Sri Paramahansa Yogananda, 2 : 62 - 63, God talks with Arjuna, The Bhagavad Gita.

ALL THE FOREGOING, concerning the ordinary man and his material desires, is pertinent also to the yogi and his encounters with what are sometimes more subtle entrapments. Even he who has progressed far on the spiritual path may suddenly find some sense attraction catching hold of his consciousness. Immediate action by the discrimination and self-control applied toward stronger spiritual effort and deeper meditation will save him. But allowing the mind to dwell "harmlessly" on that attraction, or to feed it in any way, is to invite the ensuing consequences. Though it may manifest more subtly, the course it takes and the spiritually destructive result are the same: sense attraction degenerating into loss of remembrance of the true Self or soul and its divine contentment, along with the loss of the guidance of discrimination that attracts the consciousness toward Spirit.

Society as a whole is also subject to degradation through the same process as individuals, who, after all, are the constituents of communities and nations. All the miseries and ghastly terrors of civilization have their roots in indiscrimination, which is the gradual ripening of the evil that sprouts unwittingly in the mind of man through the stages of attraction and attachment, longing, and desire, anger and passion, delusion and recklessness, and impropriety from loss of memory of man's true divine Self. Thus does yoga adjure man to maintain an iron grip on the thought system of his mind. Self-control must not be lost even at the greatest provocation. When evil exists within, then what appears, without is its double. He who conquers the mind, conquers the world.