Full Idea
We can find the ground of a pure conceptual truth only in other conceptual truths.
Gist of Idea
The ground of a pure conceptual truth is only in other conceptual truths
Source
Bernard Bolzano (Theory of Science (Wissenschaftslehre, 4 vols) [1837], Pref)
A Reaction
Elsewhere he insists that these grounds must be in 'truths', and not just in the attributes of the concepts of involved. This conflicts with Kit Fine's view, that the concepts themselves are the source of conceptual truth and necessity.