Simple Book Review: Isaac Newton (Laws of Motion)

Isaac Newton: Laws of Motion (1998) by Michael White

[For the person of Isaac Newton I would like you to refer to my summary on Giants of Science: Isaac Newton (2006) by Kathleen Krull. But here I would like to simply explain and focus on the first Newton’s law of motion]

There are three laws of motion stated in Newton’s most famous book Philosophiae Naturalis Principia Mathematica (usually referred to as the Principia). But the first law, which deals with the concept of inertia, has the widest applications today. Inertia is the term given to the tendency for all objects to resist change or movement. In order to move an object, a force has to be applied to overcome its inertia. Newton stated that because of their inertia, all things continue in a state of rest or moving in a straight line unless affected by an outside force.

Michael White gives an example: “If a perfectly smooth ball was rolled along a perfectly smooth surface and there was no wind or any other force at work, the ball could, in theory, carry on rolling forever. Of course, in real life the ball would slow down and eventually stop, and that is caused by outside forces, such as friction and air currents.” Galileo, Newton’s predecessor in the field of mechanics, had studied the properties of falling objects, but no one before Newton had thought about why a force had to be applied to a stationary object in order to make it move.

A thousand years before Newton, the Greek philosopher, Leucippus, had proposed the theory of causality that “Nothing happens without a cause, but everything with a cause and by necessity.” It is an obvious statement but there was no proof or experiment. What Newton did was to explain the idea that forces need to act on an object and to cause the effect of overcoming inertia or changing the object’s path. “He proved this idea using geometry and predicted the effect caused by the application of forces of various strengths on different objects,” writes Michael. To me, Newton showed what ‘real’ science was in comparison with pseudo-scientists and the philosophies of the Greek.

Michael continues, “Newton laid down laws that could be applied to predict events with remarkable accuracy. Newton’s mechanics was systematic, it was built on sound fundamental principles and simple, irrefutable laws which could be applied to the most elaborate and complex problems – problem such as sending spaceships to the planets, or something as relatively simple as the movements of a billiard ball on a smooth surface.” These and many more of Newton’s scientific contributions to the world today. I recommend this book for sure, and all other books – biographies of great people especially – because of its inspirational and creative values.

THINK BIG. START SMALL. GO DEEP.