Descartes' Four Rules of Method: Foundation of Rational Knowledge
Descartes' Critique of Scholasticism and Experience
Descartes, formed in scholastic philosophy, warned that this philosophy did not respond to the issues and concerns of its time. Instead, he found in mathematics a secure and rigorous science used to develop his method. In empirical experience, the subject is passive, and the knowledge that experience provides is doubtful. In contrast, in mathematics, the subject is active, leading to clear and certain knowledge. This certainty stems from the knowledge itself, without recourse to experience.
Therefore, Descartes departs from experience and seeks reason as the foundation of his method and the justification of all knowledge.
Defining the Cartesian Method
Descartes defined his method as: “a certain set of rules, easy to observe, making it impossible for anyone who observes them carefully to take the false for true, and which gradually lead to the knowledge of everything that is capable of knowing.”
Descartes formulated four rules or steps that comprise the method:
The Rule of Evidence (Regla de la Evidencia)
This is the first and most important rule: to accept as true only that which presents itself with the characteristics of clarity and distinction. This means accepting only what satisfies the conditions of intellectual evidence. It is the result of intuition, which is the manifestation of knowledge in the mind.
- Clarity: The manifestation of knowledge in the mind.
- Distinction: The separation of such knowledge from all others (Descartes calls these clear and distinct ideas Simple Natures).
The mind reaches these evident principles through intuition, which is the first operation of the spirit.
The Rule of Analysis (Regla del Análisis)
This is the procedure of research consisting in dividing each of the difficulties we encounter into as many parts as possible to get to the simplest elements. The truth of these simplest elements can be established by an act of intuition. This is the process the mind must follow to reach the Simple Natures.
The Rule of Synthesis (Regla de la Síntesis)
This consists in proceeding with our thoughts in order, passing from the most simple and easy to learn to the knowledge of the most complex and obscure. Once we have the self-evident truth of certain statements, we deduce more complex statements from the preceding ones. This process corresponds to the second fundamental operation of the spirit, which is deduction.
The Rule of Enumeration (Regla de la Enumeración)
This consists of reviewing carefully each of the steps taken in the operations until we are sure not to miss anything and have not committed any mistake in the deduction.