When our minds are disturbed by anger, attachment, selfishness or greed, our energies likewise get disturbed. We feel uneasy; our minds aren’t calm; our thoughts run wild. We say and do things that we later regret. If we notice a sudden disturbance in our minds and energies, we can be sure that it’s the work of some disturbing emotion. The trick is to catch it as soon as it appears and apply some opponent mental state, such as love and compassion, to avoid the problems we’d create if we give in to the troublemaking emotion and act it out. – Dr Alexander Berzin
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A Buddhist's Journey 