Descartes, Rationalism, and the Scientific Revolution
Renaissance Influences on Descartes
In the Renaissance, there was a return to the classics alongside a significant influence from Stoicism and Epicureanism. Stoicism, for instance, is evident in Descartes’s very morals. He was also influenced by Skepticism. However, his focus became a question of method for attaining certainty that could not be doubted.
The Rise of New Science and Its Impact
For the development of the new science, Platonism, Pythagoreanism, and the importance of number and geometry were crucial. A decisive factor, however, was the introduction of the mathematical method into experimental research, allowing phenomena to be analyzed with a mathematical mind. Galilean mechanics ultimately led to the scientific revolution with the concept of motion and the principle of inertia.
The consequences of this scientific revolution were significant: a renunciation of the search for root causes or essences in favor of investigating movements; the idea that mathematics represents true and objective reality; the exaltation of human reason as an autonomous source of truth (though reason can be deceived by naive experience if not guided by reasoning about diagrams and mathematics). This mathematization changed the image humans had of the world and themselves, leading to a mechanistic worldview.
Descartes’ Rationalist Philosophy
Descartes held as a basic principle that our true knowledge of reality originates and is based in reason. Rationalists identify rational knowledge with scientific knowledge, particularly mathematics, which they take as a model for knowing. The challenge was applying mathematics to philosophy. Rationalists favored the deductive system, deducing further truths from universal, absolute, and self-evident principles, and sought to identify the origin of these ideas or principles.
The Cartesian Method for Certainty
Descartes attempted to apply the same method to philosophy as was used in science. He saw clarity and evidence in mathematical proofs and sought a method based on the mathematical model that could be applied to all fields, bringing the same clarity and evidence to them. He decided to start from scratch, relying on reason as the sole criterion. For Descartes, the only guarantee of truth is the method, and truth is primarily found in mathematics. Therefore, Descartes’s aim was to find foundational truths that would allow the construction of true knowledge with absolute assurance.
Methodical Doubt
This process is known as methodical doubt, for which there are three main reasons:
- Doubt regarding the reliability of the senses or the material world.
- The dream argument, or the inability to definitively distinguish waking life from sleep.
- The hypothesis of the evil genius, or hyperbolic doubt.
Discourse on Method and Key Concepts
Finally, with his work Discourse on Method, Descartes sought to demonstrate the method for arriving at true knowledge and finding truth. It provides the foundation of the Cartesian method and discusses a new theory of knowledge. His method aims to enhance knowledge, with its basic principle being doubt, as reflected in his famous maxim: “Cogito, ergo sum” (I think, therefore I am). Furthermore, his provisional morality was intended to guide him while restructuring his reason using the discovered method. He also sought to demonstrate the existence of God as a guarantor of all perfect knowledge.