Overview
This lecture covers the early Greek philosopher Thales, his significant shift from mythological to rational explanations of nature, and his theory that water is the fundamental substance of the universe.
Thales and Pre-Socratic Philosophy
- Thales lived in the 6th and 5th centuries BC in modern-day Turkey.
- He is considered the first pre-Socratic philosopher, setting the stage for later Western philosophy.
- Unlike other Greeks, Thales rejected the unpredictable Greek gods as explanations for natural phenomena.
- He sought predictable laws in nature and believed the world could be understood through reason and inquiry.
Thales' Theory of the 'Arche'
- Thales proposed that everything is fundamentally made of water.
- The 'arche' (unifying principle) is the underlying substance connecting the diversity found in nature.
- Thales' arche was not supernatural but a material substance observable in the world.
- Water was chosen as the arche because it explained motion, life, and transformation in nature.
Reasons for Water as the Arche
- Water appears to move on its own (rivers, tides) and seemed alive to those without knowledge of gravity.
- All living things require water, emphasizing its importance for life.
- Thales observed islands forming and believed the earth originated from water, thinking the earth floated on water.
- He noted substances change forms (solid, liquid, gas) and thought water could explain this transformation.
Thales as a Scientist
- Thales is credited with predicting the solar eclipse of May 28th, 585 BC.
- His predictive ability gave him credibility in the ancient world.
Key Terms & Definitions
- Pre-Socratic philosopher — a thinker who lived before Socrates and sought rational explanations for natural phenomena.
- Arche — the principal substance or fundamental element underlying all things.
Action Items / Next Steps
- Review the main concepts of the pre-Socratic philosophers.
- Prepare to explore other pre-Socratic thinkers and their contributions in upcoming lessons.