“The question is not, Can they reason? nor, Can they talk? but, Can they suffer?”
Bentham shifts the basis for moral consideration of animals away from intelligence or speech and toward the capacity to experience suffering.
Source details
An Introduction to the Principles of Morals and Legislation, Chapter XVII, section 1 footnote, reviewed against the represented Liberty Fund text. Bentham's 'Can they suffer?' question appears in his argument that sentience, not species membership or speech, is morally relevant to cruelty; it remains historical utilitarian philosophy rather than current legal doctrine.