The advance of intelligence diminished, as a secondary consequence, the possible in a realm which appeared foreign to intelligence: that of inner experience.
To say diminished is even to say too little. The development of intelligence leads to a drying up of life which, in return, has narrowed intelligence. It is only if I state this principle: inner experience itself is authority that I emerge from this impotence.

p. 8 - L'Expérience Intérieure (1943)