On Bertran Russell's "the Problems of Philosophy"?

Question

Can someone please explain the part where Russell uses Bismark as an example?

"But we know that there is an object B, called Bismark, and that B was an astute diplomatist. We can only describe the proposition we should like to affirm, namely, 'B was an astute diplomatist', where B is the object which was Bismarck. If we are describing Bismarck as 'the first Chancellor of the German Empire', the proposition we should like to affirm may be described as 'the proposition asserting, concerning the actual object which was the first Chancellor of the German Empire, that this object was an astute diplomatist'."

Answer 1

Russell's point here has to do with the with the priority of proper names. The two propositions aren't equivalent, one given by "Ab" (Bismark is an astute diplomat) and the other by a definite description with conjunctions and quantifiers. There are possible worlds where "Ab" arguably isn't the first chancellor of the German empire.