Cartesian Philosophy: Descartes’ Method and Ideas
Descartes’ Method
Descartes emphasized the need for a rigorous scientific method. He believed that a true science required a method that guided reason effectively. This method had three key features:
- Simplicity: It should be easy to understand and apply.
- Error Prevention: It should help prevent errors in reasoning.
- Knowledge Expansion: It should facilitate the growth of knowledge.
Descartes’ method was not experimental but rather an analysis of ideas. He distrusted the senses and held a rationalist view, emphasizing the importance of reason and innate ideas. Inspired by mathematics, his method consisted of four rules:
- Clarity and Distinctness: Accept only clear and distinct thoughts, grasped through intuition, an immediate form of knowledge.
- Analysis: Analyze complex ideas by breaking them down into simpler, clear, and distinct components.
- Synthesis: Reconstruct the analyzed idea to gain a comprehensive understanding.
- Verification: Conduct frequent checks of the analysis and synthesis to ensure completeness and accuracy.
Methodical Doubt
Descartes employed methodical doubt, a temporary and systematic process of questioning all knowledge to uncover undeniable truths. This was not skepticism but a tool to establish a foundation for scientific certainty. During this process, he suspended judgment (Epokhé) until an indubitable truth was found. To guide his actions during this period of doubt, he adopted a provisional morality based on three maxims:
- Sensory Perception: Question the reliability of sensory perceptions, including the existence of the body.
- Deductive Reasoning: Acknowledge the possibility of errors in mathematical and deductive reasoning.
- External World: Question the existence of the external world, considering the possibility of dreams or an evil genius creating illusions.
The Cogito and Substance
In his Meditations on First Philosophy, Descartes’ rigorous questioning led him to the famous “I think, therefore I am” (Cogito ergo sum). He realized that the act of doubting itself implied the existence of a thinking being. This became his first indubitable truth, discovered through the application of his method. He further argued that the mind (thinking substance) was more easily known than the body (extended substance). Through the analysis of a piece of wax, he demonstrated the existence of substance as the underlying reality of changing properties. Substance, a metaphysical concept, could be grasped through reason, not the senses.
God and Epistemology
Descartes presented arguments for the existence of God, including the idea that a perfect being must exist because the concept of perfection cannot arise from an imperfect source. He also argued that innate ideas, such as the ideas of God, the soul, and the physical world, were clear and distinct and therefore reliable. His epistemology emphasized:
- Distrust of the senses
- Underestimation of imagination as a source of knowledge
- Absolute trust in reason
- Intuition as the source of indubitable knowledge
- Deductive method as a tool for extending knowledge
Idealism, Innate Ideas, and Substance (Metaphysics)
Descartes’ idealism influenced philosophers like John Locke. He argued that ideas are the objects of knowledge and the elements of the mind. Only judgments about ideas could be true or false. He distinguished between:
- Adventitious Ideas: Derived from the senses and unreliable.
- Fictitious Ideas: Created by the mind.
- Innate Ideas: Inborn and the foundation of knowledge.
In his metaphysics, Descartes identified three substances: God (infinite), mind (thinking), and matter (extended). God is the cause of the world’s movement and guarantees the existence of finite substances. The mind is characterized by thought and possesses freedom. Matter is characterized by extension and is governed by mechanical laws.
Physics and Linguistics
Descartes’ physics was mechanistic, viewing the world as a machine governed by extension and motion. He believed that animals were part of this mechanical world, their movements externally caused. He rejected the existence of a vacuum and atoms. His laws of nature, derived from God as the first cause, included the principle of inertia, the rectilinear nature of motion, and the conservation of motion.
In his linguistics, Descartes viewed humans as composed of two distinct substances: mind and body. The soul, characterized by thought, is not the source of life but defines the human being. The body is governed by mechanical laws. He acknowledged the interaction between mind and body, with sensations affecting the soul. He attributed error and sin to the misuse of human freedom, specifically the disproportion between the will and understanding.