Man has two powers; and his development, two aspects. One
power is connected with the material world, and by it he is capable of material
advancement. The other power is spiritual, and through its development his
inner, potential nature is awakened. These powers are like two wings. Both must
be developed, for flight is impossible with one wing.
- ‘Abdu’l-Baha (From a talk,
25 April, 1912, Washington, D.C.; ‘The Promulgation of Universal Peace: Talks
Delivered by 'Abdu'l-Bahá during His Visit to the United States and Canada in
1912’)
