Principalist approach

By taking the physical principles out of chemists analytic control, Stahl made it possible for them to maintain the principalist approach to chemical composition and reaction. Compounds partook of the... 

With a new conception of chemical affinity and constitution, Berthollet moved away from his earlier principalist approach to composition. This move had consequences for his theory of acidity. He could no longer define acidity or alkalinity in terms of quality-bearing principles such as oxygen and hydrogen. Instead, he invoked the predominating or characteristic affinities to account for their peculiar behavior. Acids and alkalis were now defined by their operational characteristics, which were similar to Fourcroy s earlier conception of affinities ... 

This ideal provided the prototype of what historians have discerned in the Chemical Revolution as the principalist approach to chemical composition. See H. E. LeGrand, The Conversion of C.-L. Berthollet to Lavoisier s Chemistry, Ambix 22, 1975, 58-70, at 58. 

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