Stuart Hampshire on the Inapplicability of Moral Terms to Animals and Infants

Moral terms are inapplicable to animals and infants, just because animals and infants are not language-users and do not entertain arguments or self-consciously make up their minds to act differently; we can train them and we may cause them to act in one way rather than another, but we cannot persuade them.

(Stuart Hampshire, “Freedom of the Will,” The Aristotelian Society, supplementary volume 25 [1951]: 161-78, at 165)