i don't know. so the one principle i try to enact & embody at all times is: humility. try to do good; but act always knowing you could be wrong.
because i don't know what is true. i don't know where i would look, what i would do, to find what is true. is the bible true? the quran? dialectical materialism? billions of people will say: "the truth is simple, look here!" but if it were that simple then everyone would agree; or at least, the ones who are right, among themselves they would live in harmony and show us by their *actions* that they are right. but they don't! so i don't think they know either.
and if you look at all the horrible, evil things that have been done throughout recorded history: the holocaust; the enslavement of africans by europeans; the enslavement of women by men; the murder of millions of people and the destruction of millennia of culture and history by christian or muslim conquerors; the annihilation of beautiful irreplaceable nature by petty plutocrats -- all of these evils are done by people who say, "we know we are right! we have the right! how dare you think we are not right! look at everyone who agrees!" and if you read what eichmann said, when they put him on trial in jerusalem: he was so sure he was right; even afterwards, he would swear he was right.
these people wrote books and made speeches about how they were right, that now no one reads, because we know they were wrong. but the person who thinks, "i may be wrong"? that person doesn't kill, doesn't rape, doesn't destroy, because to that person, their imaginary reasons are less real than what they would be destroying. which is how it should be. so my morality, to sum it up in one word, is humility.