How did the Marburg school adapt Kantian idealism to modern physics?

The Marburg school of Neo-Kantianism, led by Hermann Cohen, adapted Kantianism by rejecting the idea that knowledge is "given" (gegeben) by external objects. Instead, they argued that the transcendental subject functions as a logical process that constructs both the form and content of knowledge.1

By applying this "logistic" approach to the exact sciences, the school sought to ground scientific understanding in the logical spirit of human thought rather than in raw sensory data. Cohen utilized the infinitesimal calculus as a primary model, illustrating how the mind generates concepts—such as motion—by imagining and synthesizing mathematical abstractions like thin slices of space and time.1

This methodology allowed the Marburg school to move away from the physiological naturalism of thinkers like Hermann von Helmholtz, instead emphasizing that scientific reality is a "propounded" (aufgegeben) construction of the logical intellect. Figures such as Paul Natorp and Ernst Cassirer further integrated this transcendentalism into the foundations of the exact sciences and the broader history of modern philosophy.12