Action Quote by Isaac Newton
“Thus far I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity. Indeed, this force arises from some cause that penetrates as far as the centers of the sun and planets without any diminution of its power to act, and that acts not in proportion to the quantity of the surfaces of the particles on which it acts (as mechanical causes are wont to do) but in proportion to the quantity of solid matter, and whose action is extended everywhere to immense distances, always decreasing as the squares of the distances.”
About This Quote
Source Letter: “On the Nature of Gravity” (unpublished manuscript), 1687
Newton describes gravity as a universal force acting proportionally to mass, diminishing with distance, yet its ultimate cause remains unknown.
In simple terms: Gravity acts everywhere, linked to mass, but its origin is unknown.
Key Takeaway
Accept mystery while studying observable effects.
Themes
science
gravity
universal law
unknown causes
physics
Mood
inquisitive
analytical
Type
scientific
philosophical
When to use this quote
- astronomy research
- physics education
- theoretical modeling
- philosophical debate
- public outreach
Key Concepts
mechanics
cosmology
philosophy of science
Questions to Reflect On
- What experiments could reveal gravity’s origin?
- How does accepting unknowns shape scientific inquiry?
A Different Perspective
Lack of cause limits full understanding.
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