Descartes and the Cartesian Method: Achieving Certainty

The Cogito and the Criterion of Truth

In reaction to the anarchy of the late 16th century, a need arose for a rigorous method of analysis and study. René Descartes discovered his method by considering mathematical procedures. The Cartesian method was intended to have universal value, proposing three primary goals:

• Formulate clear rules.
• Establish universal metaphysical foundations.
• Demonstrate the method's fertility across all branches of knowledge.

Descartes' anti-skeptical position and his interest in science impelled him to reject error, investigate with certainty, and pursue the truth.

Defining the Cartesian Method

Descartes defined his method through specific objectives:

• Establish rules that are certain and easy to follow.
• Avoid mistaking the false for the true and vice versa.
• Prevent wasted intellectual effort.
• Gradually increase knowledge to the limits of reason.

The Four Rules of Reasoning

Descartes proposed four rules to seek the truth. The first two constitute the analytical method, while the last two constitute the synthetic method:

1. Evidence

Accept as true only what is clear and distinct. An idea is clear if it is manifest to the intelligence; it is distinct when separated from other ideas. Through intuition—the concept of a pure and attentive mind arising from the light of reason—we arrive at evidence.

2. Analysis

Divide each difficulty into as many parts as possible to examine them more effectively.

3. Synthesis (Summary)

Direct thoughts from the simple and easy to the complex. This is the orderly process of geometry. For Descartes, deduction involves the subsequent intuition of simple natures and the connections between them, breaking objects into simple elements (analysis) and rebuilding the complex deductively (synthesis).

4. Enumeration

Conduct comprehensive and general revisions to ensure nothing is omitted.

Methodological Foundations

These four rules form the constructive, positive Cartesian method, synthesizing logic, geometrical analysis, and algebra. Three concepts underpin these rules and justify the claim of certainty:

• Intuition: The knowledge base that separates truth from falsehood; a natural light or instinct of the pure mind.
• Deduction: The inference used to derive new ideas from those already known.
• Order: The creation of a logical layout to replace the apparent chaos of sensory experience, which is the ultimate goal of science.