 Part of the reason the person-based intuition has been so attractive is its good fit with what Jeff McMahan calls the Asymmetry (McMahan 1981; 2009). According to the Asymmetry, it is wrong (and makes an outcome morally worse) to bring a miserable child – a child whose life is less than worth living – into existence but it is perfectly permissible (and does not make an outcome worse) to leave the happy child out of existence. While (arguably) leaving the happy child out of existence makes things worse for that child, the person-based intuition requires for wrongdoing not that things be made worse for a person who never exists but rather that things be made worse for a person who does or will exist.