Descartes’ Philosophy: Self, God, and the Mind-Body Dualism
Descartes focused on a unitary conception of reason, aiming for complete knowledge (philosophy) to be used correctly and to achieve true and useful knowledge. Mathematics served as the model for knowledge (objective, necessary, universal, and obvious). He specified two acts of knowing: intuition (where doubt is impossible) and deduction (where reason discovers connections between simple ideas grasped by intuition).
The Cartesian Method
The Cartesian method, based on mathematics, represents the structure of reason, intuition, and deduction. It uses four rules:
- Evidence: Accept only what is accurate as true.
- Analysis: Divide each problem into as many parts as possible, starting with the simplest.
- Synthesis: Sort ideas from simpler to more complex.
- Enumeration: Make complete and comprehensive reviews to verify accuracy.
Descartes believed that applying this method to philosophy would resolve any serious problem.
The Existence of the Self
Descartes considered the existence of the self as the first truism, using “methodical doubt” applied to sensitive knowledge (senses can deceive us, so there is no absolute evidence) and rational knowledge (reason is more reliable than the senses but not infallible). He questioned the ability to differentiate between sleep and wakefulness (we can be deceived by everything around us) and considered the hypothesis of an evil genius (that man would be in absolute error without realizing it, though there is no evidence of this). This radical skepticism led him to doubt everything except the act of doubting itself. The subject can doubt everything except the fact that they are doubting (“I think, therefore I am”).
Misunderstanding and the Nature of Ideas
After establishing the existence of the self, Descartes sought other truths, deductively deriving them from the first truth to escape solipsism. Thinking is embodied in ideas (contents of consciousness, such as love, feeling, desiring, or any psychic experiences). He categorized ideas as:
- Adventitious Ideas: Sensible ideas derived from experience (most numerous).
- Factitious Ideas: Constructed by the understanding from sensitive data.
- Innate Ideas: Existing in thought and belonging to it by nature, or derived from foreign experience and the fruit of imagination; they are obvious and therefore true.
Only innate ideas, evident by their character, can serve to escape solipsism and justify the existence of other substances besides the self.
Metaphysics: The Problem of God
Descartes attempted to explain the existence of God from the idea of God to escape solipsism, using two a priori arguments:
- Analysis of the Idea: The idea of objective reality is more perfect and cannot originate from something less perfect. Its origin cannot be man but God.
- Perfection Argument: If we have not created the idea of God, because it is perfect, then someone (God) must have placed it within us.
Consequences: We know there are two evident substances: God and the self (escaping solipsism). God, being good, eliminates the hypothesis of the evil genius, validating the external world.
Anthropology
Descartes maintained a dualistic vision of man (a radical dualism, a union of two autonomous and independent substances with opposite characteristics):
- Soul: Permanent; its attribute is thought, with two qualities: understanding and will (freedom).
- Body: An extended substance, a machine whose behavior can be explained by the laws of mechanics.
The relationship between body and soul involves the passions (originating physically but influencing the soul). The objective is to control them through reason, avoiding being consumed by them. Will is essential, and freedom is innate.