Full Idea
There may be a causal chain from our use of the term 'Santa Claus' to a certain historical saint, but still children, when they use this, by this time probably do not refer to that saint.
Gist of Idea
We may refer through a causal chain, but still change what is referred to
Source
Saul A. Kripke (Naming and Necessity lectures [1970], Lecture 2)
Book Reference
Kripke,Saul: 'Naming and Necessity' [Blackwell 1980], p.93
A Reaction
This is quite a significant concession to critics of the causal theory. I take it that community agreement is much more significant for reference than the actual causal chain, which may be riddled with errors from beginning to end, and so isn't causal.