Energy and concentration work just the same way: they must both be strong but must also be in balance. When energy is deficient there is sloth, torpor, dullness, and tiredness. When energy is in excess the mind and body may be restless, jumpy, strained, and irritable. It may even be unable to focus at all because so much emphasis is being placed on effort itself. When concentration is deficient the mind won't stay with an object and tends to get lost in thought. When concentration is in excess one can get lost in one's objects or be focused too narrowly and tightly for reality to “breathe.”
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