Spinoza on Having a False Idea
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- Lewis, D. Int Ontology Metaphysics (2007) 8: 17. doi:10.1007/s12133-007-0002-y
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Naturalism pervades Spinoza’s doctrines of The Ethics, but the contours of it often bewilder us. In this light, I consider the account of falsity, or having a false idea, as presented by Spinoza in Proposition thirty_five of the Second Part, its demonstration, and the subsequent note. Based on my interpretation I argue for the claim that his account has coherence and makes sense. Further, I examine the significance of what Spinoza says about falsity for comprehension of his philosophy overall, especially as regards its contrasts with the philosophy of Descartes.
Benedict de Spinoza’s assertions about truth and falsehood in the Second Part of The Ethics may prove troubling to Spinoza interpreters. Is it sensible to hold, as Spinoza does, that a true idea is the standard of truth? That position seems problematically circular and seems to render the determination of truth arbitrary and whimsical. Also, can one say that falsehood is merely the absence-of-knowledge characteristic of inadequate ideas, ideas, that is, that lack the marks of truth? Failure to perceive the falsity of one’s false ideas does not seem, as Spinoza’s analysis suggests it is, a sufficient explanation for the phenomenon of false belief.1
Nevertheless, I maintain that Spinoza has a coherent and sensible stance on the matters of truth and falsehood. Here I will argue for my case concerning his theory of falsehood, leaving full discussion of the standard of truth for another occasion. To make my argument, I need to sort through intricacies of his distinctive one-substance ontology, since that ontology provides the setting for his theory.2 In the Second Part of The Ethics Spinoza constructs an explanation for the occurrence of perception, or consciousness, in the experience of human and other individuals. He constructs it from his propositions (1) about the inherent and limitless existence of the sole substance and (2) about the sole substance’s law of nature-thereby explaining perception without invoking a divine intention or purpose, or even supposing such an intention’s existence. His position contradicts that of Descartes, for example, who accords to the fact of our consciousness, or thought, the significance of likening us to the Divine and of distinguishing us from animals and other material things, while giving our bodies no comparable metaphysical roles. Spinoza’s account of truth and falsehood coheres, I will argue, with his naturalistic explication of perceptions and ideas; and it aims at illuminating, as Spinoza sees it, such errors as the error of Descartes. Understanding Spinoza’s account should, then, help us to comprehend his philosophic position overall.
In order to orient my discussion, let me present his definition of truth along with an example of a true idea and of a false idea. Spinoza gives his definition in an axiom of the First Part, where he says: “[a] true idea must agree with its object” (IA6).3 This definition calls for clarification. Thus, he asserts in his definition of idea, in the Second Part, that an idea is “a concept of the mind which the mind forms because it is a thinking thing” (IID3). He emphasizes the activity of thought, explaining that “I say concept [in defining ‘idea’] rather than perception, because the word perception seems to indicate that the mind is acted on by the object. But concept seems to express an action of the mind” (IID3Exp.). In contrast, by his notion of the object-of-an-idea Spinoza intends that thing or circumstance, or whatever, concerning which we have the idea (whether or not we identify the object correctly).4 So an idea is an act of thinking, or a judgment, that so and so; an idea’s object is that actuality concerning which we have the thought, or judgment. The agreement lies, then, in the match between the idea vis-à-vis its content and the object vis-à-vis its occurrence: an idea agrees with its object and is thus true when the object is as the idea represents it. What should we say, though, about the word ‘must’ in the definition? I treat it as an intensifier, introduced to indicate the necessity-of-agreement required for an idea to be true-if the agreement fails, the idea is not true. I do not interpret the ‘must’ as a qualifier of ‘agree’, as if a special, mysterious kind of agreement called “necessary agreement” has to hold between a true idea and its object.
Still, my presentation needs the amplification of two further points. First of all, objects are for Spinoza related to each other in complex webs of causal and conceptual relations, so that an idea will agree with its object only if it includes a representation of these relations. Consequently, an individual may make a true statement about something even though the individual does not have a true idea of it. For example, in the second note following Proposition forty of the Second Part, Spinoza illustrates his three levels of knowledge-imagination, reason, and intuition-with a single example: the problem of identifying the fourth number which has to a third the same ratio as a second number has to a first. All thinkers can, regardless of the level of knowledge, solve the problem in simple cases-i.e., can say truly what the number is. But the individual whose level of knowledge is that of imagination does not have a true idea of the proportion: such an individual relies on a teacher or on trials and, in doing so, does not grasp the relations that the solution has to the system of proportionality.5
A second aspect of the agreement of an idea with its object highlights an otherwise unnoticeable, but crucial, dimension of Spinoza’s conception of truth. In his ontology (to be discussed below) an infinite intellect has in every detail-and, in the ontology, there is an infinite intellect-an idea of each and every thing or event or happening, and so on: an infinite intellect encompasses everything, including itself, within the purview of its thought. In consequence, the object of an idea has, among its other relations, a relation to the idea which the infinite intellect has of it. So an idea will agree with its object only if it involves a representation of this relation. But the representation in this case, unlike in that of the others, affects not only the idea’s content but also its very being (esse formale or formal being, in Spinoza’s terminology): an idea’s character serves as evidence of an idea’s truth (or falsehood). Thus, an idea which I have will agree with its object and, so, will be true only if it itself bears to the object the relation the infinite intellect bears to it. Indeed, my idea and the infinite intellect’s idea are the same idea in the paradigmatic instances of a true idea.
Evidently truth and falsehood are not binary concepts in Spinoza’s usage. Agreement of an idea with its object constitutes both a sufficient and a necessary condition for the truth of an idea. Yet, in cases where the absolute agreement I identified above fails, an idea does not necessarily lapse into falsehood but may still, although with qualification, agree with its object. There are two possibilities: (a) the full agreement fails, but the idea does not mistakenly ascribe qualities to the object which the object does not have; (b) the agreement fails because the idea ascribes qualities to the object which the object does not have. False ideas fall under b, for in those instances an idea disagrees with its object, misrepresenting it. In the instances of a we might say that an idea exhibits nothing but the truth, although it does not exhibit the whole truth. In what follows, I include among true ideas ideas which are true in this non-exemplary sense expressed by a.6
From the style of The Ethics I am urged to suppose that I might adduce, as being a true idea, any proposition that Spinoza demonstrates. For he evidently believes that reality is as his propositions say it is or as the ideas expressed by his propositions represent it to be. Yet, such an example would be unhelpful, since, for one thing, it is often unclear what precisely his propositions say or what ideas exactly they express. All the same, in notes of the Second Part, he makes remarks about the sun and about our beliefs regarding it; and those remarks provide examples with which to elucidate his definition.
While commenting on error in his note following Proposition thirty-five, Spinoza remarks that, as he puts it, the “true distance” of the sun from us is “more than six hundred diameters of the earth.” Yet, he also remarks that, if we lack that astronomical knowledge and are ignorant of the way our body responds to the sun at such a distance, then we will, when the sun affects our body, make the error of thinking the sun to be “about two hundred feet away” (IIP35Schol.).7 So our idea of the sun as distant from us by more than six hundred diameters of the earth is a true idea. This idea agrees with its object; for the object, the sun’s actual distance from us, is faithfully represented by the idea. On the other hand, the reason why the idea of the sun as about two hundred feet away is a false idea is that the sun lies, in fact, much farther from us than that idea indicates. These examples will supply guidance for the examination below.
Falsity consists in the privation of knowledge which inadequate, or mutilated and confused, ideas involve. IIP35
There is nothing positive in ideas which constitutes the form of falsity (by P33); but falsity cannot consist in an absolute privation (for it is minds, not bodies, which are said to err, or be deceived), nor also in absolute ignorance. For to be ignorant and to err are different. So it consists in the privation of knowledge which inadequate knowledge of things, or inadequate and confused ideas, involve, q.e.d.
I will analyze his position and will defend what he has to say, beginning with remarks on the proposition and then a commentary on the demonstration.
Privation is absence or lack; when we have an inadequate idea we do indeed have an idea, but we lack something else that we need in order to form an adequate one: namely, we lack some further knowledge or some supplementary idea. The idea we have is partial and disordered (“mutilated and confused”), one representing its object in an incomplete and jumbled fashion. Additionally, an inadequate idea does not display, but rather masks, its own partialness and disorder. So the absent knowledge involved in having inadequate ideas has to reveal the inadequacy of the inadequate idea and, in ideal cases, has to supply the order and completeness required for an adequate one. We give up our false idea or false belief along with the discovery of that knowledge.
To demonstrate his proposition Spinoza considers four possibilities for explaining falsity; he provides reasons for rejecting three of them and accepts, in consequence, the fourth. The four he considers are (1) falsity is something positive in ideas; (2) falsity is absolute privation; (3) falsity is absolute ignorance; and (4) falsity is the privation of knowledge involved in inadequate ideas.8 These accounts vary widely, with the presence-of-something-account serving as one extreme and the absence-of-everything-account serving as the other; the absence-of-something-possibilities are the two intermediaries. Concerning absolute privation, Spinoza says that this view fails for the reason that “it is minds, not bodies, which are said to err, or be deceived.” I interpret his point to be that the concept of having a false idea presupposes the concept of thought; and since bodies do not have thought as a possibility at all, bodies can no more make a mistake than they can get things right. Yet, bodies would err if falsity consisted of absolute privation. In contrast to bodies, thinking individuals who are ignorant can err; but Spinoza rejects the ignorance-account because ignorance and error are different phenomena. A thinking individual who is ignorant of a matter has no opinion about it and so, not surprisingly, has no false opinion. Furthermore, he rejects the account of falsity framed in terms of something positive, referring us to Proposition thirty-three and to its demonstration, where he defends claims about the one and only substance and about what can and cannot be present in substance.9 Thus, we need to delve into the ontology in order to comprehend his reasoning-a task to which I now turn.
I will be sparing in my discussion of Spinoza’s views, noting only those features of his position that are relevant to the rejection of the something-positive explanation. Near the beginning of the Second Part Spinoza introduces and defends as an indisputable fact the existence of the idea Dei, or idea of God. Bearing a dual reference, the term ‘idea Dei’ refers, on the one hand, to an idea, a highly complex idea, the object of which is God, or substance, and all the things which necessarily follow from substance. The idea represents and, as Spinoza argues, faithfully represents everything-all that does not exist as well as all that does. Yet, besides being the object of this idea, substance is, on the other hand, also the thinker, the infinite intellect or infinite thinking being, whose idea this idea is.10 Still, as Spinoza aims to demonstrate in Proposition two, substance is not only a thinking thing but is also an extended, or bodily, thing. So, the idea Dei is at once both (1) an idea that has as its object substance and all the manifestations of substance and (2) an idea that is had by substance, namely, a highly complex idea composed of a great many ideas, all of which are adequate and true.
In introducing the idea Dei, Spinoza emphasizes the causal relationships connecting the idea with its object, specific attention to which furthers our understanding. Thus, the object of the idea, namely, substance, causes the idea, making the idea an effect of its object; but the object, namely substance, causes the idea only to the extent that substance is a thinking thing. Insofar as substance is an extended thing, substance does not cause the idea, and the idea does not cause the extension, or the material dimensions, of substance. In that respect, the idea and its object are neither cause nor effect of each other but are coordinate expressions of the reality of the one substance.11
So where does this scheme put us? On Spinoza’s position, human beings are finite and determinate individuals who think and have bodies; we are, as such, modes of substance. Though limited and, moreover, liable to confusion because of our common ignorance of the nature of mind, we can still form an idea of an infinite intellect and, within limits, of the ideas that an infinite intellect has. Indeed, Spinoza exploits our capacity to conceive of an infinite intellect to construct an argument for the very existence of such an intellect (see IIP1Schol.). There is and can be for Spinoza only one such intellect, and that intellect encompasses all ideas and, for this reason, all of our ideas. So insofar as I have an adequate idea of an object, the infinite intellect has an adequate idea of that object. But insofar as I have an inadequate idea, the infinite intellect has, even so, an adequate idea, an idea which incorporates and, together with further ideas, completes my partial idea and dispels the disorder of my confused and erroneous thinking. Spinoza encourages us to form our ideas, as he puts it, “internally” (IIP29Schol.) and “according to the order of the intellect” (IIP18Schol.) and to avoid the inadequate understanding involved in “perceiv[ing] things from the common order of Nature” (IIP29Schol.).
I can now complete my presentation of Spinoza’s account of having a false idea. As we have seen, Spinoza introduces his position with the assertion that there is in ideas nothing positive which constitutes the form of falsity. Drawing on his views of substance, he demonstrates this premise by reducing its contradictory to absurdity. Suppose that in ideas there is something positive which constitutes the form of falsity-is something other than partialness and absence, that is to say, which causes thinkers to have false ideas. On this supposition, the infinite intellect has an idea, indeed a true idea, the object of which is this something. But since by hypothesis the something is the cause of false ideas, it then causes the infinite intellect to have false ideas-an absurdity, because all the ideas that the infinite intellect has are true.12 As a determined critic of alternatives, Spinoza concludes that his own proposition about falsity in terms of the privation of knowledge which inadequate ideas involve explains fully the phenomenon of false ideas or beliefs. In contrast with the something-positive-account, an account in terms of privation of knowledge confines false ideas to the thinkers who suffer from privation of knowledge.
Well, then, what should we say about Spinoza’s theory of falsehood? To contemporary sensibilities, the alternative of recurring to an infinite intellect to clarify the everyday occurrence of false ideas seems contrived and archaic. Nowadays, the notion of an infinite intellect plays no role in philosophy; we do not provide explanations by recourse to such terms. Indeed, talk about an infinite intellect strikes us as ontologically suspect and metaphysically spooky. Still, if we view Spinoza’s philosophy with historical perspective, we can see that his position is basically a reasoned assertion of metaphysical and epistemological realism: reality has a certain definite-order and definite-structure, and we are capable of discovering what that order is, at least in outline. Many contemporary philosophers affirm metaphysical and epistemological realism, but oftentimes they do so stridently and without argument. Spinoza has, if nothing else, the advantage of advancing an argument.
Even so, we do not need to embrace the reality of an infinite intellect to appreciate the strength of his account of our having false ideas. Let us simply accept the infinite intellect as an envisaged ideal. His account of falsity still has force, as attention to its role in the example about the sun can help to bring out.
4 The sun
Likewise [as in the example above], when we look at the sun, we imagine it to be about two hundred feet distant from us, an error which does not consist only in this act of imagination but also in the fact that, while we imagine it in this way, we are ignorant of the true distance of the sun and of the cause of this act of imagination. For even if afterwards we come to know that the sun is more than six hundred diameters of the earth distant from us, we nevertheless continue to imagine it so near; indeed, we imagine the sun so near, not because we are ignorant of its true distance, but because an affection of our body involves the essence of the sun, to the extent that the body is affected by the sun. IIP35S13
To imagine is, for Spinoza, to perceive or experience, and it involves an idea the object of which is the perceived or experienced thing; in imagining we perceive an affection of our body, and we form an idea of our body and of external bodies in their varying affection-causing interactions. The object imagined is not necessarily imaginary; nor does the idea of the imagined object necessarily misrepresent its object, although, when it does, it masks its own falsity and inadequacy. To reveal the inadequacy of an inadequate idea requires an idea that is not a part of an act of imagination. Spinoza’s point, adduced by means of the illustration, aims to bring out the fact that an idea involved in imagination is not inherently false but is false-when it is so-because of the surroundings of the idea.
In the example he considers a thinker who, while ignorant of the sun’s actual location and of the effect of the interaction between our body and external bodies like the sun, perceives or experiences the sun as near and erroneously judges the sun to be near. This individual’s act of imagination involves both a perception of, and an idea of, the sun as about two hundred feet distant from us. Spinoza asks whether the act of imagination on its own explains the thinker’s error; and answers, No. For consider an individual who knows the sun’s true distance and the response of our body to the sun. Even though that individual knows the sun’s true distance, that individual has the same perception of the sun’s nearness as does the confused thinker. So the act of imagination cannot alone be the cause of the judgmental error, which has been dispelled.
Spinoza then turns to the question of what causes our imagining the sun as so near, replying that our body’s response to the sun and the sun’s influence on our body produces what he calls an affection of the body; then owing to substance, which, as a thinking thing, has an idea of everything happening in the body, we perceive the affection and fashion an idea of (in other words imagine) the sun.14 So the positive element-our experiencing the sun as so near, along with our interest in knowledge-does not generate the falsity. Indeed, the confused thinker has, in imagining the sun to be so near, a bit of knowledge about the sun: the sun at its actual distance from us and with its influence on our body does look near. In short, the thinker’s false idea consists of a combination of elements not present in an infinite intellect; in particular, it consists of an absence of knowledge plus the presence both of a perception and of an inadequate idea. In the context of perceiving the sun, the idea that the sun is about two hundred feet distant from us originates from the thought’s fragmentation. But with the acquisition of relevant missing knowledge, the thinker gets the ability to grasp the error and, as a result, abandons the mistaken thinking.15
Someone might raise an objection to the account at this point, asking why an individual in the context of the ignorance which Spinoza describes doesn’t simply avoid error by forming only the idea of the sun as appearing to be near. Spinoza’s analysis of having false ideas seems to collapse in face of this possibility, because the possibility proposes an instance of the ignorance without the attendant error. Spinoza has a response, however.16 The distinction between seeming to be near and being near can supply no foothold for the individual utterly without background information about the sun’s location and the influence of sun-like bodies on our body; the context for application of the distinction is missing. In the circumstance which Spinoza describes, the thinker cannot avoid error by means of that contrast, because the thinker lacks access to the use of the contrast.
I have presented and defended Spinoza’s account of having false ideas. From my examination I conclude that Spinoza has a coherent and sensible theory of the occurrence of false belief. Still, one might ask how his theory and my explication help to illuminate Descartes’ supposed error about consciousness. For we easily grasp both the physical knowledge and the means of its discovery that we need in order to dispel the error about the sun; but we have difficulty comprehending the analogous ideational knowledge, and the method of its acquisition, so as to reveal the inadequacy of Descartes’ inadequate idea about thought. Spinoza’s doctrine of substance supplies the response: we must form an idea of an infinite intellect and, within limits, of the ideas that an infinite intellect has. We can then draw on the concept of substance as a thinking thing in order to specify ideas as a domain of study and to investigate the order of causes as it displays itself in ideas. Spinoza’s account of having a false idea is such a study. When with this knowledge we perceive our own thoughts, we place our perception in the larger context of other thoughts and ideas, and we do not ascribe any special metaphysical significance to thought: ideas are things-among-things; and they have the same order and connection as things in general. Descartes lacked that knowledge; and so, he filled the absence with his fanciful view.
For an interpretation of Spinoza’s position on false belief markedly at odds with the interpretation I give below, see Jonathan Bennett’s A Study of Spinoza’s Ethics (Hackett Publishing Company, 1984), especially pages 153-184. In the respects I note above as well as in others, Bennett is led to find fault with Spinoza’s account, a good reason perhaps to entertain a fresh view of it.
I am referring to the ontology of ‘substance as absolutely infinite’, or of ‘substance consisting of an infinity of attributes’. Spinoza uses the word ‘God’ for this substance and, at various places in The Ethics, the word ‘Nature’. Remarking on the word ‘God’ in the note following Proposition forty-seven of the Second Part, he says that people often do not rightly apply names to things, and he offers his analysis of absolutely infinite substance as clarification of the object, or being, to which the term rightly applies. In my discussion I will confine myself to using the word ‘substance’ for absolutely infinite substance.
Benedict de Spinoza, The Ethics, First Part, Axiom six. I use (unless otherwise noted) Edwin Curley’s translation in A Spinoza Reader, edited and translated by Edwin Curley (Princeton University Press, 1994), and I follow the abbreviations and conventions that he lists on page xxxv.
This point introduces a considerable complexity into the discussion. For, according to Spinoza, we cannot straightforwardly identify the object of an idea with the referent of the subject term of the sentence we use to express the idea, even when we use words correctly. Thought is not self- disclosing or incorrigible, according to him; I may think I am thinking one thing when actually I am thinking something else. This problem of thought occurs on Spinoza’s analysis because that which the human mind is-its nature-is not evident to the mind; our mind does not possess an adequate idea of itself. To resolve this problem, we need a perspective which transcends the limits of mind, a perspective Spinoza seeks to advance in The Ethics.
See IIP41, where Spinoza assigns true and adequate ideas to knowledge of the second and third kinds and assigns false and inadequate ideas to knowledge of the first kind.
Spinoza seems plainly to refer to true ideas in the paradigmatic sense when he says in IIP43: “[h]e who has a true idea at the same time knows that he has a true idea, and cannot doubt of the truth of the thing.” He bases his convictions about true ideas and the standard of truth on this proposition. Yet, it also seems plain that true ideas in the non-paradigmatic sense cannot of themselves function as a standard of truth. A full discussion of these matters would require an investigation into the demonstration of Proposition forty-three along with an investigation of the details of the claims in the subsequent note. Such a discussion goes beyond the scope of this paper.
As regards my discussion, below, about the sun, I should note that Spinoza calls the responses of our body to external bodies, and the influence of external bodies on our body, “affections of the body.” Concerning affections, he distinguishes between (a) those which are effects of qualities that our body and external bodies have in common and (b) those which are effects of qualities with respect to which our body and external bodies differ. Furthermore, he identifies the former affections as those the ideas of the causes of which are “common notions,” the basis of corporeal science (IIP37 – 39); and he specifies the latter affections, which he labels “images” (IIP17 Cor. Schol.), as those of which we have perception or experience.
One might find Spinoza’s list of alternatives strange for the reason that it does not include the well-known account of falsity given by Descartes, who explains falsity in terms of a distinction between the infinitude of the freedom of our will and the finitude of our understanding. Spinoza does, though, take up Descartes’ view near the end of the Second Part, where he labels it a fantasy because it invokes what is actually a fiction, namely, a will lying outside the order of cause and effect. Spinoza needs to elaborate his own explanation before he can make this criticism. Yet, after considering the Spinozistic account, one might think that Spinoza himself has simply substituted one fiction for another, a criticism I address briefly below.
IIP33 reads: “There is nothing positive in ideas on account of which they are called false.” The demonstration appeals to IIP32, which states: “All ideas, insofar as they are related to God, are true.” Perhaps one might express the sense of Proposition thirty-two more clearly by translating Spinoza’s ‘referuntur’-which term Curley renders as ‘are related to’-as ‘are referred to’.
One might contest my use of ‘infinite intellect’ to refer to substance as a thinking thing. For Spinoza introduces in IP29Scholium and the two subsequent propositions a distinction between Natura naturans (nature naturing, substance absolutely infinite or substance consisting of an infinity of attributes) and Natura naturata (nature natured, the modes or affections of substance); and in this context he ascribes the intellect, whether finite or infinite, to Natura naturata and not to Natura naturans. That ascription makes the term ‘infinite intellect’ an alternative expression for the idea Dei, one of the infinite modes of substance. All the same, he includes in the initial definitions of the First Part a reference to an intellect (presumably an infinite intellect) in his definition of ‘attribute’ (ID4), and he defines ‘God’ or ‘absolutely infinite substance’ in terms of attributes (ID6). These definitions make an intellect a part of absolutely infinite substance. On the whole, I treat the opening definitions as primary and the later distinction as serving Spinoza’s polemic against the pervasive and inveterate anthropomorphizing of God.
See IIP5, IIP6, and IIP6C for Spinoza’s discussion of these relationships.
I propose this argument to fill in the reasoning of the demonstration for Proposition thirty-three. Some clarification may help. Let X be the something positive, B the false idea which X causes, and Y the object of which B is an idea. The infinite intellect has an idea A, a true idea, of object X. Since by hypothesis X exists, the infinite intellect must have not only the true idea A of object X but also the false idea B of object Y. The absurdity is the incoherence of the infinite intellect’s having false as well as true ideas: all ideas that the infinite intellect has are true ideas (Spinoza’s conception of an infinite intellect), and some ideas that the infinite intellect has are not true ideas (the hypothesis’ entailment).
My translation. Sic cum solem intuemur, eum ducentos circiter pedes a nobis distare imaginamur, qui error in hac sola imaginatione non consistit, sed in eo, quod dum ipsum sic imaginamur, veram ejus distantiam, & hujus imaginationis causam ignoramus. Nam tametsi postea cognoscamus, eundem ultra 600 terrae diametros a nobis distare, ipsum nihilominus prope adesse imaginabimur; non enim solem adeo propinquum imaginamur, propterea quod veram ejus distantiam ignoramus, sed propterea, quod affectio nostri corporis essentiam solis involvit, quatenus ipsum corpus ab eodem afficitur ( Spinoza, Opera, II, 117). Curley translates Spinoza’s distare in the first sentence with ‘as ... away’ rather than with ‘to be ... distant’ (I use the latter expression). And he translates prope adesse in the second sentence with ‘as near’ rather than with ‘so near’. Consequently, Curley’s rendering makes it difficult to distinguish the error (the idea or judgment ‘the sun is about 200 feet distant from us’) of the act of imagination, on the one hand, from the perception or experience (the appearance of the sun as something near) of the act of imagination accompanying the error, on the other.
Imagining the sun is a mode of thinking; an affection of our body which involves the essence of the sun is a mode of extension. Spinoza also calls such an affection an “image.” The affection or image does not cause the imagining, though; rather, the cause of the imagining is substance as a thinking thing, which has in itself an idea of everything that substance as a thing consisting of an infinity of attributes does.
If we should have become emotionally invested in the error, we will not abandon it without additional study, an activity the intricacies of which Spinoza examines starting with the Third Part of The Ethics.
See IIP17 and IIP49S(II/134), where Spinoza makes, in his own way, the point that I make immediately below in mine.