Page "Philosophiæ Naturalis Principia Mathematica" Paragraph 26

However, the concept of an attractive force acting at a distance received a cooler response.

In his notes, Newton wrote that the inverse square law arose naturally due to the structure of matter.

However, he retracted this sentence in the published version, where he stated that the motion of planets is consistent with an inverse square law, but refused to speculate on the origin of the law.

Huygens and Leibniz noted that the law was incompatible with the notion of the aether.

From a Cartesian point of view, therefore, this was a faulty theory.

Newton's defence has been adopted since by many famous physicists — he pointed out that the mathematical form of the theory had to be correct since it explained the data, and he refused to speculate further on the basic nature of gravity.

The sheer number of phenomena that could be organised by the theory was so impressive that younger " philosophers " soon adopted the methods and language of the Principia.