Madam, - Dr Stephen Costello (May 30th) says he is responding to Peter Singer, a "fellow philosopher", in the "spirit of dialectics"; but his letter ends up in vulgar abuse of Singer. He should ask himself what there is in the suggestion that human beings are animals to cause such a defensive reaction.
"I am an animal lover and I would never encourage unnecessary cruelty towards them," he writes. Why am I irresistibly reminded of that phrase, "Some of my best friends are. . ."? It is true that there are differences between humans and other animals, but there are also many similarities.
A philosopher needs to justify - not just propagate a selective focus. - Yours, etc.,
HILARY TOVEY, Sandymount, Dublin 4.