Full Idea
His view of elements allowed Mendeleev to maintain the validity of the periodic table even in instances where observational evidence seemed to point against it.
Gist of Idea
Mendeleev had a view of elements which allowed him to overlook some conflicting observations
Source
Dmitri Mendeleev (The Principles of Chemistry [1870]), quoted by Eric R. Scerri - The Periodic Table 04 'Making'
Book Reference
Scerri,Eric R.: 'The Periodic Table' [OUP 2007], p.118
A Reaction
Mendeleev seems to have focused on abstract essences of elements, rather than on the simplest substances they had so far managed to isolate.
Related Idea
Idea 17400 Mendeleev focused on abstract elements, not simple substances, so he got to their essence [Mendeleev, by Scerri]