The Collected Works of Immanuel Kant

A modern translation of Kant's first published work Thoughts on the True Estimation of Living Forces (original German "Gedanken von der wahren Schätzung der lebendigen Kräfte"). This work is Kant's first published book. It is a proposal for a new understanding of living forces, distinct from the traditional Cartesian and Leibnizian views. Kant levies a critique of the undue reverence for historical scientific figures and an advocacy for independent reasoning. Newton and Leibniz at this time were revered as nearly Saints, and Kant criticizes this tendency to revere personalities when we should be thinking completely independent of individuals. Vis viva, Vis activa and Vis motrix are all variations of the Living Force, a Leibnizian version of momentum, or "energy in movement". The critical difference between Leibniz and Newton's conception is that Leibniz squared his formula as mv^{2} instead of vectoring this formula. René Descartes kept this basic conserved quantity as scalar, but Isaac Newton correctly kept momentum vectored. In other words, Newton brilliantly deducted that it was the concept of force, not the concept of energy, that governs momentum. "Living Force" was synonymous for energy up until the 19th century. Here in the 19th century, Kant tried to assert himself into the debate over these "true" basic mechanical forces, writing letters to leading scientists Euler and Maupertuis, and writing the essay Thoughts on the True Appreciation of Living Forces. Kant argues that the nature of the essential forces can be proven by Metaphysical arguments, criticizing the Rationalist and the Empiricist schools of thoughts. He criticized the Leibniz school for not thinking beyond Sense Perception, and the Rationalists in the Wolff school for denying the very existence of an essential force.

For Thoughts on the True Estimation of Living Forces, this Reader's Edition contains an Afterword by the translator, a timeline of Kant's life and works, and a helpful index of Kant's key concepts and intellectual rivals. This edition presents Thoughts on the True Estimation of Living Forces in readable modern English and removes academic footnotes so that Kant's argument remains the primary focus.

This work marks the precocious twenty one year old student's ambitious entry into the contentious vis viva debate that had divided Cartesians and Leibnizians over the proper measure of force in moving bodies: whether force should be quantified as mv (momentum, as Descartes maintained) or mv² (living force, as Leibniz argued). Written between 1744 to 1746 but not published until 1749 due to financial constraints following his father's death, this treatise sought to mediate the dispute by arguing that essential forces in bodies could be proven through metaphysical rather than merely empirical arguments. Though Kant's resolution failed to settle the controversy and many of his distinctive claims were rejected, the text reveals his early commitment to independent reasoning over reverence for scientific authority and provides understanding into his pre critical metaphysical dualism, showing how the young Kant positioned himself between rationalist and empiricist camps while maintaining allegiance to Leibniz's conception of vis activa.