In the early 90’s I was in a training class at Accenture (Andersen Consulting at the time) when this slide was shown and discussed:
It resonated with me strongly, both in terms of a way to look at our client work, and my own personal thinking/doing balance.
At SchellingPoint, where my world is groups rapidly assembling valuable, viable, and endorsed plans that get done, we use a modified version:
I hope this sentence inspires you the way it does me.