Mysticism, when psychologically comprehended and correctly practised, can certainly give man--weak-willed, passion-driven, and earthward-bent, as he often is--definite disciplinary, emotional, and ethical benefits. But so far as it shuts him up to lounge in his inner recesses and enjoy their peace alone, or so far as it persuades him to cast society permanently aside and withdraw like a tortoise into his own shell, it does not directly advantage others. The mystic wants to be left alone to meditate without external distractions. His peace is precious to him and he is unwilling to disturb it by sacrificing any part of his personal life for the benefit of others. The serious yogi-in-training usually spends most of a lifetime in segregation from his fellows, untrammeled by family burdens and unperturbed by social responsibility, because he is seeking something whose attainment the presence of others hinders and disturbs. He is naturally wrapped up by his discipline in a cloak of self-centeredness. Every manual of yoga which recommends the novice to turn hermit and forsake cities in moderation at the proper time in the proper place and for a limited duration, is a perfectly justifiable rule. He needs solitude and silence for the practice of his meditations. It is difficult to get these things in society so he quite properly avoids society. The very essence of all genuinely mystical exercises is the process of introversion. But carried to the point of excess, as it usually is when the practitioner is ignorant of the fact that mystic discipline is a means and not an end, it is likely to finish in callous self-centeredness. When he does not realize that asceticism is but a temporary discipline, a jumping-off ground, whence to arrive at the higher and permanent condition of internal disentanglement, he is likely to fall into the trap of making such external disentanglement the goal of life and even become callously indifferent to the well-being of others--not deliberately, of course, but as a consequence of his unbalanced introversion.
-- Notebooks Category 16: The Sensitives > Chapter 2: Phases of Mystical Development > # 120