Those who call themselves "pure mystics" because they will not "adulterate" mysticism with rational, practical, altruistic, and other activities naturally adopt a contemptuous attitude toward philosophical teaching. This often happens because they are not usually conscious of the intellectual and demonistic pitfalls which beset their journey. Therefore we protest against such a partial view. Those who are sincere but lack judgement will not be saved by their sincerity alone from the sufferings into which their errors may lead them. If this, the practical reason were the only one for adding a philosophical background it would surely be enough. The mystics who throw away the use of reason, throw away one of the chief tools which Nature has given them to adjust themselves successfully to their environment. It is strange how they are so shy of this fact and actually flee from it. It is only in the hard school of bitter experience that their hallucinations may begin to fade. Those who use their mysticism to become confirmed in their foolishness are welcome to do so. But not all of us can afford to do so. Life's leaden tread sooner or later comes down on the foolish and makes them suffer for the unwisdom of their deeds. It is not an accident but a consequence that misty vagueness prevails in such circles whereas definite clarity prevails in the philosophical ones. Spiritual progress may free itself from these delusions and dangers only on the basis of a clear understanding of what spirituality really means.
-- Notebooks Category 16: The Sensitives > Chapter 2 : Phases of Mystical Development > # 158