I would use the Golden Rule as a foundation for defining Good. Which is ironic as it's really a selfish rule as you expect like treatment for your actions.
By extension you would have the Iron Rule "Those who would deny you your rights must be resisted."
As someone previously stated, preservation is a key to defining Good, but it's the preservation of self and by extension the preservation of the group that you identify yourself with. Anything that seeks to destroy you or your identified group would be considered Evil.
Most, I think, share common definitions of Good and Evil. It would be hard to truly make a groundbreaking moral code as your audience would use their own commonly shared definition of Good as a reference and find anything significantly different as outlandish at best.
By extension you would have the Iron Rule "Those who would deny you your rights must be resisted."
As someone previously stated, preservation is a key to defining Good, but it's the preservation of self and by extension the preservation of the group that you identify yourself with. Anything that seeks to destroy you or your identified group would be considered Evil.
Most, I think, share common definitions of Good and Evil. It would be hard to truly make a groundbreaking moral code as your audience would use their own commonly shared definition of Good as a reference and find anything significantly different as outlandish at best.