Full Idea
Unlike in physics, chemical reasoning does not generally proceed unambiguously from general principles. It is a more inductive science in which large amounts of observational data must be carefully weighed.
Gist of Idea
Chemistry does not work from general principles, but by careful induction from large amounts of data
Source
Eric R. Scerri (The Periodic Table [2007], 05 'Mendel')
Book Reference
Scerri,Eric R.: 'The Periodic Table' [OUP 2007], p.142
A Reaction
This is why essentialist thinking was important for Mendeleev, because it kept his focus on the core facts beneath the messy and incomplete data.
Related Idea
Idea 17400 Mendeleev focused on abstract elements, not simple substances, so he got to their essence [Mendeleev, by Scerri]