Asked to characterize Cartesian discovery, one might immediately turn to Descartes’s works on mechanics, optics, mathematics, or even metaphysics. In each of these cases, the object of discovery would be something actual, something that, theoretically at least, obtained in Descartes’s early-modern world. While the Cartesian mind and body might challenge how we use the word "actual," depending on our readings, Descartes is nevertheless always writing about how actual human entities work. Except for when he’s not. Le Monde, or The World, which became available only posthumously, differs from much of Descartes’s other work in that it uses a self-consciously imaginative narrative for philosophical inquiry.1 While this experiment in creative writing subsequently shaped its author’s use of the "fable" in the Discourse on Method, The World is the only one of Descartes’s texts to be structured by the logic of a literary possible-worlds narrative. It is the text that demonstrates most clearly Descartes’s production of a kind of knowledge that we might call poetic.
Descartes’s mechanist "paper-world" has a moon, a sun, and is surrounded by other planets and stars; its seas ebb and flow; its light refracts; it is inhabited by men that have souls, bodies, desires, and drives.2 Rather than describing discoveries about the actual world, this text offers insight into a possible world, one where nature operates like a machine, obviating the need for God’s creation of man, animals, and so on. In explicitly engaging with a possible world, The World is different from early-modern mimetic literary texts that reproduce, in one form or another, the actual world. Further, unlike utopian reconstructions of the real, such as Thomas More’s Utopia or Francis Bacon’s New Atlantis, The World emphasizes novel creation alongside the unique discovery enabled by reading imaginative texts.3
While Descartes had precedents for his possible world (Lucian of Samosata wrote a True History of a possible world in the moon in the second century A.D.), The World is among the earliest examples of explicit possible-world literary creation for epistemological purposes. Consequently, it offers a surprising perspective on what "discovery" entailed for the early-modern. While seventeenth-century Europeans were enchanted by empirical and ocular demonstration, The World attests to the power of imaginative stipulation for discovery, and to the ways in which discovery occurs in and through language. Cartesian mechanism is a textual event first, one that is actively called into being by the text. While the text refers to a "non-existent" possible world, it nevertheless retains the epistemological status of the "real." Only later, through processes of analogy and comparative analysis, does the object of readerly and writerly discovery return to the actual world.
Descartes recognized that his new mechanist universe was dangerous in the intellectual climate of the 1630s, and he chose to suppress the text rather than have it and himself subject to the scrutiny of the Catholic Church.4 While he published some of the mechanical arguments from The World and made reference to the text often in other publications such as the Discourse (1637) and the Principles of Philosophy (1644), the complete text of The World is lost to us. What we do have are portions of the text posthumously published by Claude Clerselier as The World, or the Treatise on Light, and the Treatise on Man (1664). The Clerselier World is fragmented. The two treatises suggest that intervening text may have existed or was planned (the Treatise on Man opens by referring to text which is not extant), and they suggest that a third treatise on the soul was planned, though it is unclear if this text was ever written.5 Nevertheless, the Treatise on Light and the Treatise on Man preserve the structure and much of the content of a remarkable text that is simultaneously Cartesian natural philosophy and, in modern generic terms, a "possible-worlds fiction."6
To date, literary theorists have used possible-worlds theory as a way to develop theories of fictionality.7 But for Descartes, to say something was "fictitious" was to disparage its intellectual value and epistemological rigor; consequently this essay only glances at the issue of "fiction." Instead, possible-worlds theory helps us to discriminate between writing that operates in a conditional or propositional vein and the traditional early-modern mimetic modes of writing. Insofar as The World demonstrates that early-modern "discovery" could happen between the covers of a topic—that discovery need not be predicated on the real, but could occur through simultaneously aesthetic and pragmatic channels—it has a great deal to offer modern theory.
Poetic Knowledge
Matthew Jones observes that Descartes held a theory of poetic knowledge, strongly influenced by Jesuit training in rhetoric.8 However, neither classical rhetoric nor the Jesuit appropriation of it included the creation of possible worlds in the arts of persuasion. Instead, rhetoric remained largely mimetic in one form or another. Consequently, Jones’s excellent work on Descartes’s uses of his rhetorical training can be extended if we recognize Descartes’s innovations, vis-a-vis that training, as well. Descartes utilized possible scenarios and possible worlds to enable the kind of enargia, or vivid lively description, valued by Jesuit rhetoricians and central to knowledge according to Descartes. The constraints of creating a coherent possible world required that Descartes simplify the extremely complex issue of creation (down to the principle of motion), allowing clear articulation of the linkages between elements. Insofar as he was able (in his own estimation) to make those linkages and the primary elements of his new world as clear as other kinds of intuitions, Descartes felt that he was able to offer a fable as epistemologically valuable as any observation or representation of the "real" world. Where traditional rhetoric used language to represent the world mimetically, Descartes extended that tradition by including new worlds, thereby putting the fable to rigorous philosophical work.
Cartesian poetic knowledge is characterized by knowledge of "unifying causal structures," and it is in order to present such unifying structures—despite the logical contradictions and theological implications that such structures would have for the actual world—that Descartes turns to the literary production of possible worlds.9 While relatively little critical attention has been paid to Descartes’s use of poetic modes, an interest in the use of poetic language for philosophical inquiry is evident in his early work. In his notebooks he observes:
It may seem surprising to find weighty judgments in the writings of the poets rather than the philosophers. The reason is that the poets were driven to write by enthusiasm and the force of imagination. We have within us the sparks of knowledge, as in a flint: philosophers extract them through reason, but poets force them out through the sharp blows of the imagination, so that they may shine more brightly.10
Poets alone utilize a creative force that, upon impact with the intellect, produces intuitions so bright that they compel belief in their certainty. Thus poetic writing offers superior access to knowledge. Imagination is a critical tool for Cartesian knowledge; in the Rules for the Direction of the Mind (1628), Descartes suggests that in order for the intellect to perceive truth it must "be assisted by the imagination."11 The "sparks of knowledge" shine in the hands of poets, whereas philosophical "extraction" offers the reader something considerably more dull.
Mimeticism and Possible Worlds
It is important to make a clear distinction between mimetic and possible literary worlds. Possible worlds differ from other literary productions by rejecting a mode of signification that depends on reference to an actual world. While possible-world theory has become increasingly popular for modern philosophers and literary critics flummoxed by fictional and impossible language, the issue of the nature of literary signification was endemic to early-modern Europe. Sixteenth- and seventeenth-century mimetic theories generally operated along either the Aristotelian or Platonic axis. For Aristotle, language faithfully simulates phenomena, and is firmly grounded in experience of the "actual." The poet’s or dramatist’s function is to "express the universal," imitating not just what has happened, but the "sort of thing that a certain kind of person will say or do probably or necessarily."12 In order for poetic writing or speech to be probable, according to Aristotle, the poet imitates actions permissible within the bounds of "real" nature, consequently preserving a strong connection between representation and an "actual," if generalized, referent. (The connection itself remains a matter of convention.) This is part of Aristotle’s famous limit on poetry; what could be discovered was restricted to the domain of human interaction.
In contrast, sixteenth-century Neoplatonic theories generally held that words were intrinsically mimetic, revealing something significant, essential even, about their referents, regardless of that referent’s status as thing or action.13 Art "reach[es] beyond natural phenomena to the underlying principles of nature," revealing the ideal order behind representations.14 If language is inherently reflective of what it expresses, then literary production, for the Neoplatonist, is a locus for discovery of the hidden order of the universe. Yet the Neoplatonic text, like the Aristotelian, remains basically mimetic—or "world-imaging," as Czech literary theorist Lubomir Dolezel phrases it. Such world-imaging texts give the reader access to the actual world via what we now might call the virtual or representational medium of the text.15
By contrast, the writer of possible worlds remains entirely within the virtual. S/ he posits a world that is an alternative to the actual world, in its order and origins. As Ruth Ronen suggests, possible worlds texts do not make meaning "relative to an extratextual universe."16 Instead, we see within any possible world "discourse constructing its own world of referents."17 The imaginary objects to which the propositional discourse of poetic writing refers do not carry a fixed ontological status: they exist neither in physical-material reality, nor in a kind of mental existence. Instead "they remain inherently indeterminate; their state of being is confined to what meaning-units of the text reveal."18 The indeterminacy of the possible in no way thwarts Descartes’s sense of its epistemological value; he is particularly fond of asserting that possible entities are "real," even if they are not "something actually and specifically existing."19
The nature of the relationship between the closed system of meaning of possible worlds and other, more open, models of reference in fictional worlds, especially utopias, is a topic of debate amongst modern scholars. According to Mary Baine Campbell, for example, utopian worlds are "not really a version of an other world" because the "normative example" of the utopian world "exert[s] a pressure on readers to alter their own worlds in its direction."20 By contrast, Marie-Laure Ryan subsumes both possible worlds and "wish-worlds," which include utopias, under the general rubric of "relative worlds"—all of which are relative to some actual world.21 Campbell’s formulation rests on a particular relationship between reader, fictional world, and actual world; put crudely, the text directs the reader to change the world. I suggest reframing our definitions in terms of construction, rather than reception, a move that is more in line with Ryan’s work. In texts like More’s Utopia (1516), or Bacon’s New Atlantis (1627), the authors pull from society "the rules it has prescribed itself in different circumstances, select what appears to them the wisest, and linking them together in an imaginary vinculum, give birth to a state, a form of government, a code of laws, and a system of manners, such as in their totality never existed"—an Aristotelian form of mimesis.22 In contrast, The World, according to Descartes, is not abstracted from the actual in order to produce the ideal; rather, it produces an alternative possible world from which lessons in mechanics, metaphysics, and optics can be learned.
While possible worlds are created as alternatives to the actual, this is not to say that possible worlds are not accessible (in a logical sense) to the actual. Indeed, the epistemological power of The World depends on such accessibility. Ryan argues that such self-enclosed narratives retain a radical otherness to the actual while maintaining an "epistemic or model function."23 Descartes spatially produces Ryan’s "radical otherness" for The World, while simultaneously calling attention to its crafted or closed nature. The reader is exhorted to "allow your thought to wander beyond this world to view another, wholly new, world."24 This wandering takes the reader "far enough to lose sight" of the actual world, suggesting a space not only other, but so distant as to prohibit proximate comparison. The crafted nature of this other world is signaled by Descartes’s rhetoric of invention and creation; the new world is "called forth" by Descartes into an imaginary space "invented" by philosophers.25 Together, reader and author spend pages inventing, imagining, and conceiving of a different (alternate, in Ryan’s terms) possible world. While this world is "a most perfect world," Descartes continues to keep it discrete in terms of both creation and reference, leaving it to others to "explain the things that are in fact in the actual world."26 While in the case of The World a comparative return to the actual is the final goal—Descartes wants to demonstrate that an alternative, mechanically created world could look just like our own—the comparison is always between two distinct worlds.
Discovery in The World
Words can write worlds into being. Yet in The World it is God’s ability, in principle, to bring a given "paper world" into material being that gives such a world—a text—its epistemological value. Discovery, in this scenario, is not of what is, but of what may be: a possibility of God’s creative capacity to match the creative writing of man. Descartes is clear that his possible world does not challenge received histories of creation. Neither The World, nor its "real" but non-existent referent, can be collapsed onto the actual world. The "fable" does "not … explain the things that are in fact in the actual world."27 Instead, it allows Descartes to "make up … a world in which there is nothing that the dullest minds cannot conceive;" a world as clear and distinct as intuition.28 While creation may not have happened in "the old world" (i.e. the actual world) as it does in Descartes’s possible world, nevertheless, according to Descartes, this world is possible: "since everything … here can be imagined distinctly" and "it is certain that God can create everything we imagine."29
According to modern theories of possible worlds, writing the possible entails creation in thought and language: stipulation rather than discovery. The veracity of such writing is subject only to systems or regulations imposed by the writer and reader.30 In The World, the regulations are Cartesian intuitions. While these intuitions constitute a kind of discovery in Cartesian philosophy ("intuitions" are for Descartes truths subject to discovery) The World is a text that stipulates in order to discover. From intuition Descartes "make[s] up" a world.31 The active, creative force of "makes up" signals stipulation, which is then further refined and reinforced when Descartes suggests that even if God has not created a world as it is represented here, it is enough that he could. As a devout Catholic, Descartes was not in a position to argue that he was the actual author of a possible world. Instead, he wrote an account of what is possible for God to make. The reader and Descartes "suppose that God creates anew so much matter all around us," not that they do so.32 While the reader and author together "imagine" and "conceive of" this world "as [they] fancy," it is nevertheless God who establishes its laws, divides its matter into parts, and sets the universe in motion.33 While Descartes has "imagined" and made up this world "as [he] pleased," its certainty, and therefore its intellectual utility, is based in God’s creative power; even if he has not made this world already, "he can create everything we imagine."34 As Descartes says, what is "true or possible" is such only because "God knows [it] to be true or possible."35 Consequently, rather than operating according to the modern sense of creative "stipulation," The World is a stipulation of divine creation, and therefore an object of discovery.
This imaginative stipulation is cast in the same terms used throughout Descartes’s corpus to describe his method of "discovery." It is just as certain as empirical or observational discovery: everything in this divinely-created new universe can be known through the narrative "so perfectly" that his readers cannot even "pretend to be ignorant of it."36 What the reader cannot be "ignorant of’ is the possibility of a different divine creation than the one attested to by and for the Earth. The narrative offers knowledge of divine capacity, not necessarily material reality. Interestingly enough, it is only through a careful and precise process of imagination that this discovery of divine creative capacity is possible. Imagination is necessary because the possible world is not written from within the context of the material world.
The Possible World as Intuited
Possible worlds are unified and coherent, and this feature was important to Descartes’s own sense of The World’s epistemological value. His theory of intuitions often requires that the investigator reduce the question at hand to the most basic level in order to achieve ideas that are clear and distinct. Nonetheless, Descartes also allows that more complicated ideas may be compound intuitions, which are just as valid as the simples from which they are constructed.
A 1648 exchange recorded by Dutch scholar Frans Burman illuminates how compound intuitions authorize possible entities. Frustrated at Descartes’s insistence that "imaginary" mathematical entities like polygons were "real," even if not present in natural creation, Burman challenged Descartes with the example of the chimera. For Burman, a poetic figure like the chimera—described in Homer’s Iliad as a horrible hybrid animal, "lion-fronted and snake behind [and] a goat in the middle"—could be neither real, nor epistemologically useful.37 On the contrary, Descartes retorted: "everything in a chimera that can be clearly and distinctly perceived is a true entity."38 Consequently, it was possible for the compound of those clear and distinct parts likewise to have a "real and true nature."39
For Descartes, clear perception enabled by the motion of the imagination could qualify the chimera as "something which does not actually exist in space but is capable of so doing."40 This was different from "clearly imagining" the chimera: "even though we can with the utmost clarity imagine the head of a lion joined to the body of a goat," Descartes tells Burman, "it does not therefore follow that they exist, since we do not clearly perceive the link, so to speak, which joins the parts together."41 Imagination aids the intellect toward clear perception of not just the featured elements, but also the nature of their juncture. It was not enough to imagine that a lion’s head and goat’s body could go together; one had to be able to understand how they went together as well.
In emphasizing linkages we can see Descartes’s prioritization of a "simultaneous cognition" of knowledge. He is looking for the unifying principle that constitutes poetic knowledge rather than individual truths in succession.42 When dealing with multiple connected ideas, as in the case of the chimera or of a possible world, there must be what Descartes describes in the Rules as a "continuous movement of thought," enabled by the imagination, in order to unify the separate parts of a more complicated intuition.43 The regulating order of the Cartesian possible world must remain unified, coherent, and everywhere apparent; the linkages of the Cartesian imagination "must nowhere be interrupted," lest the entire narrative be "immediately broken" and its certainty collapse.44 Not that the imagination’s aid is always salutary; the imagination may put "things together poorly" and, in so doing, "makes us imagine many events are possible when they are not."45 Thus the chimera would be a fiction if the links between goat and lion were not present. But when the links are made clearly, such that interconnections are as clear and distinct as the ideas, then poetic knowledge is a kind of all-at-once cognition of both the nature of the unifying principle(s) and an appreciation for the beauty of the system.46 While fictions fail (epistemologically) because of poor construction, coherent possible worlds successfully enable discovery.
The World with its mechanistic "links" may be only possible, and, therefore, imaginary, but for Descartes, it is not "fictitious."47 Indeed, Descartes’s concern to preserve the conceptual unity and validity of The World prompted him to suppress the text, despite his obvious affection for its argument. In April 1634 Descartes wrote to the Minim mathematician Martin Mersenne, apologizing for his delay in sending a long-promised copy of The World. Citing the prosecution of Galileo for heresy for his 1632 Dialogue Concerning the Two Chief World Systems, which included a heliocentric hypothesis, Descartes informed Mersenne that he refused to release his text. The crucial point for Descartes was the need to preserve the unity of the narrative of The World: "all of the things I explained in my treatise, which include the doctrine of the movement of the earth, were so interdependent that it is enough to discover one of them false to know that all the arguments I was using are unsound."48 With the prosecution of Galileo, it seemed certain to Descartes that the heliocentrism of his possible universe would likewise come under attack and that such an attack would undermine the entire text. The issue was not heliocentrism, per se, but Descartes’s belief that a single false link would render the epistemological value of his world null. If heliocentrism were refuted, Descartes’s possible world would cease to be coherent and unified, and the text would become a mere fiction.49 He had designed his mechanistic "fable" to produce the simultaneous imaginative motions that would enable his readers to intuit, and therefore to know, the possibility of mechanistic creation.50 Afraid that a challenge from the Church would disrupt his delicate, interconnected narrative, Descartes chose not to publish the text.51
Cartesian Possibility and Aesthetics
Possible worlds, suggests Thomas Martin, are particularly satisfying objects of knowledge, because they are "eminently more knowable than our own enigmatic lives."52 They enable the complete knowledge that eludes encapsulation in the actual world. To Descartes, The World’s poetic knowledge was so clear that it would allow "even the dullest minds" to grasp the possibility of mechanist creation.53 This knowledge functioned at two levels. First, the textual model demonstrated its own possibility. Prior to reading The World, the reader might have "taken [Cartesian light mechanisms] to be very paradoxical," but after reading they become "clear" and visible.54 Similarly, readers initially may have had "doubts" about the mechanisms of mortal bodies; but after reading, "they will not be able to imagine anything more likely" than Descartes’s model.55 Second, Descartes designed the text to teach the reader to pick out analogous mechanistic principles at work in the real world. By offering a simplified model, the text teaches the reader to cut through the noise of the complicated real world, in order to discover mechanist principles at work. Discovery is a two-stage process, then, that begins in the text and continues in the world. The clarity of that perspective in the possible world is what lends authority to a translated perspective in the actual world. In some ways this is utterly conventional. Learning how to read the natural world through a text was extremely common. What is different here is the level of certainty attributed to textual evidence and the elision of the actual world as the authorizing reference for the text. There is no recourse to empirical proof here—because Descartes’s mechanistic world is only possible, the text alone must be evidence enough. The turn to the actual world does not verify the text; rather, it deploys the knowledge gained therein in a comparative exercise. While not an outright rejection of empirical proof, Descartes’s world is an alternative approach to discovery that places imaginative narrative—the aesthetics of which was itself evidence of the epistemological value of the story—at its center.
It is worth noting that this text is notable not only for its location in the history of poesis and possible worlds, but also because it provokes a rethinking of certain generic distinctions within possible-worlds theory itself. For Dolezel, the possible worlds of fiction are aesthetic artifacts. Those of natural science are practical, non-aestheticized models of alternative worlds. Descartes, however, values his possible world in both aesthetic and pragmatic terms. As we will see, his possible world is simultaneously fiction and natural science (in Dolezel’s formulation). As such, it is yet another reminder to us that "discovery," at least in the early-modern period, can be as much about aesthetics as it is about knowledge. In troubling the distinction between "stipulation" and "discovery," which is at the heart of modern possible-worlds theory, The World also illuminates a historical moment in which the line between creative agency in the author, and discovery of a divinely created possibility, is blurred. Descartes cannot claim that the written word actually creates new material worlds. He can and does claim, however, that texts can articulate what has not yet been created; that, in addition to their ability to describe the world, they can explore the contours of divine possibility.
In building a radically other world, Descartes simplifies the natural order of his universe by rejecting the paradigm of Aristotelian qualities and the traditional four elements and substituting for them a tri-elemental universe devoid of all characteristics, except those of motion and extension. While complex ideas, such as possible worlds, can qualify as intuitions if the linkages are clear, Descartes strongly privileges focusing on "minute details" first.56 Accordingly, The World’s first five topics focus on topics of a far smaller scale than world-creation, thereby serving both a methodological and narratological function. In the Rules, Descartes argues that we should not begin … by investigating difficult matters. Before tackling any specific problems we ought first to make a random selection of truths which happen to be at hand, and ought then to see whether we can deduce some other truths from them step by step, and from these still others, and so on in logical sequence. This done, we should reflect attentively on the truths we have discovered and carefully consider why it was we were able to discover some of these truths sooner and more easily than others, and what these truths are. This will enable us to judge, when tackling specific problems, what points we may usefully concentrate on discovering first.57
What Timothy Reiss has called Descartes’s "aesthetic rationalism" is apparent here.58 Inquiry begins with a deductive sequence and ends in a synthesis that enables, through the ability to "judge," further discovery. By reflecting on the knowledge obtained from a purportedly random selection of "truths," Descartes and his reader can recognize the interconnections that enable the discovery of order ("why it was we were able …"). Recognition of interconnection enables judgment, making further discovery an aesthetic (based in judgment) rational process. What Descartes describes in the Rules as "sound judgment" enables those of sufficient intellectual capacity to make new discoveries. And for the general public, it also makes possible an aesthetic assessment of the sciences as a whole: "even those who, through lack of intelligence, cannot make discoveries by employing first principles will still be able to recognize the true worth of the sciences, and this will enable them to arrive at a correct judgment of the value of things."59
Descartes opens The World with possibility: "I want to draw to your attention that it is possible for there to be a difference" between the sensation of light and the cause of that sensation. Built into Descartes’s suggestion is his familiar skepticism about the senses. But here it is cast in terms of an alternate possible state of affairs: when looking at light what we think we see is not the cause of our perception of light. Descartes offers two analogies to illuminate the interpretive nature of the error, the first of which will suffice here. As with conventional language, Descartes argues, it is possible that the idea of light is no more connected to the sign of light than the mechanics of speaking are connected to the content conveyed by speech. Descartes asks: now if words, which signify something only through human convention, are sufficient to make us think of things to which they bear no resemblance, why could not Nature also have established some sign which would make us have a sensation of light, even if the sign had in it nothing that resembled this?60
Descartes suggests that light is nature’s conventional sign for motion. The error is in the relationship of sign to signified; Descartes argues that this relationship is conventional rather than necessary or one of identity. Interpretation becomes the central issue, and the possibility of possibility is the occasion to reconsider the nature of interpretation. Descartes argues that it is possible that the natural world is a system of signs subject both to convention (hence, arbitrary signification) and to misinterpretation. In Descartes’s possible world, the topic of nature has to be read with as much interpretive effort as any other conventional-language text. At this early stage in the text, Descartes is only proposing possible scenarios in the real world, not entire new worlds. Nevertheless, this introduction owes as much to the logic of possibility, and its epistemic value, as it owes to Cartesian theories of light. By reforming light into a conventional sign, Descartes asks his readers not to be convinced "absolutely that light is something different in objects from what it is in our eyes"; he wants "only to raise a doubt about it for [us], to prevent [our] being biased in favor of the contrary view, so that we can examine what light is."61 It is under the condition of possibility that Descartes posits further collaborative inquiry.62
The reader is thus introduced to possibility as the enabling condition of knowledge. It is only once we, as readers, accept the possibility that light is not what we think it is that real discovery begins. This is fundamentally different from reading this possibility within a tradition of probabilistic rhetoric that allowed early-modern writers to skirt charges of heresy or to massage the non-syllogistic rigor of their propositions. While the possible scenarios proposed in the first five topics may be usefully read in the context of probability, the larger "fable" that Descartes introduces at the end of topic Five does not fit easily into this paradigm, nor does the context of early-modern probability adequately account for the non-mimetic mode Descartes uses to articulate his possible world.
The selection of topics that begin The World, including light and the nature of motion, cannot reasonably be considered "random"; Descartes rarely begins with anything that could be considered truly random. Instead, he often begins with what appear to be arbitrary selections that, in the end, serve the goal of each proof precisely, as he does with the first five topics of The World. Topics One and Four introduce possibility as a condition for inquiry, and the five "introductory" topics model the methodology laid out by Descartes in The Rules. At the same time, they establish the fundamental elements at the heart of the possible world, thereby establishing the certainty and aesthetic value of the alternative principles essential to the coherence of Descartes’s narrative.
Descartes eliminates all "superfluous" data in order to arrive at the simple principles upon which his alternative world will be built.63 topic One establishes possibility as a condition for inquiry and disabuses readers of the bias that the sensation of light is connected necessarily to the cause of that sensation. Topic Two continues the discussion of light by defining the nature of light in fire or stars in terms of motion. Topic Three presents a theory of the conservation of total universal motion in the course of a discussion of "hardness" and "fluidity." This, in turn, places all bodies along a fluid-solid state spectrum defined in terms of motion. We begin to see, at this point, the nature of the interconnection of the "random" selection of light, fire, "hardness," and "fluidity": Descartes understands them all in terms of motion. Topic Four seems to shift focus somewhat, opening with a question of perception related to that in the first topic and reintroducing the problem of bias that was at issue in that topic as well. "But we need to examine in greater detail," Descartes tells us, "why, although it is as much a body as any other, air cannot be sensed as easily."64 In the ensuing discussion, Descartes argues that the universe is a plenum (vacuums do not exist), and planetary and other celestial bodies float in a rarified fluid that we cannot see because we are surrounded by it. Though initially about perception, this topic argues that motion must be circulatory (all bodies must be in motion in the same direction in order to open the space into which any given body will move if there is no vacuum or empty space). Descartes, at this point, has defined light in terms of motion, determined that all bodies exist along a solid-fluid spectrum defined in terms of motion, and established the kind of motion possible given that the universe is a plenum—the "links" that will make this story intellectually and imaginatively clear are "made" of motion. What remains is to define the elemental components that will move in this universe.
This is the project of topic Five, in which Descartes reduces the traditional four elements (fire, water, earth, air) to three (fire, earth, air). He defines each in terms of motion and extension (shape and size), thus continuing the mechanical emphasis of topics One through Four. This move also disposes of the Aristotelian qualities of hot, cold, wet, and dry that traditionally accompanied the four elemental natures and, in Descartes’s opinion, cluttered philosophical inquiry. Descartes then arranges the three elements in a mechanical hierarchy. "Fire" is composed of tiny entities with great speed and "no determinate size, shape or position" (they fill in the space between larger bodies, ensuring that the universe is a plenum).65 "Air" is of "middling" motion and size, with a spherical shape, and "earth" is "so large and closely joined … that [its particles] can resist the force of motion in other bodies."66 Descartes distinguishes elemental air, fire, and earth from the "gross air [that] we breathe or the earth on which we walk."67 With this last topic Descartes closes the introductory material of The World, thus completing the "ordering and arranging of the objects on which we must concentrate."68
In reducing the complicated problem of the construction of the universe to the motion and extension of three clearly defined elements, Descartes has employed possibility as a device to overcome anticipated biases (that what we perceive as light is the same in the bodies in which we perceive it, and that where we see nothing, nothing is present). But it is not enough simply to have found motion in the actual world; Descartes’s objective is to demonstrate that God could have used these principles of motion to create out of "chaos."69 And to demonstrate that even "if everything our senses ever experienced in the actual world seemed manifestly contrary" to this mechanistic method of creation, the certainty of these principles "in the new world" is so "infallible" and "perfect" that the reader must acknowledge that such creation is possible.70 This introductory material, then, models the Cartesian method and articulates the principles of inclusion and exclusion that govern the narrative. This clear, distinct, closed, and completely coherent narrative enables a new poetic world to emerge.
The "End" of the Possible World: Analogy
Writing about this new possible world served two functions for Descartes. First, it allowed him to put forth a model of a world constructed "without forms or qualities," one based solely on a modified fluid mechanics.71 It is an "alternative design of the universe constructed by varying the basic physical constants"— constants such as basic elements, the nature of light, and so on.72 While the cohesive narrative qualified the possible world as certain as intuition, another part of its value lay in the ability to argue by analogy for similar mechanisms in the actual world. Descartes’s possible new world is one "in which one will be able to see not only light, but all other things as well … that appear in the actual world."73 Understanding the possible world allowed the reader to perceive correctly phenomena in both worlds. By eliminating the multitude of other considerations and stripping down to a model of creation based solely on motion, Descartes sought to enable his readers to conceive "distinctly" the mechanical principles behind material phenomena. Mechanistic principles may "be as true in each [of God's worlds] as in this [possible] one."74 What happens to Descartes’s imaginary men and animals in this new universe can happen "in the actual world as well."75 Consequently, his "paper world" functioned as a locus for the development of clear and distinct understanding of mechanist principles that enabled the reader to judge for him/herself if, while created differently, these mechanisms might have analogs in the actual world.
The second function that this possible world served was aesthetic. According to Descartes, he used the "fable" of the possible world "so as to make this long discourse less boring." He wrote a "pleasing" story in order to enable "truth" to "manifest itself sufficiently clearly."76 Recall that, for Descartes, the value of poetic knowledge lay in the ability of the imagination to grasp the individual components of a narrative in an all-at-once kind of intuition (here of motion), thus enabling clear and distinct knowledge of a more complicated sort. As we saw earlier, the well-executed narrative of discovery teaches strong intellects the judgment needed for new discovery, and weaker intellects an aesthetic appreciation for such mental work. "Wrapping up" the "naked" philosophy made it possible for Descartes to present his reader with a unified and brightly shining alternative world.77 Descartes had hoped that this alternative world would be "useful to some," in so far as it presents an illuminating possibility and teaches the judgment necessary to undertake further discovery.78 For others, it was to have demonstrated the clarity and rigor of such imaginative understanding. While analogical discovery was clearly important to Descartes and the aesthetics of poetic knowledge gesture directly toward "weaker" intellects, there is a sense of excitement in the text that suggests that Descartes saw real innovation in poetically generated knowledge. The World "pleases" through "shading and bright colors," while making the nature of the epistemological "links" clearer than is possible in mimetic discourse. Descartes believed his fable facilitated higher-order knowledge and aesthetic judgment.79 His recognition of the danger posed by his "paper-world" speaks not only to the intellectual milieu of the mid-seventeenth century but also to the profound power he saw in poetic knowledge. Though he recognized the danger of such propositional writing, Descartes was "too much in love" with the beauty and rigor of The World completely to suppress the text. His new universe periodically appears in his more conventional and mimetic texts, a constant reminder throughout his empirical work that the realms of the possible were waiting to be discovered.
