Special attention must be given to al-Farabi's treatment of the soul's imaginative faculty, which is essential to his interpretation of prophethood and prophetic knowledge. In addition to its ability to retain and manipulate sensible images of objects, he gives the imagination the function of imitation. By this he means the capacity to represent an object with an image other than its own. In other words, to imitate "x" is to imagine "x" by associating it with sensible qualities that do not describe its own appearance. This extends the representative ability of the imagination beyond sensible forms and to include temperaments, emotions, desires and even immaterial intelligibles or abstract universals, as happens when, for example, one associates "evil" with "darkness". The Prophet, in addition to his own intellectual capacity, has a very strong imaginative faculty, which allows him to receive an overflow of intelligibles from the agent intellect (the tenth intellect in the emanational cosmology). These intelligibles are then associated with symbols and images, which allow him to communicate abstract truths in a way that can be understood by ordinary people. Therefore what makes prophetic knowledge unique is not its content, which is also accessible to philosophers through demonstration and intellection, but rather the form that it is given by the prophet's imagination.