Plato and Descartes: Philosophies of Ideas, Knowledge, and Existence
Plato’s Socratic Dialogues (399-389)
After Socrates’ death, some followers sought refuge in Megara; Plato may have stayed there a few years. He traveled to Cyrene and then Athens. Around this time, he wrote his first dialogues, showing fidelity to Socrates and referencing the theory of ideas in Euthyphro.
Dialogues of Youth:
- Apology of Socrates: Defense of Socrates
- Crito: The Death of Socrates
- Laches: Value
- Charmides: Temperance
- Lysis: Friendship
- Euthyphro: Piety
- Ion: Poetry
- Protagoras: The Arete
Transitional Dialogues (388-385): Plato traveled to Italy, contacting Pythagoreans and gaining insights on the immortality and transmigration of the soul, cosmology, and mathematics. He visited Sicily, ruled by Dionysius I, befriending Dion (Dionysius I’s brother) and living at court until the tyrant sold him into slavery. Back in Athens, he founded the Academy, inspired by Pythagoreans and Socrates, and began developing his doctrines.
- Gorgias: Rhetoric and justice
- Meno: Immortality and reminiscence
- Cratylus: Language, theory of ideas
- Hippias Major: Beauty
- Hippias Minor: Lying and truth
- Euthydemus: Sophistic eristic
- Menexenus: Parody of funeral orations
Dialogues of Maturity (385-370): Plato directed the Academy in Athens, delving deeper into his most important theories.
- Banquet: Theory of ideas of love
- Phaedo: Preparing for death and immortality of the soul
- Republic: Justice
- Phaedrus: Love, beauty, and soul
Dialogues of Old Age (369-347): Plato revisited Dionysius II in Syracuse, but his teachings led to imprisonment. Returning to Athens, he questioned his theories, becoming increasingly pessimistic, resulting in critical dialogues.
- Parmenides: Self-criticism of the theory of ideas
- Theaetetus: Search for knowledge
- Sophist and Politico: Method definition (diairesis)
- Philebus: Search for pleasure and the good
- Timaeus: Cosmology
- Critias: Primitive Athens
- Laws: Ideal city
Theory of Ideas
Characteristics in the dialogues of maturity:
- Ideas are essences of things (what makes a thing what it is).
- Ideas exist apart from particular things, as real and independent entities.
- Duplication of the world: the sensible world of particular things and the intelligible world of ideas (myth of the cave, or line).
- Every idea is unique, eternal, and immutable (Parmenides’ characteristics).
- The relationship between ideas and things is a partnership; ideas are the cause of things.
- The soul and mathematical things act as intermediaries between both worlds.
In old age, Plato rethinks the theory of ideas due to criticism and self-doubt:
- What kinds of ideas exist? Moral, aesthetic, mathematical, relationships, but not contemptible things…
- Relationship between ideas and things? Third Man Argument (Parmenides). Still, he supports the theory, or thought has no direction.
- Relationship of ideas? Hierarchy in the intelligible world: Idea of the Good, ethical/aesthetic ideas, then mathematical.
- Relationship between ideas and numbers? Three types: Ideals, mathematical, sensitive. Ideas are numbers, each associated.
Cosmology
Plato’s late-life cosmology in Timaeus explains the world using Pythagorean elements. The Demiurge, an active, intelligent cause (inspired by Anaxagoras’ Nous), orders chaotic matter in space according to an eternal model (World of Ideas). Features include:
- Teleological conception of the Cosmos (Demiurge’s optimism)
- Mathematization of everything (mathematical structure in bodies, geometry)
- Deification of the Cosmos (stars as gods)
The Soul
Plato posits a tripartite soul:
- Rational Soul: Intelligible knowledge, wisdom, located in the brain
- Irascible Soul: Courage, will, strength, located in the chest
- Appetitive Soul: Control of passions, temperance, located in the womb
He affirms the soul’s immortality and divine character, associating it with the intelligible world. Phaedo focuses on the soul’s immortality. The body is a prison, hindering contemplation of ideas. The philosopher seeks death to free the soul, which then travels the world of Ideas. Philosophy prepares for death, following the Pythagorean doctrine of reincarnation.
Knowledge and Love
How is it possible to know whether the ideas belong to another world? 1-The Reminiscence -> To know is to remember, our soul has previously referred to the ideas and has the total knowledge, once we die the soul travels to the intelligible world which includes all the ideas to achieve wisdom. After this, the soul returns to the sensible world to reincarnate in another body which will begin with a knowledge from scratch. You will have to go gradually learning to reach enlightenment, knowledge and remember everything. 2-The Dialectic -> Plato proposes as the dialectic method to reach the world of ideas. This is an activity knowable based on the exercise of reason, in order to know the world is intelligible ideas. Its ultimate goal is to get to know the idea of the Good, the dialectic is not based on any collection, nor accept any image hypothesis. (Ascension to be) 3 “Love -> ascent from the case until the supreme idea. Things serve as steps up to the idea, participate as degrees of the idea. Platonic love is an ascent to beauty then. Virtue and the state to reach the ideas is necessary not only love and dialectic, but it also virtue, towards the Good and Justice. Virtue and the state allows access to ideas. The virtue or arete indicates overall excellence, has an innate nature and can not be taught or learned.The Sophists make it into the art of life and mastery of it, so it is teachable and learnable. Virtue can have three concepts: “Virtue and wisdom -> Knowledge is the higher order, the conocimeinto of Ideas of the Good, Justice, Valor … Plato attempts to unify all the virtues in the Idea of Good. “Virtue and purification -> The virtuous man is he who purifies his soul from the passions and the body follows in order to make access to ideas (Pythagorean). Plato accepts life where there is mixed pleasure with moderation. “Virtue and Harmony -> The justice is considered as fundamental under the agreement consisting of three parts of the soul. This means that the rational part must dominate the irascible and appetitive these two to get it and who will be harmonious and fair. The state that Plato dreams of building is one where the death of Socrates is impossible, where there is no corruption or degradation of the government, so the only solution to this is that governing is someone truly wise and not corrupt and this has to be the philosopher. This state is also composed of three social classes that correspond to parts of soul: Sound – Governantes or philosophers – Prudence Irascible – Guardians – Fortaleza appetite – Artisans and farmers – Temperance Harmony – Harmony – Justice degradation status: Aristocracy -> timocracy – > Oligarchy -> Democracy -> Tyranny. Theological conception of the cosmos: it is a conception teolologica the first onthe history of filosofia.Platón considers that the end is the main cause to be used to explain everything, however the pre-Socratics had used as an explanation of the matter only COSOMA (alementos material) and a principle of the movimiento.
Rationalism Rationalism data on the seventeenth century where Descartes begins this philosophical thought which no other source of knowledge that was not the reason for rejecting the faith and revelation. We can highlight the following features: · full confidence in human reason: This is the only one who can lead men to knowledge as opposed to faith, revelation, the senses or the imagination that we are only deceiving. For some reason draw the first and fundamental truths (innate ideas) from which we can deduce all the others and build the system in the world. · Search a new method: then we must seek an appropriate method of reasoning, a method of discovering and this is the mathematician, as the philosophical system requires the same evidence that a mathematical system. For this the perfect model will be the principles of Euclidean geometry. That is, to establish definitions and axioms from which it may derive, after deducting all with evidence and need a closed and complete philosophical system. · Subjectivity and Reality: It is mechanistic, the world is a machine whose explanation is not precise or substantial forms, neither the management nor the hidden qualities of the Aristotelians finalistic. With the subjectivism man is a being back on itself knows nothing but his own thoughts, the reality of the world because it is not clear, must be deducted. Here is the fundamental problem of modern philosophy, the problem of knowledge. And then build a metaphysics that is based on the concept of substance, which is the innate idea which derived all.Life Descartes was born in La Haye (France) in 1596, studied at the College of the Flèche run by the Jesuits there, he graduated in law at Poitiers, but is dissatisfied with the teaching received, all he has learned and it was almost is involved in growing doubts increasingly recognizing their own ignorance. Excelled in philosophy and mathematics, there began to think that such a shaky foundation that has the philosophy at that time, should be based and evidence as surely as math, strangers who have not done so already. Start to travel and see the world in order to learn more and more, until in 1618 he discovers his own method with the idea to rebuild and unify all the sciences. This time it focuses entirely on how to perfect his method and getting rid of errors goes to the Netherlands, where tolerance reigns and take refuge philosophers, begins to slowly spread his thought in Europe but the condemnation of Galileo it slows the limiting their feet and avoiding plans to publish his works that could have high impact. Is cautious to avoid any type of conviction, finally dies misunderstanding tired to give your new philosophy at Stockholm, 1650. Evolution is not considered much change but the great effort in developing your idea and finish the job. The philosophy that until then had no solid foundation needed to rebuild from scratch and work here Descartes, making no specific interest, and if they served the other, the better. For this, the Descartes project based on the unification of all sciences into one shown in the following locations: • All science is human wisdom, all belong to the same matter how different the objectives of each. · Poses a unique and universal method for all sciences, thus opposed to the Aristotelian philosophy. Adopt as a mathematical method contrary to the attitude of Aristotle. • All science because, however different they may be, will form an organic unity. · This project will then: a) formulation of a method b) formulation of a provisional moral standards c) development of all beginning with the metaphysical sciences, along with physics and concluding with all others. The method The method of Descartes therefore provides certain rules and easy, from which we can achieve true knowledge of everything that we can. Thus, the method avoids the error, and contrary to Aristotle, is not a simple method of exposure (ars exponiendi) but can increase knowledge, discover new truths (ars inveniendi), the rules of the method are summarized in 4 – Evidence : Do not conceive of something as true that not so clear and distinct that there is no way to dispute it. – Analysis: Divide the problem into as many parts as possible in order to examine it carefully and not get any errors make sure everything is true. – Summary: Return to compose starting with the simplest and easiest to know even the most complex. – Verification: Return to review and order as complete as possible to ensure that we will not make any mistakes. The methodology of Descartes gives preference to conceptual analysis, the Cartesian method is directly related to the deductive methodEuclid thus producing a long chain of inferences from the simple and obvious principles. Descartes believes that there are two simple natures, extension and thought as well as all the principles from which you can legitimately deduct some are innate ideas. But they are not the same as the Platonic reminiscence, these ideas are potentially arise in our minds and in certain experiences. -> Is inspired by St. Augustine. Cogito ergo sum Metaphysics methodical doubt. So, first of all need a first truth absolutely clear that serve as a starting point to begin to figure out everything, building a deductive system, based on the idea of substance. Since founding the philosophy, this should be followed by absolute evidence, Descartes decides doubt above all to find something that is certain and true, as this will serve as the first principle of philosophy quite evident and starting point. Finally just concluded that the only thing that can not doubt is that doubt, and therefore thinks that exist at the time, this is systematic doubt that helps you find your pulse. Doubting of the senses, our reasoning, and even the reality of the world but repeating it again, what resists doubt is that he is hesitating. Note that this will not be a deduction if not intuition, immediately evident, clear and distinct idea. And hence the concept substance extracted will be fundamental. The substance will then be the existing concrete, which needs nothing but itself to exist. But he also discovers that there must be two substances, as if only God is substance, as the creatures need to exist it must have two types of substances then: · Substance Infinite (God) does not need absolutely no one but her to be. Discover the soul then there is a unique idea, the idea of perfection and it can not have been built for yourself or come from outside, because neither self nor other things are perfect, it must be an innate idea of someone actually making perfect God. Ontological Argument-> Anselm of Canterbury-> Proslogion All Cartesian system rests therefore on the existence of an infinite substance. Empelea Descartes methodical doubt to reach their goal, can be seen clearly through the arugmento recuerso malignant tevñes which just concluded truth that the only thing that we can be eSecurity exitencia is our own. · Substance Finite: The soul as being finite does not need any other finite substance to exist so the body does not need to exist. The soul is a finite substance whose only attribute is the thought. Descartes Res Cogitans call the soul, its essence is to think he can not pretend not to think (as a demonstration of Galileo). The body then is not whether that extent and no substance (res extensa). And has two modes which are contained and motion, Descartes geometrizes the corporeal world and limited to pure extension. Physics Scientific method is therefore a deductive method from the idea of God as creator and preserver of the world and certain innate ideas in the human mind. In his method of analysis is synthesis, ie a deduction, until then the procedure does not require experience, is also based on cause and effect. But there comes a point where the causes are limited and can not deduct more from their causes, and here is where the expertise to determine which of these effects are being performed. So the experience will be worth to check the assumptions deductive but only from a certain level of deductive process.The mechanistic world is conceived as a machine, it comes down to matter and motion, but only matter is extension and therefore we concluded that: “There are no recent indivisible particles, it is inconceivable that the extension can not be divisible indefinitely “There is no vacuum, everything is full of stuff. He denies the objectivity of secondary qualities and the existence of any intrinsic active things. Descartes eliminates the hidden qualities (act and potency) of the Aristotelians and thus eliminates all forces. There will be no force of gravity as it is not possible to form clear and distinct idea of it and everything will be explained by contact movement within a space filled, where the origins of the movement God will use Descartes. Laws of God is the nature · first cause of motion and preserves the same amount of movement in the world. · Thus derived the three laws of nature, the second causes of all movements: “First law of nature: everything remains in the state in which it is if nothing changes. “Second law of nature: A moving body tends to continue its motion in a straight line. “Third law of nature: At no time is lost part of the energy in the movement, transmitting only. Conservation movement. The Universe The universe is composed of a set of vortices of matter that is touched each other and are of different sizes, plus there are three kinds of stuff: light (sun and stars), transparency (ether), opacity ( Earth). Physiology Descartes gives a mechanistic explanation to the agencies, which seen as very complex machines. Descartes rejected the existence of a vegetative or sensitive soul to explain life, the animals are machines. Unexplained is the relationship of human soul with the body itself, which assumes that this process is done through the pineal gland, this will be the turning point of Descartes and where Hoops launch a devastating criticism of his philosophy. Demonstration existence of God: This is a reduced version of Anselm’s argument. In fact, the line of reasoning followed by San Anselmo would be a reductio ad absurdum as follows: 1.di is an entity such that nothing greater can be. 2.The concept of God exists in human understanding. 3.Dios exists in the mind of oneself but not in reality. 4.Si God existed in reality, it would be something much grander than the existence of God in one’s mind. 5.Using based on [1], it follows [4] that God really must exist. Speaking of greatness, the semantic argument loses force, however recover if it follows the line of reasoning of Descartes, which aims to God as the most perfect being that can exist (one that lacks imperfection).