In all forms of aversion the heart contracts. We then become imprisoned by our own mind's reactions and subsequently solidify a sense of self and separation. But there is also something extremely seductive about anger that keeps pulling us in and feeding it. The Buddha described it well when he said, "Anger, with its poisoned root and honeyed tip." We feel empowered, energetic and often self-righteous when we're lost in angry feelings.
— Joseph Goldstein, One Dharma