The spirits of the sons of the Kingdom after the disintegration of this body ascend to the world of Eternal Existence; but should you ask of the place, know thou that that world of existence is the world of unity, but the grades are different. For instance, the mineral existence has a grade, but that mineral being has no knowledge of the vegetable kingdom. It (the mineral existence) has no information of a higher realm nay, rather, according to appearances, it may deny the higher grade. Likewise the vegetable life has no knowledge of the animal kingdom. It is entirely heedless and unconscious of that kingdom, because the grade of the animal is higher than that of the vegetable. The vegetable, according to its limited environment, is veiled from the knowledge of the animal kingdom, and it may deny it, although the animal, the vegetable and mineral live in the world of existence. Likewise, the animal cannot comprehend the intelligence of the faculties of man, which is the generalizer of the universal and the discoverer of the mysteries of beings, so much so that while living in the East he organizes and founds institutions in the West, and he reveals hidden things. Though he abides in Europe he discovers America. Though he dwells upon the earth, he unravels the realities of the solar system. The animal is entirely unconscious, nay, rather, a denier of this intelligent force, which penetrates into the unknown and comprehends the general as well as the particular ideas of this illimitable universe.
Likewise the people of the world lack the knowledge of the world of the Kingdom, nay, rather, they deny it. Do we not hear from their lips the words, such as these: "Where is the Kingdom? Where is the Lord of the Kingdom?" But these souls are like unto the mineral and vegetable who know nothing of the animal and human kingdoms. They neither see nor search. However, the mineral, the vegetable and the animal kingdoms all live in this world of existence.
- ‘Abdu’l-Baha (From a Tablet, Star of the West, vol. 2, no. 5, June 5, 1911)