MIND-BODY DUALISM One aspect of Descartes’ Meditations deals with the nature of the world we live in. Philosophical (metaphysical) theories that claim that the ultimate nature of the world is reducible to one single thing are called Monistic (adj. monism). Philosophical theories that claim that the nature of the world is reducible to two substances (things) are called Dualistic (adj. Dualism). Descartes is a Dualist as he divides the nature of the world into two unique substances which are not further reducible. These substances are often called “mind” and “body” and the form of Dualism that Descartes espouses is often called, “Mind-Body Dualism” The important thing to remember about Mind-Body Dualism is that these fundamental substances, “mind” and “body” are not different aspects of some single thing (like a frown is an aspect of a face, or ice, water, and steam are different aspects of the molecule H 2 O) but rather their fundamental nature is wholly different. What characterizes or defines one substance does not characterize or define the other. Mind is wholly different from Body.

“ Corporeal” things = “Bodies”: This is a general term, which is not to be understood as referring solely to human bodies - but rather any “thing” which is characterized by what Descartes calls “extended”. “Material object” or “Physical object” is another word often used synonymously with “bodies”-although these terms have other Philosophical meanings these days, the common meaning of “material object” or “physical object” gets us close to what Descartes means when he talks about corporeal things. “Corporeal” things are characterized by Extension: Extension means: occupying a unique position in space (height, width, breadth) and time. Speaking of extension, Descartes states, “I ascribe to these parts certain sizes, shapes, positions, and movements from place to place; to these movements I ascribe various durations” (Meditations VI) The uniqueness of this position means that bodies are able to act and be acted upon, in other words, since no two bodies can occupy the same space, if one body is moving (changing its location in space with respect to time) and ”hits” another body, then there is some type of interaction between the bodies. The first body is displaced, or the second body bounces off, or some combination of the two. (Think of billiard balls as examples of bodies, since they cannot occupy the same place, if one ball strikes another, some form of reaction or must occur) Certainly the world we live in is characterized by “bodies” - look around you, the fact that a pen can sit on top of a table (an not fall through) is evidence of the “occupying a unique position is space” property of bodies. When you stand up and place your feet on the floor, the fact that your feet cannot occupy the same place as the floor allows you to stand on top of the floor (or anything for that matter)- Of course some bodies have different properties, the rigidity of solid objects can be replaced by non-rigid substances, such as water or air, but even with non-rigid substances, your hand still displaces water or air when it moves through the same space.

MIND- This term is often used alongside other terms such as “mental”, “incorporeal”, “spirit”, “soul”, and so forth. According to Descartes, MIND is not reducible to BODY, or to physical or material objects. It is instead characterized by NOT occupying a unique position in space. How does one illustrate this? Look around you at some object in your immediate surroundings of the “bodily” type, like a chair, a table, a computer monitor, a pen, etc. Where is it located? One can answer this by providing some system of reference, “The chair is 5 feet from the front door” or even more specifically, ‘the chair is 5 feet along the north wall, and inward 3 feet to the east, and reaches a height of 2.5 feet from the floor’ (Some may recognize this as an attempt at a co-ordinate system, giving x,y,z co-ordinates to indicate the location of something. Indeed Rene Descartes is the father of what are called Cartesian co-ordinate systems, which are named after him!) NOW close your eyes and PICTURE in your mind the object you have just identified in your surroundings. Where is that MENTAL picture located? What is its length, width and breadth? NOTE: If your reply is that the mental picture is located in your head, and specifically in a region of your brain, then you are committed to a form of Monism, specifically that the mind is reducible to the physical (the brain, and its functions)

The Problem with Mind-Body Dualism: SO it seems that we have divided the world into two types of substances, Mind and Body. But a problem immediately arises when we think about this type of dualism. If the mental is in its essence different than the physical (body) then how do the two substances interact? Remember, what characterizes “bodies” -the material, or physical world - is their inability to occupy the same position in space. This allows my hand, for instance, to grasp a pen, and pick the pen up off the table. If all objects, hand, pen, and table could occupy the same space, then my fingers would go through the pen, and the pen itself could not lay on top of the table, since it would occupy the same space as the table. This is similar to the dilemma presented in the Hollywood movie Ghost - where the ghost of Patrick Swayze is unable to interact with the world around him. This leads to a problem however. If my mental world is related to my physical body then when I get up from the bed in the morning, why must my “mental” self be obliged to get up with me. When I will with my mind (command or think) “pick up a glass of water” how does the MENTAL thought MOVE or COMMAND my physical body to obey my thoughts? When I walk from one side of the room to the other, there is no reason to suppose that my MIND goes along with my body, since it need not obey the “pushing” of my body as it walks across the room. Notice, if they interact (push and pull) like physical bodies, then the distinction between the two is apparent, and not real, and the Philosophical position reduces to one of Monism (all is corporeal).

Questions to Ponder: 1. If mind and body are truly different substances, then how does the physical world affect the mental world? Or how do mental thoughts interact with our physical bodies? (Taking the movie Ghost as a hopefully familiar example: If Patrick Swayze’s ghost really can not interact with physical objects (his hand cannot grasp a door knob, for instance, then how is he able to stand on the floor or run up the stairs, since both standing on a floor and pushing your foot on the first steps of a stairway require the his “ghost” act against the floor and steps (well we need not expect philosophical consistency in a Hollywood movie, right?) But if we pursue this analogy even further, How does the Physical world interact with the Mental? When someone speaks, they create vibrations in the air that cause movement in the eardrum - but how are these sounds handed over to a mental world which is not characterized by interactions with the Physical world (In the Ghost analogy, how does Patrick Swayze’s ghost hear what is going on?) IF, we concede that Dualism is false, however, does this not also lead us to conclude that when the human body dies, nothing continues, not thoughts or wishes or memories, or any of our mental self?