How did Claude Bernard argue that experimental physiology could improve medicine?

Claude Bernard argued that for medicine to progress, it must be firmly established on the foundation of experimental physiology. In his seminal work, An Introduction to the Study of Experimental Medicine, he outlined several key arguments to support this transition:1

• Scientific Foundation: He asserted that physiology relies on the physical and chemical sciences, though it cannot be entirely reduced to them.1
• Mechanistic Determination: He argued that biology must recognize that life processes are determined by physico-chemical forces, rejecting the notion that a vague "vital force" can explain life.1
• Methodological Rigor: Bernard moved away from purely empirical observation, demonstrating that an experimenter requires a guiding hypothesis to be either confirmed or refuted by results.1
• Research Necessity: He maintained that vivisection is an indispensable tool for physiological research.1

By shifting the focus toward these experimental principles, Bernard helped move the field beyond earlier indeterminism, ultimately establishing the concept of the internal environment, or milieu intérieur, which remains central to our modern understanding of homeostasis.21