The Law of Inertia and Its Corollaries

Robert Howard Kroepel
Copyright © 2006
Lakeside Studios
20 South Shore Road
New Durham, New Hampshire USA 03855

The Law of Inertia: An object having an inertial state of being at rest or in uniform motion remains at rest or in uniform motion until acted upon by a force. [1, 2]


1. A force, a form of matter/energy, is a push or a pull which causes accelerations and decelerations.
2. Only a force can cause a change of the inertial state of an object comprised of matter and/or energy.
3. The observation of a change of inertial state implies its cause to be a force of some kind.

The Law of Inertia and its Corollaries are fundamental to physical phenomena at all physical scalar levels, including the scalar level of quantum mechanics, QM.

Causality, objects and events comprised of matter/energy as causes causing as effects (A) changes of the inertial states of pre-existing objects and events or (B) new objects and events, is the basis of determinism.

Although scientists may not yet be able to observe the changes of the inertial states of pre-existing atoms and subatomic particles, they are able to observe the changes of inertial states of percentages of atoms and subatomic particles in known quantities of atoms/subatomic particles, then by Corollary 3 of the Law of Inertia this observation is proof that a force of some kind has caused the observed change of inertial states, and, thus, determinism is occurring at atomic and subatomic scalar levels, including QM scalar levels.

[1] Albert Einstein, in Relativity: The Special and General Theory, Crown Publishers, New York, 1961, translated by Robert Lawson, p. 11:

As is well known, the fundamental law of the mechanics of Galilei-Newton, which is known as the law of inertia, can be stated thus: A body sufficiently far from other bodies continues in a state of rest or of uniform motion in a straight line.

[2] Charles Proteus Steinmetz: The Fundamental Law of Physics

Charles Proteus Steinmetz.
Four Lectures on Relativity and Space.
Dover Publications, Inc., 180 Varick Street, New York, NY 10014 1967
pp. 49–50:

The fundamental law of physics is the law of inertia. "A body keeps the same state as long as there is no cause to change its state." That is, it remains at rest or continues the same kind of motion—that is, motion with the same velocity in the same direction—until some cause changes it, and such cause we call a 'force.' " [Quotes in the original, but not attributed to anyone.]

This is really not merely a law of physics, but it is the fundamental law of logic. It is the law of cause and effect: "Any effect must have a cause, and without cause there can be no effect." This is axiomatic and is the fundamental conception of all knowledge, because all knowledge consists in finding the cause of some effect or the effect of some cause, and therefore must presuppose that every effect has some cause, and inversely. [Quotes in the original but not attributed to anyone.]