Most people would agree that there is a standard, or lowest common denominator of accepted beahvior, that western non religious based cultures adhere to. Without any specific published guide most people try to be polite and kind and to show a level of respect to others. As such most of us try not to be rude or disrespectful, to disrespect and break laws, to commit acts of un justified violance or to commit murder under most any circumstance. Without quoteing any religious text I believe this is a standard of morality.
