Walpola Rahula
Author: Walpola Rahula
Publisher: Grove Press (1974)

Do not be led by reports, or tradition or hearsay. Be not led by the authority of religious texts, nor by mere logic or inference, nor by considering appearances, nor by the delight in speculative opinions, nor by seeming possibilities, nor by the idea: 'this is our teacher.'  But when you know for yourself that certain things are unwholesome, and wrong, and bad, then give them up.  And when you know for yourself that certain things are wholesome and good, then accept them and follow them.