One basic truth of the human mind that the Buddha pointed to very often is that wisdom and compassion are inseparable. In one of the traditional similes there is the giant bird, the great eagle with two wings, one wing of which is wisdom and the other is compassion. The Buddha pointed out that the more clearly we see the nature of suffering, the more clearly we understand that suffering is conditioned by desire born of ignorance; we see the efficacy of the Eightfold Path in alleviating that suffering, and we begin to see cessation. As our understanding of the Four Noble Truths deepens, we feel more compassion for ourselves and for others – indeed for all sentient beings. So the test, if you like, of the wisdom that we have developed through our practice is the amount of compassion there is, and a test of the compassion in our heart – knowing whether it's true compassion, and not mere pity or sentimentalism – is the wisdom faculty.
Where there is true wisdom there is compassion, where there is true compassion there is wisdom. But if compassion lacks wisdom it can do more harm than good. There is an old English saying: `The road to hell is paved with good intentions.' Sometimes people try to do good or to help, without understanding their own mind and motivation, and without understanding the people they want to help. They have no sensitivity to time and place or to their own capacity, and so they don't achieve the results that they hope for. Then they can become angry, disillusioned or offended and if there is any criticism, such a person will feel even more hurt. They might think that the action must have been correct because it was based on a good intention, that their hearts were pure in their intention. But purity of intention is not enough, it has to be based on wisdom: understanding the nature of suffering, how it comes into existence and how it is alleviated. It has to be based on the true understanding of suffering.
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