«Introduction More than two-thirds of the Treatise on the Emendation of the Intellect is about truth. Spinoza explains why true ideas are preferable ...»
direct evidence is from TIE §§34–36. Here are the most important snippets:
[A] true idea of Peter is an objective essence of Peter [. . .] [T]o have the objective essences of things, or, what is the same, [true] ideas [. . .] [T]ruth itself, or the objective essences of things, or the ideas (all those signify the same) [. . .] Let’s build on the scholastic background introduced above. An objective existence of Peter is just an idea that represents his existence. Likewise, an objective essence of Peter is just an idea that represents his essence. Thus, when Spinoza says that true ideas are objective essences, he’s saying that true ideas represent essences. Other passages support this interpretation. He claims that ideas acquired from report or random experience do not allow us to “perceive any essence of a thing” and are therefore false (TIE §26; see also Ep. 10). Also, he says that a true idea must “agree completely with its formal essence” (TIE §42).
As an example of a true idea that represents a non-existing thing, he mentions an architect’s idea of a building that he might never build (TIE §69). Unlike, Truth in the Emendation 71 say, a businessman’s idea of the same building, the architect’s idea represents the building’s essence, because the architect’s idea represents how the building’s parts would be arranged and how it could be built (TIE §96). The architect’s idea can be true even if the building isn’t erected, because it is an idea of the building’s essence. Finally, Spinoza says that true ideas agree with what they represent (see AGREEMENT) and in the Emendation he uses conjugations of “agrees” [convenire] to describe only a relation between true ideas and essences (TIE §§41–42).
Thus, Spinoza accepts:
A true idea of x represents x’s essence.
From a contemporary point of view, ESSENCE has some surprising implications.
Consider the idea we might express with the sentence “Peter is 150 pounds.” Even if this idea correctly describes Peter, it’s false, because it doesn’t represent his essence. He’d still be Peter if he gained weight. Likewise, consider the idea we might express with “Peter exists.” Even if Peter actually exists, it’s false, because it doesn’t represent his essence. Peter can exist at some times even if he doesn’t exist at all times. In contrast, consider the idea we might express using “My mind is united to a body.” This is an idea of our own essence (TIE §22), and therefore might be true.
ESSENCE is part of a long tradition of linking truth and essence, a tradition
that stretches as far back as Plato.8 Here is Descartes’ variant, repeated verbatim in Spinoza’s reconstruction of the Principles (see DPP1d9 | G I/150/37):
When we say that something is contained in the nature or concept of a thing that is the same as if we said that it is true of that thing [...].
(Descartes, Second Replies, CSM II 114 | AT VII 162) Likewise, Descartes’ meditator is unsure if he has a true idea of coldness because he’s unsure if coldness has an essence (Meditation Three, CSM II 30 | AT VII 44). According to both Descartes and Spinoza, it is definitive of a true idea of x that it is an idea of x’s essence.
There’s a reason that philosophers in this tradition link together truth and essence. In their tradition, “true” has an evaluative dimension. If you have a true idea of your body, you have the best idea of your body, and that’s an idea of its essence (see, e.g., E2p43s). Sensory ideas are always false, not because they always misrepresent external bodies, but because they don’t give us the best kind of understanding of those bodies—they don’t represent their essences.9 See Plato, Republic, 6.508d and 6.513b for two influential passages. It’s debatable whether philosophers in this tradition correctly interpreted Plato.
Importantly, to say that Spinoza’s notion of truth is continuous with the Platonic tradi
says that a true idea of x must represent x’s essence. It doesn’t say
ESSENCEthat this is all that a true idea of x can represent. According to Spinoza, a true idea of x can also represent x’s properties [propria], which for Spinoza are the features of x that follow from its essence. This additional feature of true ideas is evident in many passages. To start, he says we can’t understand the properties of things until we understand their essences (TIE §27). This suggests that we can understand the properties of things after we understand their essences, presumably by deducing those properties. For example, he says the essence of a circle is that it was constructed by holding one end of a line in place while rotating the other end (TIE §96). He says that we can understand, that is, form true ideas about, a circle’s properties by deducing them from this essence, including the property of having points equidistant from the center (TIE §§95–97).
For a more dramatic example, consider God’s true idea of his own essence.
This idea can represent Peter’s weight and existence, because Peter’s weight and existence follow from God’s essence, and therefore are properties of God, and God’s intellect is powerful enough to infer these consequences (TIE §§54, 99, E1p16). Other passages further corroborate this interpretation (e.g. TIE §95, 107, 108; see also E1p16, E2p40s2).10 Thus, through deduction, an idea of x’s essence can also represent x’s properties. From a contemporary point of view, this might seem odd, because when someone deduces a conclusion from a premise, we usually say she’s transitioning from one mental state to another. We talk in this way because we individuate Augustine, and Anselm, many in this tradition claim that something is true to the extent that it exists. These philosophers describe God, bodies, and actions as more or less true. Plato says that philosophers are “lovers of true being” (Republic, 6). The author of the Gospel of John says that “I am the way and the truth and the life” (14:6). Augustine says that “the truth is that which is” (Soliloquies, II, 5). Anselm says that “whatever is, is truly” (On Truth, 4, 5, and 7). Like Descartes, Spinoza just describes ideas as true.
Spinoza’s favorite example involves proportions (TIE §23–24, E2p40s2). While this example isn’t straightforward, it nonetheless further confirms the link between true ideas and essences.
Spinoza says there are two ways we can know that n = 6 in the missing proportion 2/4 = 3/n. First, we can know n = 6 in virtue of knowing the essence of proportions in general. In particular, from the essence of proportions in general we can deduce a property of all proportions, namely that if then xm = yn (see Euclid, Elements, Book VII, Proposition 19.) We can then deduce that if 2/4 = 3/n then n = 6. Thus, through deduction, our idea of the essence of proportions in general can include knowledge that n = 6, just as, through deduction, our idea of a circle’s essence can include knowledge of all its properties. Second, we can know n = 6 in virtue of knowing the essence of 2/4 = 3/n. From that essence we can immediately deduce that n = 6. Thus, our idea of the essence of 2/2 = 3/n can include knowledge that n = 6. We don’t need to deduce n = 6 from a property shared by all proportions. We can know it “intuitively, without going through any procedure” (TIE §24).
See Garrett, “Spinoza’s Theory of Scientia Intuitiva,” 106–109, for helpful analysis of these two different ways of knowing that n = 6.
Regardless of how we know n = 6, that knowledge is included in an idea representing an essence, whether it’s the essence of proportions in general, or the essence of 2/4 = 3/n in particular. This reinforces the link between true ideas and essences.
Truth in the Emendation 73 mental states by their representational content, and conclusions usually have representational contents that differ from the premises. We also talk in this way because we think of deduction as a psychological process that takes us from one mental state to another. But Spinoza conceives of ideas and deductions differently. As he conceives of them, deduction allows the same idea to represent both premises and conclusions, which is why the same idea can represent both a thing’s essence and its properties.
In light of the following, we can clarify ESSENCE:
A true idea of x represents x’s essence and perhaps also x’s properties.
ESSENCE might be too weak. When Spinoza writes that, “[A] true idea of Peter is an objective essence of Peter [. . .]” I take him to be giving a partial definition; it is definitive of a true idea of Peter that it is an idea that represents his essence.
He’s not just listing another feature of that idea. Nonetheless, let’s not build this into essence, just to be cautious.
ESSENCE might be too weak in another respect. There’s evidence that a true idea of x can’t represent anything besides x’s essence and properties. Consider again an idea of a circle’s essence. It can’t also represent the number of circles existing in reality (TIE §108, E1p8s2), or a circle as moving (TIE §72), because these facts don’t follow from the essence of the circle. These passages suggest that a true idea of the circle can represent only the circle’s essence and properties.
4. Suppose you have a true idea of God as existing; that is, you truly believe that God exists. What, if anything, can you do to become certain that God exists?
Descartes says that you can become certain that God exists by attending to the clarity and distinctness of your idea. In particular, you can use the clarity and distinctness of your idea as a sign of its truth, and by attending to that sign, you can become certain (see, e.g., Meditation Three, CSM II 2:25 | AT VII 36).
Spinoza rejects this explanation. He insists that we don’t need another feature
of an idea to indicate its truth. He writes:
For the certainty of the truth, no other sign is needed than having a true idea. (TIE §35) He later reformulates this as the claim that [T]ruth makes itself manifest. (TIE §44)
to this interpretation: if S has a true idea that x is F, then S is certain that x is F.11 But that’s at odds with the text, because Spinoza says we can doubt that x is F even if we have a true idea that x is F (TIE §§50, 79). For example, we can doubt that the soul is unextended even if we have a true idea of the soul, because we can fail to distinguish our true idea of the soul from our false, sensory ideas of the soul (TIE §74). Thus, it’s not enough to merely have a true idea of the soul.
At a minimum, we have to distinguish that idea from our other ideas of the soul.
Garrett proposes a better interpretation. According to his interpretation, we don’t need another sign of truth, because we can attend directly to the features in virtue of which an idea is true.12 This interpretation explains why we’re sometimes uncertain despite having a true idea. It also explains why we don’t need to attend
to the clarity and distinctness of an idea to become certain. Let’s give this a title:
CERTAINTYIf S has a true idea that x is F, then S can become certain that x is F by becoming aware of the features in virtue of which that idea is true.
Two terminological clarifications are needed: first, what is the meaning of “S can”? Because Spinoza insists that we can achieve certainty if we follow his method (TIE §35), the phrase “S can” in the antecedent should be understood to mean something like “it’s within S’s actual power to.” Second, what does Spinoza mean by “certain”? He says that doubt is the suspension of affirmation (TIE §78). Presumably, then, certainty is complete affirmation.