By materialists, whose belief with regard to Divinity hath been explained, is not meant philosophers in general, but rather that group of materialists of narrow vision who worship that which is sensed, who depend upon the five senses only, and whose criterion of knowledge is limited to that which can be perceived by the senses. All that can be sensed is to them real, whilst whatever falleth not under the power of the senses is either unreal or doubtful. The existence of the Deity they regard as wholly doubtful (2:3)

It is as thou hast written, not philosophers in general but narrow-minded materialists that are meant. As to deistic philosophers, such as Socrates, Plato and Aristotle, they are indeed worthy of esteem and of the highest praise, for they have rendered distinguished services to mankind. In like manner we regard the materialistic, accomplished, moderate philosophers, who have been of service (to mankind). (2:4)

We regard knowledge and wisdom as the foundation of the progress of mankind, and extol philosophers who are endowed with broad vision. Peruse carefully the San Francisco University Journal that the truth may be revealed to thee (2:5)

End of Quote

Letter to Dr. Forel
'Abdu'l-Baha