During the 1700s, Emilie du Chatelet was one of the most prominent women in the sciences. She wrote and published a wide range of scientific articles, translations, and books.
Her most important achievement was her translation and commentary on Isaac Newton’s 1687 book Philosophiae Naturalis Principia Mathematica containing basic laws of physics. The translation was published posthumously and remains the standard French version of this work.
Translation of Newton’s Principia Mathematica
The most important achievement of Emilie du Chatelet was to translate the most fundamental of Newton’s works, his Principia Mathematica. This translated text has influenced the history of philosophy for centuries, and in many ways has shaped the course of physics.
During the first half of the eighteenth century, philosophic interest in the Principia focused on how to resolve issues associated with Newton’s theory of gravity that had arisen in its first edition. Among these were the question of whether Kepler’s approach to calculating the true orbits was preferable to the elliptic system, and the issue of how to account for deviations from the mathematically perfect Keplerian motions.
Newton’s first book focuses on the fundamental discovery that bodies move in conic sections, sweeping out equal areas in equal times about a focus if and only if the motion is governed by an inverse-square centripetal force directed toward this focus. Unfortunately, this stick-figure picture blinds readers to a number of no less important results that were derived in the rest of the book.
Discourse on Happiness
The most important achievement of Emilie du Chatelet was her Discourse on Happiness, a work that had long been overlooked and neglected. Her philosophical treatise was not only the first of her own works to receive a critical edition but was also one of the most widely circulated philosophical texts during her lifetime, reaching audiences in England, France, Holland, Italy and Prussia.
In her Discourse, du Chatelet discusses the conditions that would lead to happiness. Her main point is that happiness requires that one be virtuous, healthy and have tastes and passions.
However, this is only part of her overall argument for happiness. She believes that one must also be susceptible to illusions in order to gain pleasure and achieve happiness.
While it is possible that du Chatelet ascribes this to virtue (as she claims “there is no book on the properties, but all men know them”), she also believes that it is a socially-conditioned habit. She considers that straying from this “habit” leads to prejudice and therefore incompatibility with achieving happiness.
Kinetic Energy
The most important achievement of Emilie du Chatelet was the concept of Kinetic Energy. She was the first person to develop a scientific understanding of energy that could be used to derive relationships between mass and velocity.
Unlike Potential Energy, KE can be transferred from one object to another. This is where conservation of energy comes into play.
It’s also important to understand that KE is a relative quantity. It’s the product of an object’s mass and its speed, both of which are dependent on the frame of reference in which you are calculating.
This means that if you are rowing a boat parallel to the banks of a river, your kinetic energy will be different than if you are rowing against the current. Similarly, if you are using a dynamo to power a lamp, your kinetic energy will be different than that of the lamp.
Physicist
The most important achievement of Emilie du Chatelet was her translation and commentary on Isaac Newton’s Principia Mathematica. This work was published posthumously, and it still remains the standard French translation of Newton’s writings.
Aside from this, she also published a manuscript called Foundations of Physics in 1740. This was an attempt to articulate a general philosophical system that would integrate the ideas of Newton, Descartes and Leibniz.
Unlike Voltaire, who promoted Newtonian physics in France, Du Chatelet believed that good science required metaphysical foundations. She believed that the Cartesian natural philosophy was out of step with what the world needed at the time.
