Full Idea
If we try to base determinate reference on natural causal connection, Putnam says this is just more theory, as subject as any theory to overabundant, conflicting intended interpretations.
Gist of Idea
If we try to cure the abundance of theories with causal links, this is 'just more theory'
Source
report of Hilary Putnam (Reason, Truth and History [1981]) by David Lewis - Putnam's Paradox 'Why Are'
Book Reference
Lewis,David: 'Papers in Metaphysics and Epistemology' [CUP 1999], p.73
A Reaction
This is the 1981 Putnam, moving away from the realism that was implicit in the original causal theory of reference developed by himself and Kripke. His 'just more theory' is the slogan of Putnam's later anti-realism.