Final answer:
Mattingly argues that people use "moral laboratories" as spaces where they learn, reflect, and develop their moral thinking and values.
Step-by-step explanation:
Mattingly argues that people use "moral laboratories" to shape their sense of ethics. By this, she means that individuals engage in various experiences and interactions with others and societal institutions, which influence their moral beliefs and behaviors. These "moral laboratories" serve as spaces where individuals learn, reflect, and develop their moral thinking and values.