The Duchess of Disunity: Margaret Cavendish on the Materiality of Mind

Introduction

We often feel torn, between love and hate, grief and joy, knowledge and ignorance, or belief and doubt. Sometimes we even love and hate the same thing at the same time. Philosophers as diverse as Plato, Ockham, Nietzsche, and Freud account for these puzzling conflicts by locating the contrary tendencies in different parts of our souls or selves.¹ Margaret Cavendish (1623–1673) belongs to this tradition of great dividers of the soul. She often casts her own ambivalence and uncertainty in terms of disputes between parts of her mind:

When I was setting forth this book of Observations upon Experimental Philosophy, a dispute chanced to arise between the rational parts of my mind concerning some chief points and principles in natural philosophy; for, some new thoughts endeavoring to oppose and call in question the truth of my former conceptions, caused a war in my mind … (OEP, 23; see also the Appendices in GNP)

Her “new thoughts” oppose her “former conceptions,” and she describes the various factions of her mind as parts with personalities and agendas of their own. While the language of parts might seem like a mere façon de parler, it is not. Cavendish holds that the mind is literally composite.

Cavendish turns the traditional arguments for partitioning the soul toward her materialist ends. She argues that, because the human mind is subject to conflicting tendencies, the mind must have parts and, therefore, must be material. In the Observations on Experimental Philosophy (hereafter Observations), she focuses specifically on passionate conflict:

the mind of man may be divided, so as to hate one person, and love another: nay, hate and love one and the same person, for several things, at the same time: as also rejoice and grieve at the same time. … for, the mind being material, is dividable as well as composable; and therefore its parts may as well oppose each other, as agree … (OEP, 145; my emphasis)

Loving and hating the same person at the same time is possible only, Cavendish holds, because the mind is divisible into parts and, hence, material.

Cavendish’s reasoning echoes Plato’s famous argument, in Book IV of the Republic, for the view that the soul has rational, appetitive, and spirited parts.² Plato appeals to the possibility of refusing one’s thirst to argue that the rational part of the soul is distinct from the appetitive part, and appeals to the strange desire to look upon the dead to establish that that the human soul includes a third, spirited part as well (Republic 439a-e). But, while Plato and Cavendish both attribute contrary tendencies to different parts, they disagree about what follows from this composite structure. Plato takes the soul’s tripartition to be consistent with the soul’s essential immateriality. Cavendish holds that having parts suffices for materiality. For Cavendish, mereological structure is a mark of the material, and the mental bears this mark. As Cavendish writes, “[r]ational parts … must of necessity have the Properties and Nature of a Body, which is to be divisible, and capable to be united, and so to be Parts” (GNP, 239).

Cavendish often claims that there is “no better proof” of the mind’s materiality than its disunity and complexity (PL, 69–70, 178, and 190), but, despite this, the existing scholarship on Cavendish lacks the kind of detailed reconstruction required to evaluate the merits of this argument.³ In this paper, I provide just such a reconstruction, focusing specifically on cases of passionate or emotional conflict.⁴ I also show that Cavendish’s argument is an effective intervention in her dispute with René Descartes and Henry More concerning the materiality of the mind.

Cavendish provides a refreshing counterpoint to arguments for the immateriality of the mind made by early modern figures such as Descartes, More, Ralph Cudworth, Gottfried Wilhelm Leibniz, and Samuel Clarke. According to these figures, when we reflect on our own minds, we discover a form of unity or oneness that is completely different from anything found in material things—an argument often referred to as the “Achilles.”⁵ Cavendish turns this argument upside down, saying that, when we look within, we find that we are often “of two minds,” torn, and divided against ourselves. This disunity, in her view, reveals our material nature. Cavendish’s alternative perspective helps to neutralize the dualist’s appeals to the supposed unity of the mind. Faced with the traditional Achilles, Cavendish joins her voice with other early modern critics of this argument, such as Anne Conway and John Locke, who emphasize the disunity and multiplicity of our minds.⁶ In short: Cavendish deploys a Reverse Achilles.⁷

1. Preliminaries

Before getting into the details of Cavendish’s argument, it will be useful to sketch her materialist system. Cavendish holds that “Nature is altogether Material” (PL, 12). Natural things such as mountains, rocks, sunflowers, dogs, and human beings are material things. Cavendish’s materialism is complicated, however, by her distinctive understanding of matter: whereas many early modern philosophers assume that matter is a single kind of mechanical or geometrical stuff, Cavendish distinguishes animate and inanimate degrees or kinds of matter (OEP, 24). Animate matter is active, self-moving, and perceptive; inanimate matter is passive, inert, and insentient.⁸ Animate matter explains the presence of motion and change in nature; inanimate matter explains the fact that bodies have “Gross Substance,” that is, sheer physicality and heft (PPO-1663, 2).

Cavendish further subdivides animate matter into rational and sensitive matter, which explain different features of natural motion or change. So, there are three degrees or kinds of matter in total: rational animate, sensitive animate, and inanimate (PPO-1663, xxxii; OEP, 16, 23–4; GNP, 3).⁹ The three degrees are thoroughly blended throughout nature (PPO-1663, 43; see also PL, 99 and 112; OEP, 16, 34–5, 127, 158, and 271).¹⁰ Everyday material things or bodies—mountains, rocks, sunflowers, dogs, human beings, etc.—incorporate all three. Everyday material things are the “effective parts” of nature, whereas rational, sensitive, and inanimate matter are “constitutive parts” (OEP, 27).

For Cavendish, the paradigmatic examples of natural change are end-directed processes, such as a sunflower turning toward the sun, or an acorn growing into an oak tree. The three degrees explain different aspects of such processes. Consider the building of a house: rational matter plays a role like that of the architect, sensitive matter that of the laborers, while inanimate matter corresponds to the building materials used (OEP, 24; see also PPO-1663, xxxii and 285).¹¹ Thus, rational matter sets the ends or goals, sensitive matter implements these ends, and inanimate matter is the stuff in which the ends are implemented. A complete explanation of a sunflower’s movements, for instance, requires (a) a rational principle internal to the sunflower that specifies the end of its movements, namely, turning toward the sun, (b) a sensitive principle that carries the plant toward the sun, and (c) an inanimate principle that is the stuff moved and carried.

A human being’s mind—the principle of thought, intellect, and rationality—is composed of rational matter. In Philosophical Letters, Cavendish writes that “the natural mind or soul” is “made of rational matter” (PL, 49). She reiterates that “this material or corporeal Mind is nothing else but what I call the rational matter” (PL, 192; see also 111, 116, and 434). And she explicitly applies this view to the human mind or soul: “the natural soul of man, which is part of nature … consists of the purest and subtlest degree of matter, which is the rational” (OEP, 190; see also 193 and 221). Cavendish often refers to a person’s mind and their rational matter in ways that indicate that she takes these to be equivalent.¹² Hence, we can discern her views on the mind by looking at what she says about rational matter.

If a human mind is simply an individual’s allotment of rational matter, then the mind is not an ordinary body or effective part, such as the brain, which we might dissect and study using normal empirical methods.¹³ We cannot cut open someone’s skull and see their mind (GNP, 10 and 21). Instead, the human mind is the rational aspect—a constitutive part, in Cavendish’s terminology—of a human being: the mind is the rational part “joy’nd and mix’d with the Sensitive and Inanimate Parts” (GNP, 21). The mind permeates the human body and regulates its movement in roughly the same way that rational matter regulates the movements of a sunflower.

For the purposes of this paper, we can largely bracket questions about precisely what kind of material thing the mind is. My aim is to answer the more basic question as to why Cavendish holds that the mind is material in the first place. This is somewhat orthogonal to whether the mind is a constitutive or an effective part.

2. Cavendish’s Reverse Achilles

To defend her material system of nature, Cavendish needs to show that the human mind is a material thing—a perennial challenge for the would-be materialist. Cavendish argues that mental conflict establishes that the mind is material. In the Observations, as I mentioned above, she appeals to cases of passionate conflict in which someone loves and hates the same thing at the same time:

[1] The sensitive and rational motions do often cross and oppose each other: for, although several parts are united in one body, yet are they not always bound to agree to one action; … And such an agreement and disagreement, is not only betwixt the rational and sensitive parts, but also [2] betwixt the rational and rational, the sensitive and sensitive. For some rational parts, may in one composed figure, have opposite actions; As for example, the mind of man may be divided, so as to … hate and love one and the same person … [3] for, the mind being material, is dividable as well as composable; and therefore its parts may as well oppose each other, as agree; for agreement and friendship is made by composition, and disagreement by division. (OEP, 145; numbering added)

Cavendish’s argument here proceeds in three main stages. First, she notes that sense and reason “do often cross and oppose each other” (ibid.). Second, she observes that reason can similarly oppose itself. Third, she argues that such rational conflicts can occur only if the mind is a material thing.

In Philosophical Letters, II.xv, Cavendish presents a more elaborate statement of this three-stage argument when criticizing Henry More’s view that the human mind is an “incorporeal substance” (PL, 177) or “Immaterial Spirit” (PL, 178).¹⁴ At the first stage, Cavendish considers a person whose sensitive appetite for wine conflicts with the rational desire for temperance as an example of conflict between sensitive and rational states:

But this is well to be observed, that some parts in some actions agree generally in one body, and some not; as for example, temperance and appetite do not agree; for the corporeal actions of appetite desire to join with the corporeal actions of such or such other parts [presumably, wine], but the corporeal actions of temperance do hinder and forbid it; whereupon there is a faction amongst the several parts: for example, a Man desires to be drunk with Wine; this desire is made by such corporeal actions as make appetite; the rational corporeal motion or actions which make temperance, oppose those that make appetite, and that sort of actions which hath the better, carries it, the hand and other parts of the body obeying the strongest side … (PL, 178, my emphasis; see also PPO-1663, 44–45)

A person’s sensitive appetite for wine and their rational desire for temperance oppose each other. The sensitive appetite and the rational desire push a person toward incompatible or contrary actions—namely, drinking and abstaining—that aim at different ends and force a choice upon us: between fleeting pleasure and one’s long-term good. Cavendish holds that these conflicting tendencies cannot arise from the very same source in a person’s psychology.¹⁵ Hence, this type of conflict is possible only if the sensitive appetite and rational desire originate in different parts of the person. As Cavendish puts it, when a person’s sensitive and rational tendencies conflict, there is a “faction amongst the several parts,” namely, their sensitive and rational parts (ibid.).

In the second stage of the argument, Cavendish notes that similar conflicts can occur within the mind or reason. As Cavendish writes, “some motions of the rational … may disagree amongst themselves” (PL, 179). That is, a person’s rational desires or tendencies can conflict with each other, just as much as with their sensitive appetites. This claim is more controversial than Cavendish’s initial observation that sense and reason can conflict because we might think that reason is internally coherent and that conflicts arise only when reason confronts external, alien forces. Plato, for example, appeals to conflicts between sense and reason to argue for the tripartition of the soul, but he would presumably deny that reason itself is vulnerable to strife and incoherence.

Reason conflicts with itself, according to Cavendish, when someone experiences contrary passions. Throughout her works, she maintains that passions—love, hate, joy, grief, and the like—are rational states.¹⁶ She often expresses this commitment by attributing the passions to rational matter: “Passions … Love, Hate, Fear, Joy, and the like, are made by the rational corporeal motions in their own degree of matter, to wit, the rational” (PL, 169–70; see also 44, 50, 57–58, 262). But the more basic point—that passions are rational—can be made independently of Cavendish’s materialist idiom. Thus, she writes that “Love, Hate, Anger, Joy, Hope, Doubt … and the like” are “thoughts in the Rational mind” (PPO-1663, 50). It follows that passionate conflicts are rational conflicts:

some motions of the rational, as well as the sensitive matter, may disagree amongst themselves, as we see, that a man will often have a divided mind; for he will love and hate the same thing, desire and not desire one and the same thing, as to be in Heaven, and yet to be in the World … (PL, 179; see also PL, 212, and PPO-1663, 260–61)

When someone loves and hates the same thing at the same time, this conflict arises within the house of reason—a house divided against itself.¹⁷

Just as the sensitive appetite for wine and the rational desire for temperance drive a person toward contrary ends and ways of acting, so too love and hate push in opposite directions. Love inclines someone to unite with their beloved, whereas hate drives them away. By parity of reasoning, Cavendish infers that these conflicting rational tendencies—love and hate—cannot arise from the same source within a person’s psychology and, therefore, must originate in distinct parts of a person’s mind.¹⁸

Having argued that the mind has parts, Cavendish moves, in the third and final stage of the argument, from the mind’s composite structure to the conclusion that it is a material thing. Materiality, for Cavendish, is a necessary condition for having parts: “without matter, there could be no parts” (OEP, 161). Moreover, she holds that “what has parts is divisible,” and that if something is divisible, then it is material (PL, 194; see also OEP, 125 and 263). “[I]mmaterials,” she explains, are “not capable … of being divided” (OEP, 35, my emphasis; see also GNP, 239). Indeed, Cavendish could not be more explicit that the parts of the mind—i.e., rational parts—must be material parts: “[r]ational parts … must of necessity have the Properties and Nature of a Body, which is to be divisible, and capable to be united, and so to be Parts” (GNP, 239).

Cavendish concludes that the human mind or soul is not “Immaterial, but Corporeal; not composed of raggs and shreds, but it is the purest, simplest and subtlest matter in Nature” (PL, 180).

We can reconstruct the core of Cavendish’s argument—focusing on stages two and three—as follows:

• 1. The mind or reason is the seat of the passions, such as love, hate, joy and grief.

• 2. Sometimes a person loves and hates the same thing at the same time.

• 3. Loving and hating the same thing are contraries.

• 4. If contraries modify something at the same time, then it must have parts.

  Therefore,

• 5. The mind or reason has parts.

• 6. If something has parts, then it is material.

  Therefore,

• 7. The mind or reason is material.

To bring out the force of Cavendish’s argument in the context of her dispute with Descartes and More about whether the mind is material or immaterial, I shall suggest that she can defend the key moves.

3. Is the Mind the Seat of the Passions?

Cavendish’s argument works only if the passions are genuinely states of the mind, because otherwise passionate conflict would not imply that the mind or reason conflicts with itself. We might object to the assumption that the passions are rational states, however, by appealing to the well-worn opposition between reason and passion or to the bodily character of many passions. An irrational fear of spiders, or a feeling of dread in the pit of one’s stomach, hardly seem like paradigmatic exercises of reason.

To make things even worse for Cavendish, her view that the passions are rational might seem internally unstable. Cavendish claims that the passions (love, hate, joy, grief, etc.) are virtually indistinguishable from the appetites (hunger, thirst, lust, etc.). Presumably, then, she should either classify both the passions and appetites as rational states or neither. And yet, Cavendish claims that the passions are rational states while the appetites are sensitive states and, hence, non-rational:

The Sensitive motions in making Appetites do so resemble the Rational motions in making of Passions, as there is Little difference, only the Sensitive matter and motions make Appetites on the Inanimate matter, and the Rational makes Passions on its own Substance. (PPO-1663, 263)

The Sensitive Appetites, and the Rational Passions do so resemble each other, as they would puzzle the most wise Philosopher to distinguish them; and there is not only a Resemblance, but, for the most part, a sympathetical Agreement between the Appetites, and the Passions … (GNP, 63)

If there is “Little difference” between appetites and passions, why does Cavendish attribute them to sense and reason, respectively (PPO-1663, 263)?

The answer is freedom.¹⁹ Cavendish attributes the passions to the mind because they exhibit the freedom that is characteristic of rational states. Rational states are freer—more voluntary—than sensitive states (PPO-1663, 3, 9, 58; GNP, 34, 62). The passions are free in the requisite sense: they are “voluntary actions of figuring” (OEP, 170; see also GNP, 59). Hence, the passions belong to the mind. Admittedly, Cavendish’s view has more than a whiff of paradox.²⁰ (How can the passions be actions? And how can the passions be free and voluntary, given that we are often swept away by love, hate, joy and grief?) But we can make sense of her position by recognizing that we love and hate for reasons. As Cavendish writes, “a Man may be in Love with a Woman for her Beauty, or Wit” (PPO-1663, 260, my emphasis; see also OEP, 145). A man may exert some control over his passions by reassessing his reasons for them. In contrast, we cannot argue our way out of being hungry.

The proposal, then, is that Cavendish classifies the passions as rational states because they respond to reasons. They may not be perfectly responsive, but they are responsive enough to qualify as expressions of our rational nature.

4. Do Our Passions Conflict?

The rational character of the passions implies that, if passionate conflict occurs, then the mind or reason conflicts with itself. Still, we might wonder whether such conflicts occur. Cavendish often treats passionate conflict as a psychological datum that does not require any special defense. In the Philosophical Letters (1664) and Observations (1666), she simply asserts that someone can feel contrary passions—such as love and hate, joy and grief, desiring and not desiring—toward the same thing at the same time (OEP, 146; PL, 179). In other passages, however, Cavendish seems more ambivalent about how deep passionate conflict goes. In the earlier Philosophical and Physical Opinions (1663), Cavendish suggests that we cannot love and hate the same thing in precisely the same respect at the same time:

As for Passion, we shall Love and Hate at one and the same Time, but not one and the same Thing at one and the same Time, for that is impossible. But Different Passions are made according to the Subjects or Objects they Move by or to, yet the Rational Animate matter, which Createth Passions, may Move partly Sympathetically, and partly Antipathetically, at one and the same Time; As for Example, a Man may be in Love with a Woman for her Beauty, or Wit, or Behavior, and yet have an Aversion to her Bad qualities; but a Man cannot Love the Person of a Woman, and Hate it at one and the same Time … (PPO-1663, 260; my emphasis)²¹

In this passage, Cavendish claims that although a man can simultaneously love a woman for her wit and hate her for her bad qualities, he cannot simultaneously love and hate her for her wit. This passage raises two questions. First, does Cavendish—between the Philosophical and Physical Opinions (1663) and the later works where she presents her argument for passionate conflict, the Philosophical Letters (1664) and the Observations (1666)—change her mind about whether we can love and hate the same thing at the same time? Second, would her denial of the starkest form of passionate conflict—loving and hating someone for the very same reason at the same time—undermine her argument from conflict to materiality? We might worry that loving and hating someone in relation to different features does not constitute a case of contrary passions, because the loving and the hating are not about the same thing. If a man loves a woman for her beauty and wit, and hates her for her bad qualities, then we might think that he loves and hates two distinct things: he loves her beauty and wit, he hates her bad qualities, so (we might think) there is no more conflict here than in a case in which someone loves jazz and hates cilantro.

My view is that Cavendish does not change her mind and that there is no problem for her argument. Even in the later texts, Cavendish holds that when we love and hate someone at the same time, we do so for different reasons or in different respects. In the Observations, she writes that “the mind of man may be divided, so as to … hate and love one and the same person, for several things, at the same time” (OEP, 145; my emphasis). The qualification “for several things” suggests that a man hates a person for one reason and loves them for a different reason. Hence, Cavendish does not change her view.

In response to the second question—which is really an objection—Cavendish can argue that loving and hating someone in different respects are contraries in the sense required by her argument. Love and hate do not simply skim over the surface of a person’s qualities. They reach all the way to the person herself. When a man loves a woman for her beauty and wit, he loves her. When a man hates a woman for her bad qualities, he hates her.²² Thus, when a man loves and hates a woman in different respects, his passions are not directed toward two distinct things like jazz and cilantro. The man’s emotional state is confounding because his conflicted feelings are about her.

Moreover, Cavendish can point out that loving a woman for her beauty and wit, and hating her for her bad qualities, are contraries in the sense that they drive a person toward incompatible or contrary actions. If a man loves a woman for her beauty and wit, he will be inclined to spend time with her. In the Grounds, for example, Cavendish claims that when a part loves another, it will “endeavor to keep their Society from dissolving” (GNP, 75). If a man hates a woman for her bad qualities, by contrast, he will tend to avoid her company. Not only can he not do both of those things at once, but these actions also have incompatible and contrary goals. While he can go to the jazz club and pass on the cilantro, he cannot isolate the woman’s beauty and wit from her bad qualities to interact with the former and not the latter. He must address the woman as an individual with all of her qualities.²³ Simply distinguishing the woman’s different aspects does not help to resolve the conflict.

Even if we grant that loving and hating someone in different respects are contraries in the sense required by Cavendish’s argument, we might still object that Cavendish cannot simply assume that we can undergo contrary passions at the same time, because one of her main targets, Descartes, rejects this assumption—he argues that conflicts never really occur within the mind. That is, he rejects premise (2) in the reconstruction above. Instead, he argues that conflicts occur at the nexus between mind and body as they play tug of war with the pineal gland:

All the conflicts usually supposed to occur between the lower part of the soul, which we call “sensitive,” and the higher or “rational” part of the soul—or between the natural appetites and the will—consist simply in the opposition between the movements which the body (by means of its spirits) and the soul (by means of its will) tend to produce at the same time in the gland. … It is to the body alone that we should attribute everything that can be observed in us to oppose our reason. So there is no conflict here except in so far as the little gland in the middle of the brain can be pushed to one side by the soul and to the other side by the animal spirits … (Passions, I.47; AT, XI, 364/CSM, I, 345–46)

On Descartes’s model, for instance, the mind’s judgment that it should abstain from drinking tends to suppress its desire for wine by turning the gland in one direction, while the body stirs up this desire by pushing the gland in the opposite direction.

Descartes recognizes, however, that our passions can seem to conflict. We can feel as if we are torn between desires for wine and temperance at the same time. He attempts to explain away the appearance of conflict by arguing that we mistake succession for simultaneity. When it feels as if we desire and reject the same thing at the same time, we are really oscillating between desiring and not. This oscillation, he says, “makes the soul feel itself impelled, almost at one and the same time, to desire and not desire the same thing. This is what has given people occasion to imagine that the soul has within it two conflicting powers” (Passions, I.47; AT, XI, 366/CSM, I, 346).²⁴ The appearance of conflict is illusory according to Descartes. ²⁵ The body can oppose reason. Reason cannot oppose itself.

Descartes and Cavendish agree, then, that there appear to be conflicts internal to the mind, but they disagree about the status of this appearance. Cavendish takes this appearance at face value: her explanation for it is that such conflicts occur. Descartes attempts to explain the appearance away in terms of the oscillation between contrary states of mind. Cavendish’s explanation has the advantage of simplicity. But simplicity is not decisive. To properly understand this dispute, we will need to consider why Descartes is so committed to denying that intra-mental conflicts occur. First, though, we need to grapple with another problem for Cavendish’s view.

5. Complexity and Materiality

Perhaps the most serious objection to Cavendish’s argument starts from the suggestion that she equivocates on what is meant by “part.” Her rationale for partitioning the mind is that it undergoes contrary passions toward the same thing at the same time—when a man loves a woman for her beauty and wit but hates her for her bad qualities, and cannot reconcile these passions, for instance. We might object that this rationale only licenses the attribution of parts or elements in a minimal sense—e.g., as faculties, powers, or, even more generically, distinct subjects of the conflicting tendences. Having parts in this minimal sense does not obviously imply that the mind is a material thing. Plato is an instructive case. He argues that the soul has parts but is nevertheless immaterial. Indeed, Shields (2010, 166–67) argues that Plato’s partitioning of the soul amounts to little more than the claim that the soul has multiple distinct aspects, which need not threaten its immaterial nature.

In response to this objection, I would like to suggest that Cavendish does not equivocate. Rather, her position is that the having of parts, even in a very minimal sense, implies being a material thing. If love and hate are contraries or opposites, then it follows that these passions require distinct subjects of inherence—distinct elements to which they belong—to prevent them from colliding.²⁶ This is plausibly an analytic or conceptual truth: what it means for F and G to be contraries is just that they cannot co-exist in a single subject of inherence. These distinct subjects or elements could be faculties or powers or whatever, so long as they can keep contraries separate. Thus, Cavendish’s appeals to passionate conflict imply that the mind contains parts in the sense of containing multiple subjects of inherence or elements. I think this is about as minimal a notion of part as you can get.

Here is the crucial point: Cavendish holds that if something contains multiple subjects or elements, then it is a material thing. She articulates this commitment when criticizing the view that the mind contains a multiplicity of faculties or powers, but nevertheless is immaterial:

if the Mind or Soul be Individable, then I would fain know, how Understanding, Imagination, Conception, Memory, Remembrance, and the like, can be in the mind? You will say, perhaps, they are so many faculties or properties of the Incorporeal Mind, but, I hope, you do not intend to make the Mind or Soul a Deity, with so many attributes, Wherefore, in my opinion, it is safer to say, That the Mind is composed of several active Parts …. (PL, 143)

Cavendish suggests that if the mind were an immaterial substance, then it would have to be radically simple, in something like the way God is traditionally supposed to be. If the mind were individable/immaterial, then it would not contain multiple distinct faculties or, more generally, multiple subjects of qualities, states, or modes. Thus, Cavendish holds that:

• 1. Something is immaterial iff it contains precisely one subject or bearer of qualities, states, or modes.

• 2. Something is material iff it contains more than one subject or bearer of qualities, states, or modes. (A painting, for instance, can be red here and green there.)

These principles—which are really the same principle formulated two ways—make Cavendish’s argument valid (which is an additional reason to attribute them to her). An immaterial thing would have to approximate divine simplicity. In the Grounds, for example, Cavendish argues that to be immaterial is to be divine, and that the divine is “Indivisible, and of an Incompoundable Being” (GNP, 241; see also 239). Passionate conflict reveals that our minds fall short of this standard.

Matter—materiality—was a contested concept in the seventeenth century.²⁷ Descartes famously argues that extension—or three-dimensionality—constitutes the nature or essence of matter (Principles II.4; AT, VIIIA, 42/CSM, I, 224). Other figures—such as Henry More—argue that there is more to matter than extension. We might wonder, then, whether anyone besides Cavendish will accept her principles connecting immateriality and unity, and materiality and multiplicity.

Descartes himself plausibly accepts these principles. In the Passions, Descartes denies that intra-mental conflict can occur, precisely because the mind is an immaterial substance. Underlying this denial is the principle that an immaterial substance incorporates precisely one subject or bearer of qualities, states, or modes. As Descartes explains, there are no conflicts within the soul because:

there is within us but one soul, and this soul has within it no diversity of parts: it is at once sensitive and rational too, and all its appetites are volitions. It is an error to identify the different functions of the soul with persons who play different, usually mutually opposed roles—an error which arises simply from our failure to distinguish properly the functions of the soul from those of the body. It is to the body alone that we should attribute everything that can be observed in us to oppose our reason. (Passions I.47; AT, XI, 364–65/CSM, I, 346)

When Descartes writes that “there is within us but one soul, and this soul has within it no diversity of parts,” he is saying that the soul lacks parts in even the very minimal sense discussed above. That is, the soul contains only one subject or bearer of qualities or modes (ibid.). Similarly, in Meditation 6, Descartes suggests that a person’s diverse thoughts belong to a single subject when he writes that “it is one and the same mind that wills, and understands, and has sensory perceptions” (M6, AT VII 86/CSM II 59). As Rozemond explains:

note how Descartes denies that the faculties of the soul are parts of it: he denies that there are several entities each of which is a distinct subject of inherence for a distinct type of mental state. Instead, he writes, “it is one and the same mind that wills, and understands and has sensory perceptions.” (Rozemond 2014a, 226)

Immaterial substances, for Descartes as for Cavendish, are radically simple beings. If any such substances exist, they would be single subjects of inherence.

Let’s take stock here. Cavendish and Descartes agree that:

• 1. Something is an immaterial thing iff it is a single subject of inherence.

• 2. Something is a material thing iff it contains multiple subjects of inherence.

They also agree that, if intra-mental conflicts occur—as when someone simultaneously loves and hates the same thing—then the mind would have to contain multiple subjects or bearers of qualities, states, or modes. Hence, they agree on the following conditional: if intra-mental conflict occurs, then the mind is a material thing. They disagree, however, about whether such conflicts occur: whether the mind or reason can oppose itself. Cavendish affirms this possibility; Descartes denies it—because he is committed to the mind’s immateriality.²⁸

Cavendish would likely have been familiar with these aspects of Descartes’s view. In the first edition of the Philosophical and Physical Opinions (1655), Cavendish reports not having read much Descartes except for his book on the passions (An Epilogue to my Philosophical Opinions in PPO-1655). A few years later, when Cavendish writes Philosophical Letters (1664), she claims to have read more of Descartes’s work in the interim: “The Authors whose opinions I mention, I have read, as I found them printed, in my native Language, except Des Cartes, who being in Latine, I had some few places translated to me out of his works” (PL, A Preface to the Reader, unnumbered page). Descartes may well have inspired Cavendish’s argument from passionate conflict. Perhaps Descartes’s modus tollens is Cavendish’s modus ponens.²⁹

6. More’s Extended Spirits

Even though Henry More is Cavendish’s explicit target in Philosophical Letters, II.xv, her argument from passionate conflict seems less effective against his version of dualism (PL, 177). Unlike Descartes, More holds that all substances are extended, spirits and bodies alike. As More writes, “there is no Substance but it has in some sort or other the Three dimensions” (Immortality, I.2, 12; see also I.3, 17).³⁰ More distinguishes material and immaterial things in terms of divisibility and penetrability. Material substances are divisible and impenetrable, whereas immaterial substances are indivisible and penetrable. Divisibility/indivisibility is the criterion most relevant to Cavendish’s disagreement with More. A body, such as a lemon tart, can be sliced and the pieces can exist on their own. A spirit, such as a human soul, cannot be sliced up. As More writes, the parts of a spirit “hold so fast together, that they are by no means Discerpible” (Immortality, I.3.2, 17). Just as rays of light cannot “be clipt off, or cut off from” their source, the parts of an immaterial substance cannot be divided and “kept apart by themselves” (Immortality, I.5.2, 27).

For those of us steeped in Descartes’s philosophy, More’s extended spirits might seem odd, if not downright contradictory, but Casper the friendly ghost provides a model. Casper has a shape and is therefore extended. His ability to glide through walls suggests that he can co-locate with other things and is, therefore, penetrable. If Casper could not be sliced into two separately existing blobs of ectoplasm, he would also be indivisible. Casper, then, is extended, penetrable, and indivisible: an immaterial substance by More’s lights.

Given More’s conception of immaterial substances, the conclusion that the mind has parts—indeed, spatially extended parts—in no way jeopardizes its immateriality. Mereological structure is baked into More’s account of immaterial things. Indeed, More explicitly argues that the human mind is extended throughout the body by appealing to cases of passionate conflict that resemble Cavendish’s. In Immortality (II.10.6, 220), More observes that we often experience passions when we would prefer not to: “it is evident that [passions] arise in us against both our Will and Appetite. For who would bear the tortures of Fears and Jealousies, if he could avoid it?” He reasons that contrary passions—such as fear and the desire not to be afraid—cannot originate from a single psychological source, arguing that the soul “as she resides in the Heart and Stomack” produces fear and jealousy, whereas the soul “as she resides in the Head” desires to be free of these passions. In other words, he accounts for psychic conflict by locating opposing passions or drives in different spatial parts of the soul. In effect, he runs with premises (1)–(5) in Cavendish’s argument. The only premise he rejects is premise (6): if something has parts, then it is material.

Cavendish takes up More’s argument in Philosophical Letters, II.27:

Moreover, says he [More], Passions and Sympathies, in my judgment, are more easily resolved into this hypothesis of the Soul’s pervading the whole body then in restraining its essential presence to one part therefore. — But it is evident that they arise in us against both our will and appetite: For who would bear the tortures of fears and jealousies, if he could avoid it? (PL, 212)

She agrees with More that passionate conflict implies that the mind or rational soul has parts and even that these passions occur in the heart, but she insists that the spatially extended mind is a material thing: “I have given my opinion at large in my book of Philosophy, and am of your Authors mind, that Passions are made in the Heart, but not by an Immaterial spirit, but by the Rational soul which is material” (PL, 212; see also PPO-1663, 262).³¹

Cavendish and More seem to be at a stalemate. They both attribute parts to the mind/soul because of passionate conflict. But they draw strikingly different conclusions from the claim that the mind has spatially extended parts. For Cavendish, this is conclusive evidence that the mind is a material thing. For More, this result is perfectly consistent with the mind’s immateriality. The crux of their disagreement is about whether the mind is divisible and, more generally, whether composite things are necessarily divisible into their parts and, hence, material. Cavendish says yes, but More says no. Cavendish recognizes this point of disagreement, noting that More “believes the Mind or rational Soul to be individable” (PL, 177). Thus, to establish that the mind is material by More’s standards for materiality, Cavendish needs to show that the mind is not just composite, but also that it is decomposable: not just that it has distinguishable parts, but that it is divisible into its parts.

Cavendish often moves directly from the claim that something has parts to the conclusion that it is divisible, without providing any justification for this transition. She often suggests that materiality, extension, compositeness, and divisibility go hand in hand:

without matter, there could be no parts, and so no divisions (OEP, 161)

there is no substance in Nature that is not divisible; for all that is a body, or a bodily substance, hath extension, and all extension hath parts, and what has parts, is divisible (PL, 194)

whatsoever has body, or is material, has quantity; and what has quantity is divisible (OEP, 125)

Wheresoever is body, there are also parts; so that divisibility is an essential propriety or attribute of matter or body (OEP, 263)

For Cavendish, it is a conceptual or obvious truth that something is material iff it is extended iff it has parts iff it is divisible. These properties come as a package for Cavendish. More, in contrast, denies that compositeness or extension entail divisibility or materiality.

To reach a philosopher like More, Cavendish could use at least two strategies to show that the mind is divisible into its parts and, hence, material. First, she might argue that it is conceivable and, therefore, possible that the mind be divided. Specifically, given More’s view that spirits are extended, Cavendish might adapt Descartes’s argument in Principles I.60 that if anything is extended, then we can conceive of it being cut in half, which implies its divisibility (AT, VIIIA, 28/CSM, I, 213). We can conceive of slicing Casper in half, for example. Second, she might produce an example in which the mind is in fact divided to show that the mind is divisible—that is, she might offer an example of actual division as proof of possibility. Cavendish pursues the second strategy. Let us take another look at her statement of the argument from passionate conflict in the Observations:

the mind of man may be divided, so as to hate one person, and love another: nay, hate and love one and the same person, for several things, at the same time: as also rejoice and grieve at the same time. … for, the mind being material, is dividable as well as composable; and therefore its parts may as well oppose each other, as agree … (OEP, 145; my emphasis)

When someone loves and hates the same person, Cavendish says that the mind is divided and, therefore, divisible. Similarly, in the Philosophical Letters, Cavendish writes that “a man will often have a divided mind, for he will love and hate the same thing” (PL, 179; my emphasis). She uses actual division as proof of the mind’s divisibility.

The question, then, is why Cavendish classifies these as cases of actual division. The claim that the mind is divided implies that the loving part of the mind is divided or separated from the hating part. In other words, the loving and hating parts do not form a whole. Thus, we can make sense of Cavendish’s suggestion that love and hate divide the mind by considering the conditions under which parts form a whole. These conditions are a subject of scholarly debate. Peterman (2019, 491–97), for instance, argues that part-whole facts are brute for Cavendish. Other scholars, such as Lascano and Schliesser (2022, 176–77, 186, 193), argue that Cavendish employs the concept of a functional whole—most notably, in the case of human beings—according to which a collection of parts form a whole in virtue of working together. Although I am sympathetic to Peterman’s (2019) claim that some part–whole facts are primitive for Cavendish, I think that Lascano and Schliesser are right that not all such facts are primitive and, moreover, that Cavendish sometimes appeals to the concept of a functional whole.

As I read Cavendish, she holds that a collection of mental states composes a single mind or unified experience in virtue of tending toward a common end or goal. In the Observations, for example, she appeals to this principle of composition to explain the puzzle of binocular vision, namely, to explain how visual input from two or more eyes can result in a unified visual experience. “[I]f a thousand eyes do perceive one object just alike,” Cavendish explains, “then they are but as one eye, and make but one perception; for like as many parts do work or act to one and the same design; so do several corporeal motions in one eye, pattern out one object” (OEP, 183; my emphasis). Similarly, in the Grounds, Cavendish suggests that sensory perceptions in different modalities—seeing, hearing, touching, etc.—are united into a single experience in virtue of the fact that these perceptions serve a common end:

As I say, That every several composed Perception, was united to the proper use of the whole Society, as one Man … although these several Organs [of sense] are not perfectly, or thoroughly acquainted; yet in the Perception of the several parts of One object, they do all agree to make their several Perceptions, as it were by one Act, at one point of time. (GNP, 53; my emphasis; see also PPO-1663, 54)

On this model, the unity of the mind is a functional unity. The parts of the mind form one thing in virtue of functioning together to achieve one end (e.g., the preservation of the organism).

The proposal, then, is that when someone loves and hates the same thing, the loving and hating parts of their mind are divided because they aim at different ends. In these cases, our minds literally divide in two, with one part going in one direction, and the other in a different direction. Consider, again, the man who loves a woman for her beauty and wit and hates her for her bad qualities. His love aims at spending time with this woman, his hatred aims at avoiding her. His mind is literally divided to the extent that its parts fail to function together. This fits nicely with Cavendish’s metaphors of wars and factions within the mind (PL, 212). Thus, Cavendish might claim—pace More—that cases of passionate conflict establish that the mind is divided and, hence, divisible.

Granted, Cavendish is using her own account of the conditions under which parts of the mind are united/divided, and it is not clear that More would accept this. But I think that Cavendish’s strategy is nevertheless quite brilliant: it shows that the mind is divisible by producing an instance of actual division, embedded within a broader account of the union and division of parts.

If our minds literally split in two in cases of passionate conflict, we might object that it is no longer one person who is torn in two directions. The multiplicity in unity is precisely what makes passionate conflict so puzzling. We might worry that we have lost sight of this phenomenon. In response to this objection, Cavendish could argue that there is one organism—one human being—with two minds. The common expression “I am of two minds about this” captures the situation nicely, as it expresses the singular “I”—referring to the organism—and the duality of minds. Alternatively, she might point out that unity and division can come in degrees, especially when we are dealing with functional unities. For instance, the loving and hating parts might be united to the extent that they both aim at the good of the whole human being and divided to the extent that they disagree about how to achieve this shared aim. The loving part sees happiness in spending time with the woman, the hating part in avoiding her. Although there is clearly more to be said about the unity of the Cavendishian mind, a full account is beyond the scope of the current paper. Any adequate reading, however, must pay close attention to the possibilities of mental division to which Cavendish is so keenly sensitive.

Conclusion

Reflection on one’s own thoughts and experiences might seem to favor an immaterial view of the mind. When we reflect on our mental lives, we might be so impressed by the unity we discover that we are tempted to conclude—with Descartes and More—that our minds could not possibly be material. An apparent gulf separates the unity of the one and the same I who doubts, understands, desires, denies, wills, imagines and senses, and the multiplicity of a heap of sand or a pile of bricks. Cavendish’s Reverse Achilles argument suggests a different perspective. We often describe our ambivalence by saying that we are torn, of two minds, or divided against ourselves. For Cavendish, these descriptions track the composite structure of our minds. When we feel ourselves pulled in different directions, we discover that we have parts that can be pulled in this way and perhaps even exist apart. We discover different selves in our selves, with different beliefs, passions, and commitments. What is it like to be a material thing? Turn inwards. Consider what it is like to be you. Consider the way your mind “may be divided, so as to hate one person, and love another; nay, hate and love one and the same person, for several things, at the same time” (OEP, 145). Consider the multitudes you contain, the hidden depths, the contradictions, and the dissonance. That is precisely what it is like to be a material thing. Or so argues the Duchess of Newcastle.³²