Can a non-human animal be a person?

Have you ever talked about your pet as if they were a member of the family? Even if you have not, this is a common behaviour in those who share their lives with a non-human animal. However, even if non-human animals play a large role in their human's life, the status of their personhood -or lack of it- can still be debated. Carl Safina tackles the ambiguity surrounding the issue of what a person actually is, by writing that what a person is, and consequently whether or not your pet can be classified as one, should not be determined by whether or not they behaviour like a human. This, she deems, is 'speciesist', or expressing an unjust preference for the human species. Instead, she writes that whether or not an animal is to be classed a person should be based on the answer to the question, 'Do they value their lives?'. The answer, she supposes, is 'yes'. Following this line of thought, not only would your dog or cat count as a person, but so would many, if not all other species of animal. While this can appear a conclusive answer on whether or not a non-human animal can be classified as a person, I would suggest looking into Peter Kreeft's argument against functionalism for another perspective.