Journey Through Philosophical Thought
Ancient Philosophy: Exploring the Cosmos and Human Existence
Thales
Water as the origin of all things. The first scientist to move beyond a god-centric worldview. Introduced two key postulates of science: the universe is governed by laws, and humans can understand these laws. Famous for predicting a solar eclipse.
Pythagoras
Number as the foundation of reality. Believed everything could be expressed numerically. The discovery of the irrationality of the square root of two challenged his worldview.
Heraclitus
Everything flows, everything changes constantly. Our actions must adapt to this continuous change.
Parmenides
What is, is. What is not, is not. Change is an illusion, as it implies something coming from nothing.
Empedocles
Multiple origins of existence. Proposed fire, earth, air, and water as the unchanging fundamental elements.
Protagoras
Man is the measure of all things. Truth is subjective and individual, changing throughout life.
Gorgias
Skeptical of true knowledge. Questioned the possibility of knowing and expressing reality.
Socrates
“I only know that I know nothing.” Focused on self-knowledge and educating others. Accepted his death sentence in obedience to the law.
Plato
Knowledge as recollection. Proposed two worlds: the world of unchanging ideas and the world of sensory experience. The soul belongs to the world of ideas.
Aristotle
Innate human desire for knowledge. All knowledge begins with experience.
Epicurus
Pleasure as the foundation of a happy life. Epicureanism emphasizes intellectual and physical pleasure, but not hedonistic excess.
Seneca
Stoic philosophy. Everything happens for a reason. Death is freedom.
Medieval Philosophy: God and the Supernatural
Augustine of Hippo
Believe to understand. Faith precedes understanding of God.
Anselm of Canterbury
Attempted to prove God’s existence. “The fool says in his heart, there is no God.”
Thomas Aquinas
Faith and reason as equal paths to God.
William of Ockham
Faith for the supernatural, reason for the natural. Good is good because God wills it.
Modern Philosophy: Human Knowledge
Renaissance
Niccolò Machiavelli
The end justifies the means (in politics).
Galileo Galilei
Promoted the scientific revolution. The universe is written in the language of mathematics.
Thomas Hobbes
Man is a wolf to man. Freedom leads to chaos.
Modern Era
René Descartes
“I think, therefore I am.” Initiated rationalism.
David Hume
Empiricism: all knowledge comes from experience.
Immanuel Kant
“Dare to know.” Encouraged critical thinking and independent thought.
Georg Wilhelm Friedrich Hegel
German idealism. The real is rational, and the rational is real.
Contemporary Philosophy: Critique and Revision
Karl Marx
Marxism. “Religion is the opium of the people.”
Friedrich Nietzsche
God is dead. Emphasis on the will to power.
Sigmund Freud
The unconscious mind. Guilt as a major obstacle to cultural evolution.
Branches of Philosophy
- Metaphysics: Study of being.
- Logic: Study of valid arguments.
- Epistemology: Study of knowledge.
- Ethics: Study of morality.
- Aesthetics: Study of art and beauty.
Women in Philosophy
- Ancient: Hypatia of Alexandria.
- Medieval: Hildegard of Bingen.
- Modern: Ada Lovelace.
- 20th & 21st Century: Hannah Arendt, Simone de Beauvoir.
Limits of Knowledge
- Dogmatism: Certainty of knowledge (Descartes).
- Skepticism: Doubt about knowledge (Pyrrho).
- Criticism: Knowledge is revisable (Kant).
- Relativism: Truth is context-dependent.
- Perspectivism: Individual truths (Ortega y Gasset).
Epistemology
The branch of philosophy that analyzes knowledge. Foundation for other sciences.
Concepts of Knowledge
- Opinion: Subjective and uncertain.
- Belief: With or without certainty.
- Knowledge: Certain belief, but not always provable.
Types of Knowledge
- Theoretical: Explaining the natural world.
- Practical: Knowing how to act.
Truth of Facts vs. Propositions
Truth of facts: True reality vs. apparent reality.
Truth of propositions: Truth as correspondence (Aristotle), coherence (Hegel), or success.
Formal truth: Coherence within a system.