Plato and Kant: Philosophical Foundations
Plato’s Philosophy
Theory of Ideas
Background: Knowledge requires stability and permanence of its object. There can be no science of the sensible world. This creates a dualism: the world of sense and the intelligible world.
Existence of ideas: The being of things, essences. They are the causes and purposes of sensible things. They exist separately. They are human concepts. The idea of property is responsive suprema. The sensible world is a copy and imitation of the world of ideas. The sensible “is” part of the world because it is eidetic.
Cosmology
Treats the source of the sensible world. Elements training prior to the cosmos: matter, ideas, and a Demiurge. The demiurge ordered the matter, bearing in sight the eidetic world. He creates the universe by imitating the world of ideas. The cosmos is like a living being with a soul of its own: the soul of the world. Teleologism: The aims are explanatory causes.
Platonic universe: finite, closed, spherical.
Anthropology
Man is composed of a soul-body dual. Accidental union of these two substances. Soul: the immortal part of humans (identified with rationality), a substance distinct from the body. Intermediate reality that connects the two worlds. Tripartite division of the soul: rational (caution), irascible (value), concupiscence or appetitive (temperance). Only the rational is immortal.
The body belongs to the sensible world and is the prison of the soul.
Theory of Knowledge
Reminiscence: Following the immortality of the soul, knowing is remembering. Dialectic: degrees of knowledge (doxa and episteme) which correspond to degrees of being (the world of sense and the intelligible world). The dialectic is pure intuition of the idea, a method of knowledge and true knowledge.
Eros: through access to the world of eidetic things.
Ethics
- Shakes sofista.
- Virtue relativism as purification.
- Intellectual moralism.
- Harmony between the three parts of the soul leads to justice.
Politics
- Trying to create an ideal state (Republic).
- Each class applies to what belongs to nature as part of the soul to prevail: rational (ruler), irascible (guardians), appetitive (producers).
- Banana-communism of property, women, and children.
Influences and Repercussions: Plato’s work revisits issues covered by pre-Socratics: the fact that the world is conceived as Heraclitus, subject to permanent change, is a history of the sensible world. By contrast, immutability, perfection, and eternity coincide with Parmenides’ ideas. The Pythagoreans influenced the dualism of body/soul, immortality of the soul, and reincarnation. Mathematics is evident in the ordering of Anaxagoras. Intelligence (nous) is a precursor to the Demiurge. Plato’s drive for change is partly due to the Sophists and Socrates, replacing the study of cosmology with the study of man. Following Socrates, he confronts the Sophists. Dialogue is a Socratic inheritance. Plato’s Academy became the most important center of studies in antiquity. Aristotle critically formed his theory of ideas as transcendent realities independent of the physical world. Neoplatonism inherits the mystical aspect of Platonic doctrine, influencing Saint Augustine and Thomas More’s Utopias. The Republic is Plato’s model, though criticisms range from realism to lack of totalitarianism. Kantian noumena are inaccessible, and ideas are only accessible by reason, not sensitivity. In ethics, Plato gives predominance to reason over inclinations. Currently, the Platonic conception is based on the search for universal values.
Kant’s Philosophy
Uses of Reason
- Theoretical use: What can we know?
- Practical use: What should we do?
Theoretical Use of Reason
Transcendental Idealism: The validity of the judgments of science depends on two factors: 1. Empirical data (contingent and probable) 2. Categorical terms a priori and the transcendental subject (universal and necessary). The question is: What are the conditions for the possibility of scientific knowledge (universal, necessary, and extensive)?
Types of cases:
- Transcripts: a priori explanatory.
- Synthetic universal and necessary a posteriori: extensive, probable, and contingent.
- Synthetic a priori: extensive but universal and necessary (a priori) are the judgments of science.
Critique of Pure Reason:
Transcendental Aesthetic: Mathematics as a science is possible due to pure a priori forms of sensibility: Space and Time.
Analytic and crucially, physical science is possible as pure a priori forms of understanding: the categories.
Transcendental dialectic metaphysics is possible as a science.
Practical Use of Reason
Starting point: verification of the existence of moral conscience. There is a sense of universal duty, a moral law. The moral law must be an objective, a priori, universal, formal, and autonomous moral principle.
Imperatives: Hypothetical: subordinate to a condition. Categorical: do not impose any content to the action, only a way. Moral action is governed by the categorical imperative.
Formulation of the categorical imperative: Act so that the maxim of your will can always be worthwhile as a principle of universal law.
The postulates of practical reason: freedom, the existence of God, the immortality of the soul.
Influences and Implications: From Rationalism, Kant took the idea that scientific knowledge is universal and necessarily true, so there is some factor in the a priori reason from the influence of the subject. Hume made him aware of the importance of experience and limits the use of reason. He rejects the possibility of metaphysics as a science: God, the soul, and the world can be thought of but never known. From Rousseau, Kant understands the finitude of human happiness and therefore complements it ethically. From Pietism in his youth, he took the ancient Stoics’ ethics of virtue. Kant reformulated Plato’s ideas by placing them in the reason of the subject and his intellectualist ethics. The repercussions resulted in the first end of the nineteenth-century German idealism, whose principal representatives built great philosophical systems to explain all reality, above the line proposed by Kant. This criticism culminated in Marx and Schopenhauer’s dialectical conception of history. Schopenhauer collected the Kantian concept of the thing-in-itself, identifying it with the will as an irrational principle of reality. Nietzsche criticized Kantian formal ethics of duty as oppressive to life. Kant’s influence is detected in neo-Kantianism, which tried to synthesize Kant’s thought, the ratio-vitalism of Ortega y Gasset, who criticized Kant’s pure reason for its abstraction, trying to link it to life, and the critical realism of writers like Hartmann. Others like Scheler criticized Kantian formal ethics, putting up the material of values. Heidegger and Sartre proposed a formal ethics of freedom, inspired by Kant but atheistic. Wittgenstein swapped the limits of reason for an analysis of the limits of language through which to express our knowledge.