The second doctrine of the Perennial Philosophy — that it is possible to know the Divine Ground by a direct intuition higher than discursive reasoning — is to be found in all the great religions of the world. A philosopher who is content merely to know about the ultimate Reality — theoretically and by hearsay — is compared by Buddha to a herdsman of other men's cows. Mohammed uses an even homelier barnyard metaphor. For him the philosopher who has not realized his metaphysics is just an ass bearing a load of books. Christian, Hindu, Taoist teachers wrote no less emphatically about the absurd pretensions of mere learning and analytic reasoning.

Introduction to the Bhagavad-Gita (1944)