Redefining Reality - The Intellectual Implications of Modern Science

Kepler’s results were stunning, but no one knew why they would
be true. Aristotle’s circular orbits had a philosophical basis—their
Aristotelianism had a theological foundation. But the reason for
elliptical orbits remained an open problem until Newton.
Isaac Newton developed a simple theory with four basic laws: three
laws of motion and the universal law of gravitation.
applied to it. An object not subject to an external force will
continue its state of motion at a constant speed in a straight line.
The second law of motion describes the behavior of an object
that is subjected to an external force. The acceleration of such
an object depends on two variables: the force acting on the
object and its mass.
The third law applies to the force. For every action, there is an
equal but opposite reaction.
These three simple laws explained a great deal, but they
become incredibly powerful when combined with the law of
universal gravitation. For any objects with mass, there will
be an attraction between them along the line connecting their
centers of mass. This attraction is proportional to the product
of their masses and inversely proportional to the square of the
distance between them.
When these three laws of mechanics and the law of universal
gravitation are used together, they provide an explanation for
Kepler’s elliptical orbits, as well as the tides, the motion of
cannonballs, virtually everything in the world around us.
Not only were Newton’s laws successful in terms of explaining and
predicting, but theoretically, they also undermined the foundation
of Aristotle.
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