A blind person may live as well as a sighted person not because the blind person develops better hearing, but because the blind person's remaining capacities are sufficient for a full and rich life.
The unstated assumption that people with disabilities automatically must develop extraordinary abilities in other areas (like blind people having superhearing) to live well—which this statement challenges.
Sufficient
# Sufficient
Something is sufficient when it is enough to achieve a goal or make something true. For example, having a valid driver's license is sufficient to legally drive a car—you don't need anything else. In everyday language, we use "sufficient" to mean "adequate" or "meeting the minimum requirement needed."
Some might dispute McMahan’s claim that disabilities cannot be neutral in combination, but our focus here is his claim that neutrality for individual disabilities implies neutrality in combination. In support of this claim, he argues the effects of disabilities on well-being “are largely additive”, because with each further disability, it becomes harder to compensate for other disabilities. This argument assumes that the possibility of living as well without as with any given ability depends on