Week 6 — Newton II and Newtonian Anomalies¶
Newton's Achievement¶
Newton unified terrestrial and celestial physics.
The same laws explain:
- falling apples
- planetary orbits
Laws of Motion¶
- Inertia
- Force equals mass times acceleration
- Action and reaction
Universal Gravitation¶
Every object attracts every other object with a force proportional to:
- their masses
- inverse square of their distance
Philosophical Significance¶
Newton demonstrated that a small set of universal laws could explain a vast range of phenomena.
This created a powerful vision of the universe as a mathematical system governed by universal laws.
Newton's theory also raised philosophical questions.
Gravity appeared to act at a distance, with no visible mechanism.
Critics argued this resembled mystical or occult forces.
Newton's response was methodological.
Science should describe how nature behaves, even if the underlying mechanism remains unknown.
This marks an important methodological stance:
Predictive power can justify scientific theories even when deeper explanations are incomplete.
Newtonian Anomalies¶
Even Newton's framework encountered difficulties.
Examples include:
- irregularities in planetary motion
- unexplained perturbations
Philosophical Significance¶
No scientific theory perfectly explains everything.
Even highly successful theories contain anomalies.
This reinforces Kuhn's insight:
Scientific paradigms remain stable despite anomalies until a better alternative emerges.