From pebbles to planets, tigers to tables, pine trees to people; animate and inanimate, natural and artificial; bodies are everywhere. Bodies populate the world, acting and interacting with one another, and they are the subject-matter of Newton's laws of motion. But what is a body? And how can we know how they behave? In Philosophical Mechanics in the Age of Reason, Katherine Brading and Marius Stan examine the struggle for a theory of bodies. At the beginning of the 18th century,...

The centerpiece of Émilie Du Châtelet’s philosophy of science is her Foundations of Physics, first published in 1740. The Foundations contains epistemology, metaphysics, methodology, mechanics, and physics, including such pressing issues of the time as whether there are atoms, the appropriate roles of God and of hypotheses in scientific theorizing, how (if at all) bodies are capable of acting on one another, and whether gravity is an action-at-a-distance force. Du Châtele...