2. ‘Consciousness’ in the Ethics

In the Ethics, Spinoza uses the Latin words ‘conscius’ and ‘conscientia’ but never formally defines them. As Jon Miller (Reference Miller2007: 208) points out, unlike key concepts such as ‘substance’, ‘attribute’, and ‘intuitive knowledge’, Spinoza leaves ‘consciousness’ unexplained.

This situation presents a peculiar challenge: we must attempt to reconstruct Spinoza’s account of consciousness without being told what it is. As such, scholars have long debated whether Spinoza even has a theory of consciousness; however, no consensus has been reached. This situation is reflected in the opening remarks in Steven Nadler’s famous paper ‘Spinoza on Consciousness’, which claims that ‘most discussions of Spinoza and consciousness conclude either that he does not have an account of consciousness, or that he does have one but that it is at best confused, at worst hopeless’ (Reference Nadler2008: 575).Footnote ⁴ While Spinoza does not formally define consciousness, his use of ‘conscius’ and ‘conscientia’ points to two main contexts in which the notion appears.

3. Theories of consciousness

This reflexive model has led some commentators to interpret Spinoza as offering a robust theory of consciousness. Edwin Curley, for example, sees in Spinoza’s doctrine of the ideas of ideas an account of the theory of consciousness. Curley claims that consciousness begins when we can reflect on our ideas, or when an idea takes another idea as its object (Reference Curley1969: 128). He wants to use the doctrine of the ideas of ideas to distinguish conscious mental states from non-conscious mental states. However, others have argued that the ‘ideas of ideas’ theory cannot establish the doctrine of consciousness in Spinoza since ideas of ideas are united to every mode of thought.Footnote ¹⁹ Indeed, for Spinoza, as the order and connection of ideas is the same as that of things (Eth, II, 7: 450/G, II, 89), thought extends everywhere.Footnote ²⁰ Thus, if the reflexivity of ideas were the hallmark of consciousness, then every idea would be a conscious thought.Footnote ²¹

Against Curley’s proposal, Nadler argues that consciousness is the complexity of the body expressed under the attribute of thought (Reference Nadler2008: 587). Nadler bases his argument on two key passages: E2p13s and E5p39s. While in E2p13s, Spinoza connects the capability of a body to do many things to the capability of its mind to perceive many things at once, in E5p39s, he links the capability of a body to do many things to the degree of consciousness of its mind. While this proposal allows for minds to be more or less conscious (e.g. a jellyfish would be less conscious than a dolphin because of the lesser complexity of its body), this theory is not unproblematic either.Footnote ²² How, for instance, could the complexity of a body determine whether its mind is conscious?

Don Garrett (Reference Garrett and Huenemann2008: 4–25) claims that while complexity can say something about consciousness, it cannot constitute it. According to Garrett, consciousness should be identified with the power of thinking: an idea is conscious when it reaches a certain degree of power. As evidence that consciousness is related to the power of thinking, Garrett draws on the same two passages as Nadler – E2p13s and E5p39s – and also references E5p31s, where Spinoza states, ‘the more each of us is able to achieve in this kind of knowledge, the more he is conscious of himself’ (Eth, V, 31, schol.: 610/G, II, 300).

Garrett’s interpretation is more promising for several reasons. First, it explains why some minds are more conscious than others. If a mind’s consciousness is grounded in its power of thinking, it follows that the greater one’s engagement with the third kind of knowledge, the greater one’s consciousnessFootnote ²³ (Eth, V, 42, schol.: 616/G, II, 308). Second, this framework allows for a distinction between conscious and non-conscious mental states: only sufficiently powerful ideas – those that significantly affect the mind – are conscious.Footnote ²⁴

However, this interpretation is not without challenges. Notably, E5p31s and E5p39s are problematic foundations for a general theory of consciousness. These passages address a specific form of consciousness associated with the third kind of knowledge, which pertains exclusively to the eternal part of the mind: the intellect. As Michael LeBuffe aptly observes (Reference LeBuffe2010: 559), the texts Garrett relies on cannot support his broader claims. In particular, E5p39s addresses conscious knowledge, making it unsuitable as a comprehensive account of consciousness.

This survey highlights a persistent challenge scholars face when attempting to attribute a robust theory of selective consciousness to Spinoza. The root of this problem lies in the absence of a formal definition of ‘consciousness’ in any of the passages where the term appears. This absence makes reconstructing Spinoza’s account of consciousness particularly difficult.

Nevertheless, this ambiguity should not discourage us from further investigations. Lia Levy suggests that rather than seeking a definitional account of consciousness in Spinoza, we should investigate its causal structure. In other words, instead of asking what consciousness is, we should ask what its causal explanation is. Her argument is based on the fact that, in the Ethics, we find the expression ‘causa conscientiae’ (‘cause of consciousness’) (Eth, III, AD, 1, expl.: 531/G, II, 190). In that context, Levy explains, Spinoza does not define consciousness, but rather identifies the conceptual conditions under which consciousness emerges. For Levy, this passage supports the view that ‘Spinoza conceives of consciousness as necessarily related to existence in duration, in the sense that only thinking things that exist in duration can be conceived as conscious beings’ (Reference Levy and Yitzhak2017: 189).

I contend that this conclusion is difficult to square with the textFootnote ²⁵ and with what we considered in Section 2.3. How can one argue that the phenomenon of consciousness is only attributable to duration when Spinoza explicitly writes that the wise man, who knows through the third kind of knowledge, is ‘by a certain eternal necessity, conscious of himself, and of God, and of things’ (‘sapiens sui, et Dei, et rerum aeterna quadam necessitate conscius esse’) (Eth, V, 42, schol.: 617/G, II, 308)? While Levy’s focus on causality is helpful, I suggest that it needs to be extended to account for Spinoza’s view that consciousness can transcend duration altogether.

4. Consciousness and eternity

It is impossible to deny the conceptual relationship between consciousness and the mind’s eternity when one examines the co-occurrences of these terms. The first observation that should alert the sceptical reader to the presence of consciousness in eternity is that in Part V of the Ethics, all occurrences of the expression ‘conscius esse’ (‘to be conscious’) are gathered together in the second half of the section (just after proposition 20).Footnote ²⁶ This proposition is rightly considered a crucial juncture in the text, as Spinoza subsequently delves into the third kind of knowledge and the mind’s eternity.

As we have already seen, Spinoza frames the conclusion of the Ethics around an opposition between modes of consciousness: the opposition between the ignorant person who lives quasi inscius (unaware) and the wise person who is conscius (conscious) (Eth, V, 42, schol.: 616-617/G, II, 308). It is in E5p31s, however, that Spinoza makes an ironclad link between consciousness and the mind’s eternity.

Proposition 31 is important because Spinoza establishes there that the third kind of knowledge ‘depends on the mind insofar as the mind itself is eternal’ (Eth, V, 31: 610/G, II, 299). Within the proposition itself, Spinoza maintains that the mind, insofar as it is eternal, is the adequate cause of the third kind of knowledge; in the scholium, he contends that ‘the more each of us is able to achieve in this kind of knowledge, the more he is conscious of himself, and of God’ (Eth, V, 31, schol.: 610/G, II, 300). Given that the third kind of knowledge follows from the eternity of the mind, it is closely linked with the mind’s eternity and its eternal form of consciousness.

However, this conceptual relationship between consciousness and eternity can be understood completely only if the causal relationship between them is established (Della Rocca Reference Della Rocca2008: 1–12). We can genuinely claim to understand the nature of something only if we can assign a cause or reason for its existence and nonexistence.Footnote ²⁷ Accordingly, Spinoza’s notion of consciousness cannot evade the principle of sufficient reason: if we locate a conceptual connection in the text between consciousness and eternity, then we must make explicit the cause which explains the existence of consciousness in eternity. Only then can we make the notion of eternal consciousness fully coherent in Spinoza’s philosophy.

5. Consciousness and its cause

Three expressions in the Ethics are relevant to the cause of consciousness. The first expression indicates that ‘the mind is necessarily conscious of itself through (per) ideas of the body’s affections’ (Eth, III, 9, dem.: 500/G, II, 147). The second expression almost exactly reproduces the first, but changes the subject to the man rather than the mind (Eth, III, 30, dem: 510–511/G, II, 163). The third expression reads as follows: ‘in order to involve the cause of consciousness, it was necessary to add: insofar as it is conceived, from some given affection of it, to be determined, and so on’ (Eth, III, AD, 1 expl.: 531/G, II, 190). Do these propositions tell us anything explicit about the cause of consciousness in eternity?

I believe they do not. While Spinoza connects consciousness with eternity in Part V, these three passages are from Part III, titled ‘Of the Origin and Nature of the Affects’, where consciousness is treated as a durational phenomenon. This is for two main reasons. First, in Part III, Spinoza provides two definitions of affect, both of which relate this notion to change over time.Footnote ²⁸ Second, in E3p9d, Spinoza identifies the object of a conscious mind as the conatus, namely, the essence of a thing as it exists in time.

This leads us to a crucial point. In E3p7, Spinoza explains that conatus is the ‘actual essence of the thing’ (Eth, III, 7: 499/G, II, 146). In this context, ‘actual’ is a temporal notion referring to what exists in relation to a certain time and place.Footnote ²⁹ Conatus, in fact, is the tendency that each thing has to exist for an indefinite time when external circumstances permit this existence (Eth, III, 8: 499/G, II, 147). In a nutshell, a thing’s conatus is not its eternal essence, but its essence as it exists in time. The word refers to a thing’s effort to persist across an indefinite duration. In this respect, conatus is what Spinoza calls the ‘actual essence’ of a thing. By contrast, the ‘formal essence’ of a thing is eternal.Footnote ³⁰ Sometimes, Spinoza explicitly uses the expression ‘formal essence’ to refer to the eternal character of an essence in contraposition to the durational existence of a thing; that is, its conatus. For example, in E2p8, he uses the expression ‘formal essence’ (‘essentia formalis’) to indicate those things that do not exist in duration but only in God’s attributes.Footnote ³¹

This distinction is key to Levy’s interpretation. In her reading of E3AD1expl (Reference Levy and Yitzhak2017: 197), Levy argues that for Spinoza, consciousness emerges not from the formal constitution of the essence but through a continuous temporal process of its determinations: one affection determines the actual essence that a prior affection in time has already determined.Footnote ³² According to Levy, this interpretative lens helps illuminate why, in E3AD1expl, Spinoza feels compelled to clarify what causes the man to be conscious of his desire.

While we already know that the mind is conscious of its striving (conatus), that this striving, when related to the mind and the body, is termed ‘appetite’, and, finally, that appetite, when conscious, is termed ‘desire’, Spinoza insists on a further specification. He explains that consciousness arises when the human essence is determined by any given affection. Therefore, the essential condition for explaining the onset of consciousness is the presence of a certain affection that determinesFootnote ³³ our essence. This conclusion revolves around a notion of ‘cause’ that evokes an ontological dependence – a process between two or more beings that, in this case, are determinations or affections of the essence.

On this view, the cause of consciousness is a structured ontological dependence between successive determinations of the actual aspect of the human essence. In a nutshell, consciousness is always the effect of a chain of determinations of our actual essence. For this reason, Levy argues that understanding the cause of consciousness entails that ‘it is necessary to consider the several configurations that shape the existence in duration of this essence’ (Reference Levy and Yitzhak2017: 199). However, from Levy’s perspective, this implies that ‘Spinoza conceives of consciousness as necessarily related to existence in duration, in the sense that only thinking things that exist in duration can be conceived as conscious beings’ (Reference Levy and Yitzhak2017: 189).

I find Levy’s interpretation compelling and well-supported by textual evidence. The merit of her analysis lies in her identification of the cause of consciousness with ‘an immanent movement of determinations’ of the essence (Reference Levy and Yitzhak2017: 199). She shows that the inside-outside approach, according to which we are conscious only when impinged upon by external bodies, must be replaced by an internal determination of the various constitutions of our actual essence (conatus) insofar as it strives to endure. However, we may yet reject her broader conclusions. For example, can consciousness arise outside the order of duration? Is there, for Spinoza, a kind of consciousness that is not generated by the determination of our temporal essence, but instead arises from our eternal essence?

My claim is that if the cause of consciousness in duration requires us to focus on the internal determination or affection of the actual essence, then a parallel causal structure can be found in eternity, where the formal essence can determine itselfFootnote ³⁴ through its affectionFootnote ³⁵ – namely, the amor Dei intellectualis.

This position, in my view, complements rather than contradicts Levy’s interpretation. It respects Spinoza’s insistence that ‘eternity cannot be explained by duration’ (Eth, I, 8, def.: 409/G, II, 46; Eth, V, 29, dem.: 609/G, II, 298) and thus calls for a dual explanatory framework: one for consciousness as it arises in duration and another for consciousness as it arises in eternity.

6. Amor Dei intellectualis and consciousness in eternity

In the previous section, I showed that for Levy, durational consciousness is the effect of the immanent chain of determinations of the actual essence.Footnote ³⁶ I now want to extend that model to eternity. Indeed, in E3AD1expl, Spinoza argues that the conceptual condition for explaining consciousness is causal determinacy. More specifically, the human essenceFootnote ³⁷ should be considered as determined by its affections, but with the specification that by affection, we understand any constitution of the essence, whether it is innate or has come from outside. The fact that Spinoza uses the word ‘any’ (‘quamcunque’) in reference to the expression ‘constitution of that essence’ suggests that the reference is not only to the temporal constitution of the essence, but that any constitution of the essence, even the eternal or formal, can be considered.

Thus, my claim is that eternal consciousness arises when the human essence, in its formal constitution, is conceived as determined by the amor Dei intellectualis. However, this determination is a self-determination of the essence since the eternal essence is determined by its own affection – its amor Dei intellectualis – which it causes, insofar as it is internally determined,Footnote ³⁸ as its adequate cause rather than being externally determined by fortuitous encounters with things.

In E2p29s, Spinoza explains that when we are not ‘determined externally, from fortuitous encounters with things’, we can be ‘determined internally’ (Eth, II, 29, schol.: 471/G, II, 114). Now, the internal determination Spinoza refers to is nothing but the causal efficacy of the formal constitution of our essence. Spinoza believes that the essence of a thing is expressed by its definition (Eth, I, 33, schol., 1: 436/G, II, 74). Both the essence and the definition have a precise structure or constitution. However, since ‘from everything which exists some effect must follow’ (Eth, I, 36, dem.: 439/G, II, 77), just as certain properties follow from the definition of a thing, certain effects follow from the formal essence of a thing.Footnote ³⁹ Consequently, when a thing is considered regarding its formal essence, or as Charlie Huenemann writes, ‘in isolation from his particular surroundings, circumstances, ancestors, and descendants’ (Reference Huenemann, R.J. and C.1999: 235), it can be considered the adequate cause of all the effects that follow from itself.

To be an adequate cause is to have within oneself everything needed to understand adequately a certain effect as a necessary consequence of that cause (Eth, III, def., 1: 492/G, II, 139). In other words, when we are the adequate cause of a certain effect, that effect follows from the formal constitution of our essence insofar as the essence has complete ownership of it, since it is not determined by something from the outside. Indeed, all the effects that follow from our essence considered in its formal constitution belong to us precisely because they are properties determined by our nature, in the same way that it is a property of a triangle that the sum of its interior angles is equal to two right angles.

Spinoza also speaks of affects as things that can follow either entirely from our own nature – insofar as we are their adequate cause – or because we are partial causes – insofar as we are their inadequate cause (Eth, III, def., 2: 493/G, II, 139). Alexander Douglas’s excellent paper on how to make passions active puts the point in this way. Douglas writes that according to Spinoza, ‘a subject, S, is the adequate cause of an affect, A, if A can be clearly and distinctly understood through S’ (Reference Douglas2019: 241). For Douglas, ‘through’ refers to predication: ‘a mode is understood through the substance of which it is the mode. A quality is understood through the object of which it is a quality’ (Reference Douglas2019: 241). The same meaning must then apply to the affects: when we ‘form a clear and distinct idea of an affect, we make it our action’, and we thus ‘understand the affect to be predicated of us, belong to us – to really be ours’ (Reference Douglas2019: 242). ‘An affect, then’, Douglas concludes, ‘is our action if we understand it to be predicated of us. It is our passion if we don’t understand it as belonging to us’ (Reference Douglas2019: 242).

I contend that the deduction of the amor Dei intellectualis shows exactly what Alexander Douglas argues in his paper; that is, the possibility for the human essence conceived in its formal constitution to be the adequate cause of an affect of which it has full ownership insofar as it can be predicated of it.Footnote ⁴⁰ For this reason, I argue that the amor Dei intellectualis is the affection of the essence that determines the human essence, and is thus responsible for the causal process from which eternal consciousness arises.Footnote ⁴¹ To see this more clearly, let us consider how Spinoza deduces the amor Dei intellectualis from our essence and whether it is true that our essence is its formal cause.Footnote ⁴²

After E5p20s, Spinoza’s Ethics deals with the third kind of knowledge, the mind’s eternity, its beatitude, and the deduction of amor Dei intellectualis. Regarding this last point, Spinoza’s statement in E5p32c is clear: from the third kind of knowledge arises a ‘joy accompanied by the idea of God as its cause, that is, love of God’ (Eth, V, 32, cor.: 611/G, II, 300). The deduction of the amor Dei intellectualis is grounded in two main theoretical elements: joy and love (Matheron Reference Matheron1997: 236; Melamed Reference Melamed2019: 227–228).

Regarding joy, E5p32d refers the reader to E5p27, where Spinoza writes that ‘the greatest satisfaction of mind there can be arises from this third kind of knowledge’ (Eth, V, 27: 609/G, II, 297). E5p27d involves multiple steps. First, Spinoza states that ‘the greatest virtue of the mind is knowing God or understanding things through the third kind of knowledge’ (Eth, V, 25: 608/G, II, 296). This greatest virtue takes the form of a passage to the greatest human perfection. However, since Spinoza defines the passage from a lesser to a greater perfection as a joy (Eth, III, AD, 2: 531/G, II, 191), he can assert here that this greatest virtue is a joy. However, given that the idea of oneself accompanies this joy as its cause, this joy is self-esteem (Eth, III, AD, 25: 536/G, II, 196). How can Spinoza state that this joy is self-esteem?

It is extremely interesting to note Spinoza’s use of E2p43 in E5p27d, in this initial stage of the deduction of the amor Dei intellectualis, to establish that the consciousness inherent in the true idea leads us to contemplate ourselves as the real cause of our joy. Why does Spinoza employ E2p43 in this way? The reason can be found in the fact that Spinoza here establishes that the consciousness of an idea is inherently tied to a true idea, which is explained through the nature of the human mind (Eth, II, 43, dem.: 479/G, II, 123). Once we have a true idea, we are aware that we have it and that we are its cause.Footnote ⁴³ If, however, we are the cause of this kind of knowledge and of the joy that results from an awareness of this, we rejoice, for we are aware that we are the cause of that passage that has brought us to the greatest perfection.

At this juncture, we encounter an affect of joy that is intertwined with consciousness of ourselves as its cause. This suggests that we encounter an active affect that inherently involves consciousness and can be, as Alexander Douglas observed, predicated of us insofar as we are its adequate cause. Does this bring us to the solution we sought – namely, the deduction of consciousness in eternity? In short: no. Spinoza indeed deduces our greatest joy from us as the cause of this joy, but it is equally true that he characterises this joy as a transitio (passage) in this phase regarding the deduction of intellectual love. We have not yet arrived at the point where we experience an affect that is not a temporal passage. Let us consider, then, how Spinoza demonstrates that this joy is an eternal love that bears the name of amor Dei intellectualis.Footnote ⁴⁴

As we can see from our current analysis, in E5p27d, Spinoza highlights the autonomy that the individual achieves through the third kind of knowledge. This form of knowledge generates ‘the greatest joy’, which arises from the awareness that the individual is the cause of their own happiness. However, given that the third kind of knowledge necessarily implies both knowledge of God and knowledge that we are in God (Eth, V, 30: 610/G, II, 299), in E5p32 and its demonstration, Spinoza reintroduces the notion of God as the cause of the greatest pleasure arising from the third kind of knowledge. This arises from the fact that whatever we understand by the third kind of knowledge generates joy within us, accompanied by the idea of God as the cause of that joy. In the subsequent corollary to the same proposition, Spinoza explicitly states that the joy in question is, in fact, love – specifically, the amor Dei intellectualis (Eth, V, 32, cor.: 611/G, II, 300). How does Spinoza move from (temporal, internally caused) joy to the (eternal) intellectual love of God? This transition is possible because love is simply joy accompanied by the idea of its cause. As Clare Carlisle aptly observes, ‘love always has a cognitive element since it involves the idea of a cause’, and this characteristic ‘generates a threefold taxonomy of love’ (Carlisle Reference Carlisle and Melamed2021a: 442). Joy can be attributed to a cause that we know through imagination, reason, or intuition; the love of God belongs to the last category. Spinoza thus refers to God’s eternal love as the intellectual love of God.

Nonetheless, it is interesting to examine how Spinoza demonstrates that the eternity of the third kind of knowledge causes eternal love. If we consider E5p33, which aims to demonstrate the eternity of this intellectual love, we see that, because the third kind of knowledge is eternal, ‘the love that arises from it must also be eternal’ (Eth, V, 33: 611/G, II, 300). However, the demonstration’s internal references are of significant importance: they reaffirm that it is firmly rooted in the mind alone. By referring back to E5p31, Spinoza demonstrates the eternity of this love through the third kind of knowledge, which depends on the mind as its formal or adequate cause (as the mind is itself eternal) (Eth, V, 31: 610/G, II, 299). Therefore, the steps leading to the demonstration of the eternity of the amor Dei intellectualis are as follows: (1) our mind is eternal, (2) the third kind of knowledge is eternal,Footnote ⁴⁵ and (3) the love arising from it is eternal. We can thus see that the mind’s eternity is the formal cause on which the eternity of knowledge and love depend.