One should not search for an abstract meaning of life. Everyone has his own specific vocation or mission in life to carry out a concrete assignment which demands fulfillment. Therein he cannot be replaced, nor can his life be repeated. Thus, everyone's task is as unique as is his specific opportunity to implement it.

Viktor Frankl, Man's Search for Meaning

THREE THOUGHTS CROSSED MY MIND WHEN I FIRST STARTED TO think about writing this book. One was I wish I had had the courage to have done this earlier in life. That thought opened up a line of introspection that led to my second thought: Would I be able to do justice to the innovation, the ingenuity, the bravery of the people I chose to represent the five approaches to system change ...

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