Perhaps the most famous idea that Sir Isaac Newton, a seventeenth-century English scientist and writer, contributed to the scientific revolution was the theory of gravity. Newton wrote about what he called three laws of motion, which included the laws of gravity. He received a knighthood from the British monarch for his contributions to science. There is an anecdotal story about how he began to think about gravity after being struck on the head by a falling apple as he sat under an apple tree. This example is one that laymen can easily understand, although it probably did not happen to him this way.

However, the concept of an apple falling from a tree does illustrate the force of gravity that leads everything to fall back down to the earth after being tossed into the air. This in and of itself was not a breakthrough concept, as people generally knew that objects fall to earth. Moreover, decades earlier Galileo had written about the concept and experimented with objects of different sizes and different weights.

However, Isaac Newton wondered why the apples always fall back down to earth in a straight line. His thoughts and experiments led him to expand on the writings and studies of earlier scientists in order to further develop concepts of the laws of motion, including gravity. Newton developed ideas around how the law of gravity applies to all objects regardless of size or mass and posited theories about how size and mass impact their gravitational force. He also developed theories about the orbits of planets.