CAPACITY (δύναμις).— (1) Potentiality or capability, Aristotle distinguishes potentiality or capacity from activity; (2) Modern usage,—Receptive power. Taking the twofold view of human power, faculty is power of acting; capacity is power of receiving impression. In popular language, capacity is often used as convertible with faculty,—a man of capacity standing for a man of ability.
| «There are powers which are acquired by use, exercise, or study, which are called habits. There must be something in the constitution of the mind necessary to our being able to acquire habits, and this is commonly called capacity» (Reid; Intellectual Powers, essay I. ch. I.). |
Dr Reid did not recognise the distinction of power as active or passive. But capacity is a passive power, or natural receptivity. A faculty is a power which we are conscious we can direct towards an end. A capacity is rather a disposition or aptitude to receive certain modifications of our consciousness, in receiving which we are passive. But an original capacity, though at first passive, may be brought under the influence of will and attention, and when so exercised it corresponds to a mental power, and is no longer a pure receptivity. ‘In sensation, we are in the first instance passive, but our capacity of receiving sensations may be employed in various ways under the direction of will and attention, or personal activity.
