For me, this act communicates a message about good intentions going out into the world to bear fruits, even when it seems that the line of efficient cause has been swept away and the immediate situation completely muddied. Even though the pains-takingly created form of the mandala has been destroyed, it still has the capacity to carry a blessing into the world. It's as if the exercise of creating the mandala was principally about creating a focus for goodwill and samadhi, and only secondarily about achieving a certain preconceived specific 'result'.
This is the opposite of the mindset of most of the manager/politician types who try to control and shape civilisation. In my opinion, it would be better if they faced contingencies in the present with simple goodwill and skill, instead of imposing fixed rules, targets and ideologies.
I also reminded of the story of the tender-hearted bird that tries to put out a forest-fire with the drops of water it can carry from the lake in its feathers. It's a kind of compassionate implacability.
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