Do unto others as you'd have them do unto you is an example of a credo.
Other Word Forms
Origin of credo
- Middle English the Apostles' Creed from Latin crēdō I believe (the first word of the Apostles' Creed or the Nicene Creed) first person sing. present tense of crēdere to believe kerd- in Indo-European roots
From American Heritage Dictionary of the English Language, 5th Edition