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.