Locke examines the relationship between mind and matter, reality and value. “We need to consider what 'person' means. I think he is an intelligent thinking being, who has reason and reflection, and can regard himself as himself, the same thinking thing in different times and places” (Locke, 115). If we consider what “person” represents, then we may want to exclude the original meaning of the word, the term person means to exclude many human beings. For the ancient Romans, only elite men counted as people, meaning that women, slaves and children were not included. Regan's theory replaces Locke's by attributing value to all life, not just intelligent and rational beings. A human being can be classified as an animal, but what makes us different is the mind, we are capable of empathy. “Consciousness always accompanies thought and causes everyone to be what it calls 'self' and therefore distinguishes itself from all other thinking things; in this alone does personal identity consist" (Locke, 115). Locke states that since we are conscious of the act of thinking we cannot be animals because animals act according to instinct. An example of this is that when an animal is kicked, they react immediately, but when a person is kicked, they analyze and process the situation