Your thought experiment is a bad approach because the underlying premise is that moral judgments and legal standards should be determined by subjective reactions rather than objective realities. Trying to define a person by considering our feelings about whether the baby is "alive enough" is part of how we got into this abortion morass in the first place. Yes, we should agree on a definition of a person, but not according to how we feel about babies in the womb. Objective, not subjective.
Your thought experiment is a bad approach because the underlying premise is that moral judgments and legal standards should be determined by subjective reactions rather than objective realities. Trying to define a person by considering our feelings about whether the baby is "alive enough" is part of how we got into this abortion morass in the first place. Yes, we should agree on a definition of a person, but not according to how we feel about babies in the womb. Objective, not subjective.