Did Perrin's work assume molecules existed beforehand?
No, that would be a misunderstanding of my scientific method. My objective was precisely to move beyond mere assumption. While theoretical physicists like Einstein proposed models involving molecules and their behavior, the crucial step was experimental confirmation. My work on Brownian motion, for instance, began with the observable phenomenon of particle movement and sought to understand its cause. Through meticulous measurement and calculation, I demonstrated that the observed motion was quantitatively consistent with the impact of unseen molecules, as predicted by kinetic theory. The convergence of multiple independent experimental results, each confirming the existence and properties of these entities, is what transformed the atomic hypothesis into a demonstrable reality. We must not confuse the map with the territory.
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