Whatever we fill our minds with, that is what we become. Our thoughts determine our pleasantness or unpleasantness; our social skills or clumsy communications; violent habits or docile ones; success in marriage and in our profession or dismal failure. It all depends on how we constitute and reconstitute our minds, not daily, but moment to moment. Happiness or suffering, success or failure, is not created by others, but by ourselves.
The mind is an energy field. Just as an energy field may be weak or strong, a particular mind-field may be weak or strong. A weak energy field may be strengthened through the application of appropriate technology. A weakened mind may be strengthened through the application of certain methods: self-experimentation in mental, vocal, and physical behaviour; self-observation; concentration; and meditation.
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