Descartes's Philosophy PDF

# Historia de la Filosofía 2º Bachillerato ## Relación entre autores: Descartes y Hume. The discussion about the origin and validity of metaphysical concepts is a crucial point in modern philosophy. The two most important currents of this era are rationalism, of which we take René Descartes as a r...

# Historia de la Filosofía 2º Bachillerato ## Relación entre autores: Descartes y Hume. The discussion about the origin and validity of metaphysical concepts is a crucial point in modern philosophy. The two most important currents of this era are rationalism, of which we take René Descartes as a representative, and empiricism, in which we will select David Hume. They defended opposite positions, although not always totally contrary. Within the rationalist current, we have studied the philosophy of Descartes, in which innate ideas play a fundamental role, that is, concepts that the human being has from the moment of his birth. Examples of them are the concepts of soul, God, substance, world, etc. Innate ideas are fundamental for reasoning and to be able to understand our experiences of other objects. For Descartes, it is clear that these ideas present in the human mind have not been formed as a result of the experiences we have had, given that there is no external experience with which we can relate them. However, Hume carries out a radical critique of the innate ideas of rationalism. Concerned about the meaning and clarity of philosophical language, Hume proposes the principle of copy to know the origin of concepts. This principle says that every idea (weak perception) present in the human mind is a copy of its impression (intense perception) corresponding. In the case where this correspondence does not occur, the idea must be able to be divided into simpler ideas, which must come from an impression. In the case of not being able to carry out this tracking, the idea in question is not legitimate and should not be used in rational reflection. For Hume, innate rationalist ideas are not legitimate, finding their origin in psychological human tendencies. The idea of causality is a principle of association present in the mind; the idea of the self arises by bringing together our perceptions through the principle of similarity and contiguity; the idea of God arises by taking several virtuous characteristics that we experience in things, raising them to their maximum expression and gathering them all into one being. This discussion about innate ideas was later resolved by Immanuel Kant, who proposed in his transcendental idealism that experiences are determined by the subject through the forms a priori of sensibility and understanding. ## Tema de Descartes: El cogito y el criterio de verdad. The rationalism of Descartes is developed motivated by two influential but contrary currents in their theses. The first of these is scholasticism, whose maximum representative is Thomas Aquinas. It is a philosophy that revolves around God, which is dogmatic in what cannot be demonstrated and safe with respect to the conclusions reached through reason. From this doctrine, a strict morality based on religious beliefs is also derived. Descartes, while studying at the Jesuit college of La Flèche, received a scholastic education. The second philosophical current is modern scepticism, which arises in the transition to the Modern Age, motivated by the great advances of the scientific revolution, the religious crisis and the great geographical discoveries. Modern scepticism contrasts with scholasticism, because it focuses on the human condition, adopts an attitude of doubt towards knowledge that can be attained, knowing that human reason has its limitations, and is much more lax and open with regard to morality. Upon reaching adulthood, Descartes abandons scholastic philosophy and decides to immerse himself in the science of his time, given that the physics he knew, that of Aristotle, was already in crisis. At the same time, he believed in the possibility of carrying out a safe science, so he did not accept sceptical theses, which he took as a starting point for building his own doctrine. To do this, he drew inspiration from the method of mathematics, which was yielding such good results. In his Discourse on Method, which was written as a philosophical prologue to three scientific works, Descartes explains what method he has followed to achieve certainty about the truths he presents in those works. The method in question has four parts: evidence, only admitting as true what cannot be doubted; analysis, separating problems into smaller parts for better understanding; synthesis, understanding the relationship between the parts; and enumeration, reviewing to make sure that nothing has been omitted. A fundamental part of this method is doubt, since it is what allows us to achieve certainty about the truths that are at the base of the building of knowledge. Thus, doubt goes through the three famous stages: the doubt of the senses, which we cannot trust because they have deceived us in the past and could do so in the future; the doubt about sleep and wakefulness, according to which we cannot be sure that what we perceive through the senses is real; and the hypothesis of the evil genius, which proposes the existence of a being that makes us believe we are right when we are wrong, so it affects even the truest truths we hold. Unlike the sceptics, Descartes does not use doubt in a destructive way, but to look for a truth that is completely certain. His conclusion is the famous *“I think, therefore I am”* (cogito, ergo sum), which would show that the *“I”* is beyond all possible doubt because to be wrong, or even to be deceived by the evil genius, it is necessary that I exist. In this way, Descartes defends as the first truth the existence of the subject (the I), from which the knowledge of objects external to it will be justified, which will be achieved when the same degree of evidence is obtained as that which is held about oneself. In other words, the criterion of truth is based on the characteristics of clarity and distinction that the cogito presents. However, this approach directly leads to solipsism, the belief that everything that is external to the mind could be pure mental states, with nothing real beyond it. To solve this problem, Descartes resorts to the existence of God. He tries to demonstrate it in two ways. The first of these is based on the metaphysical principle that the superior cannot come from something inferior (which is also used by Thomas Aquinas in the 4th way). Since I can think of God, who is a perfect being, and I am imperfect because I doubt and I am wrong when I think, it is necessary that God be the cause of the idea I have of Him, therefore, God exists. The second way to demonstrate the existence of God is the ontological argument, which Descartes presents as a geometric analogy: God has among his qualities the property of existence in the same way that a triangle has among its qualities that its internal angles add up to 180°. Beyond the validity of these demonstrations, Descartes relies on the goodness of God to ensure that He, as our Creator, would not have endowed us with a reason and senses that would incline us naturally to error, so we can conclude with certainty the existence of our body and the external world.