Descartes, R. (2000). Meditations on First Philosophy. Selections from Meditations 2 and 6. In R. Ariew and E. Watkins (Eds.), Readings in Modern Philosophy Volume 1: Descartes, Spinoza and Leibniz, pp. 30-32, 50. Indianapolis, Ind.: Hackett publishing. (Original work published in 1641).
Descartes’ method in the Meditations is known as Method of Doubt. The goal is to establish knowledge on a foundation of absolute certainty, rejecting any belief that can be even slightly doubted
Main sources of doubt = Skeptical arguments from sensory error
- senses = our senses sometimes mislead us (optical illusions, mirages, etc.) so sensory experience cannot be trusted as a foundation for certain knowledge
- dreams = dreams can feel completely real while we are in them and there is no clear way to tell if we are awake or dreaming, so it is possible that our current experiences are also illusions. This casts doubts on all knowledge based on perception
- How do I know that I’m not being tricked at every moment by a deceiving god or powerful spirit?
I think, therefore I am (Meditations 2)
Descartes tries to establish knowledge that is not undermined by any source of doubts, and he concludes that you cannot doubt your existence.
His thinking follows = the very process of doubting your existence involves a kind of reflection. In order to doubt, one must have doubtful thoughts and in order to have doubtful thoughts, one must exist.
“But what then am I? A thing that thinks. What is that? A thing that doubts, understands, affirms, denies, wills, refuses, and that also imagines and senses.”
From this conclusion, Descartes posits that the very existence of doubting proves that one exists but also that one exists as a thinking thing i.e. thought itself is identified as the essential defining characteristics of minds.
establishing bodies (Meditations 6)
Descartes believes that there is a passive faculty of sense perception that allows the receiving of sensory ideas, which requires an active faculty to produce those ideas.
He concludes that the active source cannot be himself (i.e. his mind) as he did not choose or control his sensation, and they often appear without his cooperation / against his will (pain, hunger, etc.). So, according to Descartes, there are two possible sources: (a) bodies i.e. material things. e.g. a tree causing the idea of a tree, (b) God who produces the sensory ideas in the mind directly without the need for actual physical things existing
Descartes argues that God would not deceive him by making him believe that his sensations comes from physical objects and there is also a strong natural inclination to think that sensory experiences comes from physical bodies. We also have no way of recognizing any “higher form” source for those ideas. Hence, bodies must exist.
Descartes’ distinction between imagination and pure intellect
Descartes uses the example of a chiliagon (a 1000-sided polygon) to illustrate this: one can intellect its definition (a polygon with 1000 sides) clearly, but can’t imagine all 1000 sides distinctly. He also notes that the image we imagine for a chiliagon would be the same as imagining a ten thousand sided polygon.
I am manifestly aware that I am in need of a peculiar sort of effort on the part of the mind in order to imagine, one that I do not employ in order to understand.
Descartes posits that pure intellection (understanding) is when the mind turn inwards towards itself to apprehend its own ideas, while imagination is when the mind turns to material things, picturing ideas that we could perceive by the senses or imagined by itself.
Descartes believes that imagination is not a necessary element of his mind and is if he did not possess imagination, he would still exist. So he concludes that imagination must be something conjoined with the body, and lends support to his mind-body dualism.
Descartes’ Dualism
By the end of the Meditations, Descartes believes to have proven the existence of minds and bodies where
- essence (defining characteristics) of minds = thought
- essence of material beings = spatial extension
Descartes’ argument for substance dualism (also known as Cartesian Dualism) on the Mind-Body-problem:
- I have a clear and distinct conception of myself as a thinking thing.
- I have a clear and distinct conception of my body as an extended thing.
- I can conceive of each of these things without conceiving of the other.
- “My ability clearly and distinctly to understand one thing without another suffices to make me certain that the one thing is different from the other, since they can be separated from each other, at least by God.” Therefore, “it is certain that I am really distinct from my body, and can exist without it.”
Descartes argues that mind and body are distinct substances as we can conceive of mind existing without body, and body existing without mind. And since w can conceive of the two things as separate without contradiction, then God could make them exist separately.
However, how are we sure that they are indeed independent. It is fully possible that while we conceive of them as independent, that doesn’t prove that they are independent in reality; there could be connections or dependencies we do not know of as our conceptions could be limited or incomplete. For e.g., modern science shows that mental activity depends on brain activity, suggesting a causal relationship between the two. Descartes seems to be drawing a conclusion about ontology from our conceptions of things that could be incomplete.
Ryle-concept-of-the-mind criticizes Descartes’ substance dualism calling it “the ghost in the machine.”
Descartes on the Problem-of-Mind-Body-interaction
How can entities with completely different natures enter into causal relationships with each other?
“There is nothing… nature teaches me more explicitly than that I have a body that is ill-disposed when I feel pain, that needs food and drink when I suffer hunger or thirst, and the like…. By means of these sensations of pain, hunger, thirst, and so on, nature teaches that I am present to my body not merely in the way a sailor is present in his ship, but that I am most tightly joined and, so to speak, commingled with it, so much so that I and the body constitute one single thing…. For clearly these sensations of thirst, hunger, pain, and so on are nothing but certain confused modes of thinking arising from the union and, as it were, commingling of the mind with the body.”
Descartes sees the unity of mind and bodies as a sort of solution to the Problem-of-Mind-Body-interaction. He treats the mind and body together as a composite thing, so much so that we can legitimately talk of them as being one thing.