Newton’s Preface to Principia Mathematica

The preface of Sir Isaac Newton to Principia Mathmetica is an introduction of the book—its origin, its contents, a brief explanation of what is inside, and how the book got published. Newton explains the difference between mechanics and geometry and their relationship in the first part. On the latter part, he explains how postulations on the first part of the book may lead to calculations on the movement of celestial bodies. Finally, Newton thanks the sponsor of the book at the end.
Mechanics, Philosophy, and Geometry are words that are mentioned in frequency in the opening parts of the preface. Mechanics today would be thought of something related to machines, but back in Newton’s day, it is possibly the old name of Physics because the word “Physics” is not mentioned anywhere in the preface, and the way he describes mechanics is very much like how we see Physics today. Geometry, on the other hand, is pretty much the same way as we use it today as it was in Newton’s time, as it pertains to the study of different shapes and their measurement.
Lastly, Philosophy then was seen as more related to science, whereas today, people would not really think of science when they first hear the word “philosophy,” or at least the common person would not. The preface is divided into three parts—information about the first two books of Principia Mathematica, the third book, and then the thank you message with a disclaimer. In the first part, Newton explains the difference between geometry and mechanics and their relationship with each other.

Though there are differences, Newton states that geometry is part of mechanics and concludes that geometry is founded in mechanical as part of universal mechanics. By using geometry and mechanics, Newton aims to find out more about natural forces and explain their phenomena. The second part is about the third book. Newton states that by using the information gathered in studying geometry and mechanics, he says that movement of celestial bodies can be calculated (which is based on an already existing Kepler’s law). The third part is where Newton mentions the man who made the publication of the book possible, and that man is Mr. Edmund Halley (who was famous for calculating the return of the comet now credited to his name). Newton thanks Halley for being such a major influence in the publication of Principia Mathematica and an unfinished book about celestial movement. Finally, after crediting Halley for his efforts and influence, Newton moves on to a sort of disclaimer in the end, saying that he has put off the publication of the prospective book about celestial movement, and that delay may have caused imperfections in the current publication. As far as writing style is concerned, hints of Newton being a scientist is quite evident.
Newton attempts to keep his preface as brief and concise as possible, but there are segments in the preface where he could not let go of the urge to explain more and give more examples. To illustrate, consider as an example the latter part where he starts his “disclaimer” about not being able to publish a book and the defects found in the current book. Other than that, everything else seems very well written, especially how he alludes to the past (by mentioning ancient times) and moving to the present. It gives a sense of chronological order to his preface.