a éclairé les esprits, où la morale de votre Évangile a été plus connue […]”, EL, XXV, 13). The “natural enlightenment” is ageless, but there are moments when man can rediscover it within himself, thanks to the advancement of “mores” and “knowledge”: “the knowledge which we have acquired in some countries, and which will be acquired in others, on the surest rules one can have in criminal judgments, interest humankind more than anything in the world”, and freedom is founded on “the practice of this knowledge” (“Les connaissances que l’on a acquises dans quelque pays et que l’on acquerra dans d’autres sur les règles les plus sûres que l’on puisse tenir dans les jugements criminels, intéressent le genre humain plus qu’aucune chose qu’il y ait au monde », et la liberté se fonde sur « la pratique de ces connaissances”, EL, XII, 2).

16Montesquieu entrusts jointly to the “philosopher” and to the “legislator” the mission of restoring to man the memory of his nature: “A given person could, at any time, forget himself; the philosophers have cautioned him with the laws of morality. Made to live in society, he could forget others; the legislators have restored him to his duties by the political and civil laws” (“Un tel être pouvait, à tous les instants, s’oublier lui-même ; les philosophes l’ont averti par les lois de la morale. Fait pour vivre dans la société, il y pouvait oublier les autres ; les législateurs l’ont rendu à ses devoirs par les lois politiques et civiles”, EL, I, 1). But this distinction is misleading or insufficient, for everything proves, and especially the preface of L’Esprit des lois, that, in a vanishing point toward which we should tend and sometimes approach, the two are indistinguishable. This vanishing point, both behind and before us, is “nature”. Philosophy is the secret motor that propels us towards it, through the diversity and relativity of laws and mores, it is the intimate urgency of enlightenment that would shine despite all obscurity.

17Similarly, “knowledge” and the struggle against “prejudices” obey in L’Esprit des lois the constant will to serve humanity: “It is by seeking to instruct men that one can practice the general virtue that includes the love of all” (“C’est en cherchant à instruire les hommes que l’on peut pratiquer cette vertu générale qui comprend l’amour de tous”, Preface). The act of reason thus conceived is a moral act: it posits the supreme value of a return of man to his essence. In this regard there is no way to understand Montesquieu without referring, beyond classical and Christian reasoning, beyond “natural law” and Malebranche, to the base of ancient philosophy and first of all to Stoicism. That is what gives it striking signification to the praise of the “Stoic sect”, placed as a tranquil philosophical provocation in the middle of book XXIV devoted to religion: at issue there is only “humankind”, the “happiness of men”, “duties of society”. Nothin is said there of philosophy, but everything designates the true face and the true mission of the philosopher.

18In the eyes of the first readers of L’Esprit des lois Montesquieu himself incarnated that ideal. Let us listen to Mme de Tencin: “Philosophy, reason, humanity have assembled to compose this work” (2 December 1748, Masson, t. III, p. 1148); the chevalier d’Aydie: “it is, they say, the work of the good citizen, a statesman, a fine wit and a philosopher” (8 February 1749, ibid., p. 1177). A work that “does honor to humanity”, “benevolence for humankind”, “truths useful to humankind”…: the insistent alliance of philosophy and humanity defines the turn where the Enlightenment is born, where philosophy accedes to a status of encompassing generality, achieves the synthesis of all the values and implicitly fills the function of the end of history.

19So we are not surprised that D’Alembert should accord to Montesquieu a general benediction in the “Eulogy” which he published in 1755 at the beginning of volume V of the Encyclopédie, and which was for a long time to begin the editions of his works. “A rising genius”, he prepared L’Esprit des lois the way Newton meditated from afar over his discoveries; from his youth he cultivated the study of jurisprudence “as a philosopher”; his Romains could be intitled “Roman history for statesmen and philosophers”; even in The Temple of Gnidus Montesquieu-Anacreon is “still an observer and philosopher”; and besides that “the man of all countries and all nations”, “benefactor of humanity”, inspired by “the spirit of the citizen” and “love of the public good”. One idea with a great future again appears in D’Alembert: Montesquieu does not insist on “metaphysical discussions relative to man imagined in a state of abstraction”: he managed to dismiss a part of the worn out, repellent philosophy.

20We easily see what in Montesquieu’s work justifies this ideological reduction and also what makes it unbearable. Its resurgence in a context of sociological or Marxist interpretation proves that it found its origin in a deep and constitutive trait of the work, despite all the oppositions made to it. Let us be content with touching here on an apparently simpler question: how to situate Montesquieu in “Philosophy”? Several texts from L’Esprit des lois cited above place together, among the causes of the progress of humanity, philosophy and religion. This detail alone signals a deep dissonance. The relationship of Montesquieu to religion offers one of the most revealing indices of the hard-to-assign position occupied between the rationalism of the 17th century and that of the Enlightenment, between the various currents of unbelief and a deism that is sometimes close to an enlightened Christianity.


Prolem sine matre creatam. But this miracle must be hidden from the dictionary’s readers, who would be incredulous.