NOT WHAT YOU KNOW TO BE TRUE, WHAT YOU PROVE TO BE TRUE

"In thinking, if a person begins with certainties, they shall end in doubts, but if they can begin with doubts, they will end in certainties."

Francis Bacon (1561-1626) British statesman/philosopher.

Excellent basis for planning.

In the beginning, accept nothing as truth, test all assumptions moving to rather than starting at conclusions.

Do that and your plan will be more based on truth than not.