Cartesian Dualism Challenged
In this paper, I will examine the issues of individuation and identity in
Descartes’ philosophy of mind-body dualism. I will begin by addressing the
framework of Cartesian dualism. Then I will examine the problems of
individuation and identity as they relate to Descartes. Hopefully, after
explaining Descartes’ reasoning and subsequently offering my response, I can show
with some degree of confidence that the issues of individuation and identity
offer a challenge to the Cartesians’ premise of mind-body dualism.
Before diving into a critical examination of these two issues, it would be wise
to first discuss the basis of Descartes’ philosophy. Descartes begins his
discussion of mind by first disregarding everything that he can call into
doubt. After this mental cleansing, Descartes is left only with the maxim that
‘I cannot doubt that I am doubting.’ From this conclusion, Descartes states
that some entity must be doing this doubting, and claims that this entity is
his mind. The Cartesian mind has only one property: thinking. Consequently,
Descartes establishes a distinction between mind and body. The two share no
characteristics, as the body does not indulge in thinking, the mind’s solitary
function. Further, mind and body are independent of each other; mind can exist
even in the absence of body. At the same time, Descartes does not doubt that
“the mind begins to think as soon as it is implanted in the body of an infant.”
Yet the mind does not need the body to engage in introspection, the action of
thinking about thinking. Only introspection is immune from illusion, confusion,
or doubt. Information about the world outside of mind is prone to these
hazards. We cannot conclude with certainty that other minds exist. Thus, the
Cartesian is left to what I would dub a lonely existence: “Even if [a
Cartesian] prefers to believe that to other human bodies there are harnessed
minds not unlike his own, he cannot claim to be able to discover their
individual characteristics. Absolute solitude is on this showing the
ineluctable destiny of the soul. Only our bodies can meet.”
Now I will critically examine Descartes’ mind-body philosophy by addressing the
issues of individuation and identity. First, I need to be clear about the
issues I am addressing. In order to fully understand the problem of
individuation, we need to focus on what the word individuation itself means. We
can derive individuation from the Latin verb dîvîdo, meaning “I divide up” or
“I separate into parts,” and also the prefix in-, which in this case means
“into.” So, when we talk about individuation, we are talking about a state
wherein an object can be separated or isolated from other objects: I can
individuate Brown University sweatshirts from Rhode Island College sweatshirts
based upon my observation of the insignia on them. Specifically, I am concerned
with how I can distinguish minds from each other.
Strawson articulates the need for this distinction in his discussion of what he
labels “the central difficulty in Cartesianism.” Strawson argues that if we
want to talk about individual items—minds, bodies, computers, baseball cards,
bananas, or practically anything—we must first understand the difference
between one of that item and two of that item. In other words, to talk about an
individual, you have to be able to count the individual. However, Cartesian
philosophy does not allow for counting minds. The only mind you can know about
is your own. Through introspection, I may be able to conclude that I am a
thinking thing myself, much like Descartes did, but I cannot tell if the girl
sitting at the computer next to me has one mind, three minds, seventeen minds,
or even no mind at all. Thus the Cartesian cannot individuate minds. Strawson
finds this fact problematic for the Cartesians, as the Cartesian “wants his
doctrine to have the consequence that a perfectly ordinary man… has just one
soul or consciousness which lasts him throughout.” Anti-Cartesians like
Strawson have no such difficulty as they hold to the principle that one person
houses one mind: If I can count two people in a room, I can necessarily
conclude that two minds are present as well. When Descartes enters that same
room, he is unaware of how many other minds share his company. Already we can
see that the problem of individuation is a threat to the heart of Cartesian
dualism.
Next I will turn my focus to the issue of identity, which holds a similar
problem for Descartes. We can trace identity back to the Latin îdem, which
means “the same.” Consequently, my discussion of identity will involve the
problem of how I can determine that something is the same as itself. On the
surface, you might think that such an investigation is rather frivolous. But
consider the following problem: Am I the same person as the five-year old girl
who used to watch “Sesame Street” and “Mr. Rogers’ Neighborhood,” was afraid to
ride a bike without training wheels, and struggled with basic arithmetic?
Surely, I’m not literally the same little girl, but at the same time something
tells me that I am still the same Noelia today that I was then.
Strawson argues that, in addition to knowing how to count individual minds, we
must also have the ability to “know how to identify the same item at different
times.” The principle of identity is essential to guaranteeing that only one
mind is associated with only one body, the doctrine that Strawson says is
central to Cartesian dualism. Working under a Cartesian paradigm, you cannot
determine that minds are the same over time in the same way that we, as I
showed in my earlier example, consider bodies the same. Strawson argues that
even if a Cartesian claims to be directly experiencing his mind through introspection
and therefore has no need of explaining the identity of his mind, he still
cannot rule out the possibility that a thousand different minds may occupy him
during the next moment. As with individuation, Strawson and his fellow
anti-Cartesians can correctly identify minds in the same manner that I
identified myself as the same girl I was 9 years ago. Those operating under
Descartes’ philosophy cannot identify the same mind over time, and consequently
cannot speak “coherently” (as Strawson puts it) about mind.
Using Strawson’s analysis of Descartes as a guide, I have attempted to
demonstrate how two issues—individuation and identity—threaten to dismantle
Descartes’ philosophy of mind-body dualism. I have stood behind the
anti-Cartesian argument that in order to associate one mind with one body—which
Strawson claims is a vital principle to both Cartesians and anti-Cartesians—we
must think of mind as something dependent on a person and not as something
separate altogether, as Descartes would argue.