Psilocybin use leads to increase in openness

Although the study below has been published a few years ago, I'm referencing it now as a result of re-reading Chapter 16 of Lao Tzu's Tao Te Ching translated by Witter Bynner*:

Be utterly humble
And you shall hold to the foundation of peace, 
Be at one with all those living things which, having arisen and flourished,
Return to the quiet whence they came,
Like a healthy growth of vegetation
Falling back upon the root,
Acceptance of this return to the root has been called 'quietism,'
Acceptance of quietism has been condemned as 'fatalism,'
But fatalism is acceptance of destiny
And to accept destiny is to face life with open eyes,
Whereas not to accept destiny is to face death blindfolded,
He who is open-eyed is open-minded,
He who is open-minded is open-hearted,
He who is open-hearted is kingly,
He who is kingly is godly,
He who is godly is useful,
He who is useful is infinite,
He who is infinite is immune,
He who is immune is immortal. 
   *A gift to me from Brian Simpson in 1994

Mystical experiences occasioned by the hallucinogen psilocybin lead to increases in the personality domain of openness. (PDF)
MacLean KA, Johnson MW, Griffiths RR. J Psychopharmacol. 2011 Nov;25(11):1453-61. Epub 2011 Sep 28. 
PMID: 21956378
Abstract 
A large body of evidence, including longitudinal analyses of personality change, suggests that core personality traits are predominantly stable after age 30. To our knowledge, no study has demonstrated changes in personality in healthy adults after an experimentally manipulated discrete event. Intriguingly, double-blind controlled studies have shown that the classic hallucinogen psilocybin occasions personally and spiritually significant mystical experiences that predict long-term changes in behaviors, attitudes and values. In the present report we assessed the effect of psilocybin on changes in the five broad domains of personality - Neuroticism, Extroversion, Openness, Agreeableness, and Conscientiousness. Consistent with participant claims of hallucinogen-occasioned increases in aesthetic appreciation, imagination, and creativity, we found significant increases in Openness following a high-dose psilocybin session. In participants who had mystical experiences during their psilocybin session, Openness remained significantly higher than baseline more than 1 year after the session. The findings suggest a specific role for psilocybin and mystical-type experiences in adult personality change.
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