Descartes’ Metaphysics: Understanding Substance, Thought, and Doubt
Descartes’ Metaphysical System
Key Concepts
Reason: The natural faculty of man, innate, a general instrument of knowledge. Also called common sense, it is equal in all men. Therefore, the diversity of opinion comes from how it is applied (method).
Formal Reality: The reality of the idea itself, i.e., being an act or subjective way of thinking. According to this reality, there is no difference between ideas.
Objective Reality: The content of an idea while it is a representation of a thing. It is capable of adopting various levels.
Res Cogitans: Thinking substance, spiritual, soul or self, whose essential attribute is thought. It does not depend on anyone or anything.
Wisdom: Universal science capable of improving the conditions of human life and leading to happiness. Descartes compares it to a tree because he conceives all knowledge as being a single science or method.
Ways: Passive faculties receiving ideas. They do not inform us about reality in itself, but their function is purely pragmatic.
Synthesis: The third rule of the method, which is to reconstruct the complexity from simplicity.
Substance: Descartes defines substance as that which does not need anything else to exist. However, of the three classes of substances he distinguishes (thinking, extensive, and divine), only the latter meets the conditions necessary to be considered as such. Nevertheless, Descartes maintained the concept to refer, in this case, to the *res cogitans* as a resource to demonstrate its independence from the material reality or *res extensa*.
Body: This term refers to Descartes’ extended substance, material that we perceive through the senses and whose existence he will seek to demonstrate rationally through the ideas that correspond to the thinking substance. Descartes thus establishes anthropological dualism, in which the material (body) and spiritual (soul) are independent.
Views: Knowledge not recognized as true prior to the course of methods and application of the method.
The Nature of Body and Soul
The text speaks of the nature of body and soul. It tells us that although we lack a body, we cannot say that we do not exist. It describes how from knowledge, one concludes that our essence lies in thinking, in “… just had ceased to think .. I came to know from this that was a substance whose essence or nature is not in thinking and that this substance to be no need of any place, nor depends on any material thing …” In that paragraph, Descartes attempts to explain that thought thinks about ideas and not things, that ideas are representations of things but these are never in thought. Also, of course, he describes doubt, very present throughout his work in “… doubt about the truth of other things …” where René doubts the veracity of practice, spirit, and everything around us.
Methodical Doubt
The text is based on Descartes’ metaphysical system, but to get to it, we must begin by studying the question. It is true that doubt is a prerequisite to thinking philosophically, but Cartesian doubt is so radical that it becomes methodical doubt, a method of philosophical thought.
Levels of Doubt
- First Level: The Fallacy of the Senses. At this level, the rationalist attitude doubts the testimony of the senses, but it certainly also makes us doubt the existence of our own body.
- Second Level: The Impossibility of Distinguishing Waking from Sleep. Doubt that things are as we perceive them in dreams. This makes the intellectual exercise to radical doubt as possible.
- Third Level: The Evil Genius. Conception of God as it comes from the omnipotence of free nominalism, which introduces total uncertainty.
Cartesian Deduction
Until Cartesian methodical doubt, thought was naively connected with reality. Thought thinks ideas and not things. Images are representations of things, but things are not in thought, as in the theory of abstraction. Descartes noticed that there can be no falsehood in ideas until they are attributed to some reality outside thought. The error can only come from making judgments, and will be avoided by preventing haste. Thought is prompted, in seeking security, by philosophical idealism: thought thinks about ideas, and external reality becomes a mystery.
The deduction of Cartesian metaphysics comes with René’s response to the observation of *cogito ergo sum*. Descartes replies that: “While I recognize the truth by my principles have always been known, no one has recognized them can be derived knowledge of all other things in the universe.” In finding an unquestionable truth, Descartes has found the ultimate ground or first reality from which deduction can begin.