Ability, capacity, capability are often confused in use.
Ability primarily denotes the quality or character of being able (as to do or perform) and is applied chiefly to human beings.
- Everyone has the right to good medical care regardless of their ability to pay.
Capacity in its corresponding sense means the power or more especially the potentiality of receiving, holding, absorbing, or accomplishing something expressed or understood and is said of persons or things. Thus one may speak of a child’s ability to learn but not of the hall’s ability to seat 2000 persons; on the other hand, a child’s mental capacity and the hall has a seating capacity of 2000 are both acceptable.
- She has an enormous capacity for hard work.
In general, ability suggests actual power, whether native or acquired, whether exercised or not.
- A woman of her ability will easily find a job.
Capacity on the other hand stresses receptiveness, or in reference to man’s intellectual, moral, or spiritual nature, more explicitly, responsiveness, susceptibility, or aptitude.
Capacity therefore suggests potential, as distinguished from actual or, especially, manifest power.
Thus, ability to weep, the ability to work, the ability to pay, are not respectively identical in meaning with the capacity for tears, the capacity for work, the capacity for payment. The phrases of the first group mean that one can weep (because his tear glands are normal), one can work (because strong or trained), one can pay (because he has the money): those of the second group indicate, in the first case, a special sensitiveness to what is pathetic; in the second case, a readiness to work as hard as is necessary on any or every occasion; in the third case, the qualities of mind and character that promise earning power and imply a recognition of one’s obligations.
- Our capacity for giving care, love and attention is limited.
Capability is the character in a person (less often, a thing) arising from the possession of the qualities or qualifications necessary to the performance of a certain kind of work or the achievement of a given end. As applied exclusively to persons, capability may mean competence, often special competence. This connotation is usually supplied or enforced by the context.
- Age affects the range of a person’s capabilities.
- People experience differences in physical and mental capability depending on the time of day.
- Animals in the zoo have lost the capability to catch/of catching food for themselves.