Jeremy Stangroom has posted a nice exchange of letters from 1959 between Bertrand Russell and Lord Russell of Liverpool. It concerns the fact that some people were getting the two of them mixed up. The exchange led to a joint letter to The Times, as follows:
Sir,- In order to discourage confusions which have been constantly occurring, we beg herewith to state that neither of us is the other.
Russell (Bertrand, Earl Russell)
Russell of Liverpool (Lord Russell of Liverpool)
I did contemplate suggesting that, so far from neither being the other, both are in fact the other, since each is an other to the other one; but I have thought better of it.