One cannot validly argue that humans are morally superior beings on the ground that they possess, while others lack, the capacities of a moral agent. The reason is that, as far as moral standards are concerned, only beings that have the capacities of a moral agent can meaningfully be said to be either morally good or morally bad. Only moral agents can be judged to be morally better or worse than others, and the others in question must be moral agents themselves. Judgments of moral superiority are based on the comparative merits or deficiencies of the entities being judged, and these merits and deficiencies are all moral ones, that is, ones determined by moral standards. One entity is correctly judged morally superior to another if it is the case that, when valid moral standards are applied to both entities, the first fulfills them to a greater degree than the second. Both entities, therefore, must fall within the range of application of moral standards. This would not be the case, however, if humans were being judged superior to animals and plants, since the latter are not moral agents.