 The challenges to the structural view of bonding have engendered several responses in the philosophical and chemical literatures. The first appeals to chemical practice: Chemists engaged in synthetic and analytic activities rely on the structural conception of bonding. There are well over 100,000,000 compounds that have been discovered or synthesized, all of which have been formally characterized. How can this success be explained if a central chemical concept such as the structural conception of the bond does not pick out anything real in nature?  Throughout his life, Linus Pauling (1901–1994) defended this view.