The Mind as Mode
Spinoza considers individual minds to be modes of the attribute thought, and thus modes of God or nature. Minds (like bodies) are “singular things” (D7), which is to say that they are finite existing modes that exist for some “indefinite” duration (D5) and then are no more.
What is perhaps (at least initially) startling about Spinoza’s position is that individual minds are modes of God’s mind. This means that they “express God’s nature in a certain and determinate way” (E2:P1D). Thus, your mind and mine are each expressions of God’s infinite intellect.
Spinoza’s Parallelism
Spinoza has a very unique way of being able to deal with problems regarding dualism and interaction. First, he thinks (and as naturally follows from his views in E1) that, since there is only one substance, the infinite variety of attributes that belong to it include both extension (i.e. body) and thought (i.e. mind). So there is just one substance that both thinks and is extended.
the thinking substance and the extended substance are one and the same substance, which is now comprehended under this attribute, now under that. So also a mode of extension and the idea of that mode are one and the same thing, but expressed in two ways. (E2:P7D1C, p. 119)
But Spinoza denies that modes of extension and of thought causally interact. As he puts it,
The modes of each attribute have God for their cause only insofar as he is considered under the attribute of which they are modes, and not insofar as he is considered under any other attribute. (E2:P6, p. 118)
So modes are caused and conceived of only through the attribute of which they are modes, and not through any other. Thus, though a single substance (i.e. God) is the cause of all modes, the causal activity is always conceived of through the mode’s attribute and not through another. Spinoza thus elegantly avoids the problems raised by Descartes’s interactionism, while still maintaining a separation between (modes of) mind and (modes of) body.
One potential problem for this view, however, is that while it is true that each attribute exists necessarily and that none can exist without the others (because all are necessary), it is not true that an attribute exists in virtue of any other, so there is no connection between attributes that could unify those attributes together other than the (prior?) fact that a substance cannot share attributes. Indeed, it seems like Spinoza’s view here depends on his contention that substance is absolutely infinite, that attributes cannot be shared, that God has all attributes, and that each attribute is conceived in and through itself. Thus, there can be nothing more to the “unity” of the infinite plurality of attributes (or even just extension and thought) than the fact that they are all attributes of the one substance.
Spinoza’s parallelism consists in the fact that, though neither different attributes nor modes of different attributes causally interact, nevertheless the order of modes of one attribute mirrors the order of modes of another, or more specifically:
The order and connection of ideas is the same as the order and connection of things. (E2:P7, p. 119)
So the very same causal order of ideas through which God thinks of an existing circle maps the causal order of bodies through which that existing circle has come to be.
For example, a circle existing in Nature and the idea of the existing circle, which is also in God, are one and the same thing, which is explained through different attributes. Therefore, whether we conceive Nature under the attribute of extension, or under the attribute of thought, or under any other attribute, we shall find one and the same order, or one and the same connection of causes, that is, that the same things follow one another. (E2:P7S, 119)
The Mind & Its Body
The human being is not, as with Descartes’s view, a composite or “union” of two distinct substances. Instead
- Pll: The first thing which constitutes the actual being of a human Mind is nothing but the idea of a singular thing which actually exists.
- P13: The object of the idea constituting the human mind is the body, or a certain mode of extension which actually exists, and nothing else.
So an existing mind is constituted by a “singular idea”, which has as its object a specific existing body. And since, from E2:P7 we know that a mode of extension and a mode of thought are “one and the same thing expressed in two ways” there is a sense in which Spinoza can say that the mind and its body are identical. In this sense Spinoza even more radically departs from Descartes.
The fact that a mind has as its object a specific existing body also has ramifications for another important issue – the immortality of the soul. On Descartes’s view, because he identified the mind and soul, and because the soul is an independent being, it can exist independent of its (and perhaps any) body. Descartes thus takes his dualism to secure a basic religious tenet regarding the afterlife. Spinoza, in contrast, contends that there is a much stronger connection between a mind and its body – the mind is a particular body. So if the body’s existence is finite then so too is the mind.
The Mind & Eternity
However, Spinoza (much to many an interpreter’s perplexity) there is a sense in which aspects of the human mind (though not the human person) are “immortal”, at least in the sense of being eternal. In Bk 5 Spinoza says,
it is clear that our mind, insofar as it understands, is an eternal mode of thinking, which is determined by another eternal mode of thinking, and this again by another, and so on, to infinity; so that together, they all constitute God’s eternal and infinite intellect. (E5:P40S, p. 263)
Though it isn’t entirely clear here what Spinoza means, one possibility is that the various ideas in the human mind, insofar as they are “adequate” or constitute true ideas, are part of God’s eternal intellect. And Spinoza argues that God is “eternal” in two senses. In the first sense (call this the “sempiternal” sense), God exists at all times or always. But in another sense of “eternal” God exists in a manner that transcends time – i.e. God exists timelessly. Spinoza’s suggestion in Bk 5 is that this timeless existence also includes the modes of God, so that there is an “aspect of eternity” under which even mental modes or ideas exist. Spinoza thus seems to think that while no person can exist in a way that is either eternal nor sempiternal, nevertheless the ideas one enjoys during one’s existence have a timeless aspect or element to them, and in this sense only can an individual person partake of immortality.