"Say: Spirit, mind, soul, and the powers of sight and hearing are but one single reality which hath manifold expressions owing to the diversity of its instruments."

"O Pen of the Most High! Recount unto him who hath turned unto Thy Lord, the All-Glorious, that which shall enable him to dispense with the sayings of men. Say: Spirit, mind, soul, and the powers of sight and hearing are but one single reality which hath manifold expressions owing to the diversity of its instruments. As thou dost observe, man’s power to comprehend, move, speak, hear, and see all derive from this sign of his Lord within him. It is single in its essence, yet manifold through the diversity of its instruments. This, verily, is a certain truth. For example, if it directeth its attention to the means of hearing, then hearing and its attributes become manifest. Likewise, if it directeth itself to the means of vision, a different effect and attribute appear. Reflect upon this subject that thou mayest comprehend the true meaning of what hath been intended, find thyself independent of the sayings of the people, and be of them that are well assured. In like manner, when this sign of God turneth towards the brain, the head, and such means, the powers of the mind and the soul are manifested. Thy Lord, verily, is potent to do whatsoever He pleaseth."

~Bahá'u'lláh

(The Summons of the Lord of Hosts)