A Posteriori Knowledge and Philosophical Concepts

A Posteriori Knowledge

• Defined as knowledge gained after experience.
• Contrasted with a priori knowledge, which is based on pure thought.
• Example: Learning from an experience or instinct.

Metaphysics, Ontology, and Logic

• Metaphysics: Refers to the world of forms (Plato).
• Ontology: The study of the existence of different things.
  • Analyzes and categorizes the reality of different entities.
  • Example: Distinguishing between the plane of existence of humans versus gods.
• Logic: A system of rules for deriving true inferences from premises and conclusions.
  • Premise: A statement.
  • Conclusion: What follows from the premise.

Epistemology and Aesthetics

• Epistemology: The study of where we get our knowledge.
  • Different forms of knowledge are gained from math, art, and literature.
• Aesthetics: Concerns beauty and theories about beauty in society.
  • Explores whether beauty is objective or subjective.

Ethics and Politics

• Ethics: Morality; individual opinions on what is right and wrong.
• Politics: Ethics applied at a societal level.

Trolley Problem

• A famous ethical thought experiment.
• Scenario: Choosing between sacrificing one person you know to save multiple strangers or vice versa.
• Utilitarian viewpoint: Sacrifice one to save more people, securing happiness for the greatest number.

Mythos and Logos

• Mythos: Explanations based on myths and appeals to gods.
  • Example: An event happening because “Zeus banged one chick one time.”
• Logos: Rational explanations based on reason and science.
  • Example: An event happening because of a preceding natural cause. Like science
• Both mythos and logos have contributed to our present understanding.

Athens and Jerusalem

• Athens: Gave us liberated rationality, marking the beginning of rational and scientific thought in human history.
• Jerusalem: (Not detailed in the transcript but implied to represent a contrasting philosophical and religious tradition).

Thales of Miletus

• Considered the first philosopher and scientist.
• Lived in Miletus (Ionia, Greece, modern-day Turkey) around 500 BC.
• Studied natural philosophy (science, biology, physics).
• Theory of Water: Believed water was the primary element and the base of everything.
  • Earthquakes were thought to be caused by the Earth floating on water.
• Significance: Attempted to explain the world through rational inquiry rather than attributing events to gods.

Anaximander

• Student of Thales.
• Rejected water as the primary element.
• Proposed an indescribable element similar to ether or aerosol as the base of everything.
• Concept of Binary Opposites: Believed the universe is composed of binary elements like hot and cold, but no single element dominates due to a sense of justice.

Anaximenes

• Student of Anaximander.
• Proposed air as the primary element (reminiscent of the Avatar concept).

Milesian/Ionian School

• Thales, Anaximander, and Anaximenes.
• Sought to understand the fundamental components of matter.

Pre-Socratics

Empedocles

• Believed he was a god and should be worshipped.

Atomists: Leucippus and Democritus

• Believed that stuff is made of atoms.
• Democritus: Historical records confirm his existence; he lived in Athens and met Socrates.
• Concept: Seemingly we never touch, referring to the atomic level.

Heraclitus

• Believed the universe is in a constant state of flux.
• “You cannot step in the same river twice” because the water and the person have changed.

Concept of Void

• Exploration of whether the void (absence of something) exists.
• Argument: If the void is something, it is not void.
• Experiment: Using a vase to demonstrate that the space inside contains air, not nothing.

Atomists and the Void

• Debate: If the world is made of atoms, what is between them?
• Answer: The void.
• Counter-argument: If the void exists, it is something, leading to infinite regress.

Pythagoras

• Vegetarian who abstained from beans, claiming they smelled like semen.
• Formalized and proved the Pythagorean theorem: $a^2 + b^2 = c^2$

Orphic and Bacchic Cults

• Pre-date Athens’ golden age.

Orphic Cult

• Associated with Orpheus, often depicted as a physician.
• Killed by maidens (worshippers of Bacchus).

Bacchic Cult (Dionysiac)

• Associated with Bacchus (Roman) / Dionysus (Greek).
• Dionysus was born twice: first naturally, then from Zeus’s leg after Zeus saved the fetus and sewed it on his leg.
• Worshippers engaged in ecstatic rituals, including tearing animals apart.
• Empedocles was likely a Bacchic follower.

Pythagorean Beliefs

• Believed in reincarnation of the soul.
• Story: Pythagoras stopped someone from beating a dog because he believed it could be the soul of a friend.
• Reasons for bean abstinence:
  • Beans looked like human fetuses.
  • Contained human souls.
  • Resembled genitalia.
  • Smelled like semen.

Pythagorean theorem proof

• If two legs of a right triangle are 1, then the hypotenuse is $\sqrt{2}$.
• Pythagoras was persecuted and eventually killed for his beliefs.

Anaxagoras

• Hired by Pericles.
• Idea of Physics: Everything contains all elements, but in varying concentrations.
  • Example: A loaf of bread contains fire, earth, wind, and water, but more earth than fire.
  • Even snow contains black matter.
• Analogy: Like RGB color selectors red, green, blue, every color is derived from RGB.