There is a different between being morally responsible and being morally considerable. Human beings are both. Moral responsibility implies a duty and therefore a capability to act in an ethical manner. Animals can not of course be morally responsible as they do not have the intellectual capacity to ascertain what is right and wrong, only instincts as to how to survive. We cannot expect animals to be morally responsible but this does not mean that human beings do not have a duty to be morally responsible. It would be ideal for all beings to act in an ethical manner but only humans are capable of considering ethics and therefore we are the only morally responsible beings. Moral considerability refers to whether or not a being deserves to be treated in an ethical manner. There is a burden on the proposition to show why moral considerability relies on being morally responsible. Profoundly retarded human beings and babies are unable to be morally responsible and yet we consider them to be morally considerable.