Cartesian Dualism Notes

Are the Body and Mind Separate?

Cartesian Dualism is the idea explored.

The Body

• Each person has a body that they maintain through:
  • Keeping it healthy
  • Dieting
  • Lifting weights
• The body has spatial dimensions:
  • Height
  • Width

The Mind

• The mind is cultivated through:
  • Studying and learning
  • Traveling to have experiences
  • Watching movies to be entertained
• The mind does not seem to have:
  • Color
  • Shape
  • Size
• Beliefs are not "blue" or "square."

Consciousness

• Consciousness involves:
  • Awareness of sensing, feeling, and thinking.
  • When asleep or knocked out, consciousness is absent.
  • Upon waking, consciousness returns with sensations like feeling bedsheets and smelling breakfast.

Subjectivity of Consciousness

• Consciousness is subjective:
  • It exists only when experienced by someone.
  • Direct awareness of one's own consciousness is unique.
  • It has a "first-person" nature.

Mind vs. Body

• Mental properties seem completely different from the body.
• The mind and body do not appear to be the same kind of thing.

The Mind-Body Problem

• The difference between mind and body has created difficult philosophical problems.
• These problems have puzzled people for a long time.

Rejection of Dualism

• Some reject the idea that the mind and body are completely different.
• They argue that nothing exists other than the physical.
• Therefore, the conscious mind must be part of the physical body.

Acceptance of Dualism

• Others accept that the mind and body are different.

Descartes and Substance Dualism

• The idea that the mind and body are separate is ancient.
• Descartes was the first modern philosopher to provide clear arguments for this view.
• Descartes aimed to firmly ground truth using his method of doubt.
• He arrived at the certainty: "Cogito ergo sum" (I think, therefore I am).

Immaterial Mind

• Descartes concluded he has an immaterial mind distinct from the physical body.
• Human beings consist of two distinct things:
  • A material body
  • An immaterial mind

Substance Dualism Defined

• This view is called Substance Dualism:
  • "Dual" means 2.
  • "Substance" means the "stuff" on which things happen.

Interactionism

• Descartes believed in interactionism.

Interactionism Explained

• Interactionism is the two-way interaction between mind and body.
• Things that happen to the body affect the mind, and vice versa.
• Certain brain areas can cause sensations (e.g., itchiness, hunger) in the mind.
• The mind can be causally affected by the brain (and the brain by the mind).

Arguments for Substance Dualism

• Arguments are presented to support the belief in substance dualism.

The Conceivability Argument

• The Conceivability Argument:

  1. We can conceive of ourselves existing without a body.
  2. We cannot conceive of ourselves existing without a mind.
  3. If I can conceive of something, it is possible.
  4. So it is possible for my mind and body to be separate.
  5. So my mind and body are separate.

Elaboration of Premises

• P1: We can conceive of ourselves existing without a body.
  • Imagine floating around the room as a "ghost."
  • The ability to imagine this supports Descartes' point.
• P2: We cannot conceive of ourselves without a mind.
  • Cannot think of oneself without thinking or perceiving.
  • Thinking is necessary for the self.
  • Thinking is part of the essence of the self.
• P3: If I can conceive of something, it is possible.

Example of a Car

• Imagine a car.
• Imagine a car without wheels.
• Can you imagine a car without a shape?

Essential Parts of a Car

• You can imagine a car without wheels, but not without a shape.
• This shows that tires are not an essential part of a car, but shape is.
• Relates to Descartes' wax candle example.

Essence of Things

• The mind can grasp the essence of things through clear and distinct ideas.
• A car without tires is still a car, but a car without shape is not a car.
• Similarly, you can imagine yourself without a body.
• You cannot imagine yourself without a mind.
• Tires are not essential to a car, and your body is not essential to YOU.

Further Explanation

• P3: Ability to imagine a car without tires implies it's possible for a car to have no tires.
• P4: It is possible for the mind and body to be separate, like a car without tires.

Logic Summary

• Not having a mind is like a car with no shape (impossible).
• Not having a body is like a car not having tires (possible).

Conclusion

• P5: The mind and body are separate.
• You and your body are two distinct things.
• Tires are removable from a car, and the mind is removable from the body.

Car and Driver Analogy

• Analogy: A car and a driver.
• Cars and drivers are two different substances.
• The mind is like the driver, and the car is like the body.
• While a car might need tires, it doesn't necessarily need a driver.

Restatement of Conceivability Argument

• The Conceivability Argument:

  1. We can conceive of ourselves existing without a body.
  2. We cannot conceive of ourselves existing without a mind.
  3. If I can conceive of something, it is possible.
  4. So it is possible for my mind and body to be separate.
  5. So my mind and body are separate.

The Divisibility Argument

• The Divisibility Argument:

  1. My body is a divisible substance.
  2. My mind is an indivisible substance.
  3. Leibniz’s law of the indiscernibility of identicals
  4. Therefore, my mind and body are separate substances.

Elaboration of Premises

• P1: My body is a divisible substance.
  • The body can be cut and divided.
• P2: My mind is an indivisible substance.
  • The mind cannot be cut or divided.

Divisibility of Physical Bodies

• Physical bodies have parts.
• Even a hard diamond that can’t be cut can be divided into definable parts.

Example of a Diamond

• Imagine a magically hard diamond that can’t be cut.
• It can still have spatially definable halves.
• Otherwise, you couldn’t say it’s “half in or half out” of a box.

Indivisibility of the Mind

• Does it make sense to say the mind has parts?
• Is your feeling of pain in the top or bottom half of your mind?
• Do these questions even make sense?

Further Questions

• Is your belief that CocoIchi Curry is delicious in the right or left half of your mind?
• These questions don't make sense.

Leibniz’s Law

• P3: Leibniz’s law of the indiscernibility of identicals.

Leibniz’s Law Explained

• If two things, X and Y, are the same, then X and Y must have all their properties in common.
• If two things are the same, every part about them is the same.
• If there is some property X has that Y doesn’t, then X and Y are not the same thing.

Restatement of Divisibility Argument

• The Divisibility Argument:

  1. My body is a divisible substance.
  2. My mind is an indivisible substance.
  3. Leibniz’s law of the indiscernibility of identicals
  4. Therefore, my mind and body are separate substances.

Conclusion

• The body is divisible, but the mind is not.
• This means there is a difference between them.
• So they are not the same thing.

Discussion

• Review of the arguments in premise form.
• Judge the argument strength.