It is evident that every age in which a Manifestation of God hath lived is divinely ordained, and may, in a sense, be characterized as God’s appointed Day. This Day, however, is unique, and is to be distinguished from those that have preceded it. The designation “Seal of the Prophets” fully revealeth its high station. The Prophetic Cycle hath, verily, ended. The Eternal Truth is now come. He hath lifted up the Ensign of Power, and is now shedding upon the world the unclouded splendor of His Revelation.
Baha’u’llah, Gleanings XXV
In man five outer powers exist, which are the agents of perception—that is to say, through these five powers man perceives material beings. These are sight, which perceives visible forms; hearing, which perceives audible sounds; smell, which perceives odors; taste, which perceives foods; and feeling, which is in all parts of the body and perceives tangible things. These five powers perceive outward existences.
Man has also spiritual powers: imagination, which conceives things; thought, which reflects upon realities; comprehension, which comprehends realities; memory, which retains whatever man imagines, thinks and comprehends. The intermediary be- tween the five outward powers and the inward powers is the sense which they possess in common—that is to say, the sense which acts between the outer and inner powers, conveys to the inward powers whatever the outer powers discern. It is termed the common faculty, because it communicates between the out- ward and inward powers and thus is common to the outward and inward powers.
For instance, sight is one of the outer powers; it sees and perceives this flower, and conveys this perception to the inner power—the common faculty—which transmits this perception to the power of imagination, which in its turn conceives and forms this image and transmits it to the power of thought; the power of thought reflects and, having grasped the reality, conveys it to the power of comprehension; the comprehension, when it has comprehended it, delivers the image of the object perceived to the memory, and the memory keeps it in its repository.
The outward powers are five: the power of sight, of hearing, of taste, of smell and of feeling.
The inner powers are also five: the common faculty, and the powers of imagination, thought, comprehension and memory.
Abdu’l-Baha’, Some Answered Questions Part 4, Section 56