let λxϕ(the ζ) represent a sentence of English containing a definite description the ζ in an extensional position.2 Then the truth conditions of λxϕ(the ζ) are correctly stated by Russell’s theory; i.e. it is true at a world w iff there is exactly one object u which satisfies ζ in w and λxϕ is true of u in w.
Klein, E. (1981)., Defensible descriptions, in F. Heny (ed.), Ambiguities in intensional contexts, Dordrecht, Springer, pp. 83-102.
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