…human knowledge is of two
kinds. One is the knowledge of things perceptible to the senses—that is to say,
things which the eye, or ear, or smell, or taste, or touch can perceive, which
are called objective or sensible. So the sun, because it can be seen, is said
to be objective; and in the same way sounds are sensible because the ear hears
them; perfumes are sensible because they can be inhaled and the sense of smell
perceives them; foods are sensible because the palate perceives their
sweetness, sourness or saltness; heat and cold are sensible because the
feelings perceive them. These are said to be sensible realities.
The other kind of human
knowledge is intellectual—that is to say, it is a reality of the intellect; it
has no outward form and no place and is not perceptible to the senses. For
example, the power of intellect is not sensible; none of the inner qualities of
man is a sensible thing; on the contrary, they are intellectual realities. So
love is a mental reality and not sensible; for this reality the ear does not
hear, the eye does not see, the smell does not perceive, the taste does not
discern, the touch does not feel. Even ethereal matter,
the forces of which are said in physics to be heat, light, electricity and
magnetism, is an intellectual reality, and is not sensible. In the same way,
nature, also, in its essence is an intellectual reality and is not sensible;
the human spirit is an intellectual, not sensible reality. In explaining these
intellectual realities, one is obliged to express them by sensible figures
because in exterior existence there is nothing that is not material. Therefore,
to explain the reality of the spirit—its condition, its station—one is obliged
to give explanations under the forms of sensible things because in the external
world all that exists is sensible. For example, grief and happiness are
intellectual things; when you wish to express those spiritual qualities you
say: “My heart is oppressed; my heart is dilated,” though the heart of man is
neither oppressed nor dilated. This is an intellectual or spiritual state, to
explain which you are obliged to have recourse to sensible figures.
(‘Abdu’l-Baha, table talks in Akka, authenticated by
‘Abdu’l-Baha; ‘Some Answered Questions’)
