"The attainment of any object is conditioned upon knowledge, volition and action."

"All the heavenly Books, divine Prophets, sages and philosophers agree that warfare is destructive to human development, and peace constructive. They agree that war and strife strike at the foundations of humanity. Therefore, a power is needed to prevent war and to proclaim and establish the oneness of humanity.

But knowledge of the need of this power is not sufficient. Realizing that wealth is desirable is not becoming wealthy. The admission that scientific attainment is praiseworthy does not confer scientific knowledge. Acknowledgment of the excellence of honor does not make a man honorable. Knowledge of human conditions and the needed remedy for them is not the cause of their betterment. To admit that health is good does not constitute health. A skilled physician is needed to remedy existing human conditions. As a physician is required to have complete knowledge of pathology, diagnosis, therapeutics and treatment, so this World Physician must be wise, skillful and capable before health will result. His mere knowledge is not health; it must be applied and the remedy carried out.

The attainment of any object is conditioned upon knowledge, volition and action. Unless these three conditions are forthcoming, there is no execution or accomplishment. In the erection of a house it is first necessary to know the ground, and design the house suitable for it; second, to obtain the means or funds necessary for the construction; third, actually to build it. Therefore, a power is needed to carry out and execute what is known and admitted to be the remedy for human conditions—namely, the unification of  mankind. Furthermore, it is evident that this cannot be realized through material process and means. The accomplishment of this unification cannot be through racial power, for races are different and diverse in tendencies. It cannot be through patriotic power, for nationalities are unlike. Nor can it be effected through political power since the policies of governments and nations are various. That is to say, any effort toward unification through these material means would benefit one and injure another because of unequal and individual interests. Some may believe this great remedy can be found in dogmatic insistence upon imitations and interpretations. This would likewise be without foundation and result. Therefore, it is evident that no means but an ideal means, a spiritual power, divine bestowals and the breaths of the Holy Spirit will heal this world sickness of war, dissension and discord. Nothing else is possible; nothing can be conceived of. But through spiritual means and the divine power it is possible and practicable."

`Abdu'l-Bahá, The Promulgation of Universal Peace, pp. 157-158 

30 May 1912
(excerpt from)Talk at Theosophical Lodge 
Broadway and Seventy-ninth Street, 
New York