Moral obligation and duty are the bedrock of social morality
but they are not the whole. Before we examine other forms
we shall, however, consider an objection to the way in which
we have characterized moral obligation. The fourfold criteria
which in the last section we used to distinguish it from other
forms of social standard or rule (importance, immunity from
deliberate change, the voluntary character of moral offences,
and the special form of moral pressure) are in a sense formal criteria. They make no direct reference to any necessary content
which rules or standards must have in order to be moral,
nor even to any purpose which they must serve in social life.
We have, indeed, insisted that in all moral codes there will
be found some form of prohibition of the use of violence,
to persons or things, and requirements of truthfulness, fair
dealing, and respect for promises. These things, granted only
certain very obvious truisms about human nature and the
character of the physical world, can be seen in fact to be
essential if human beings are to live continuously together in
close proximity; and it therefore would be extraordinary if
rules providing for them were not everywhere endowed with
the moral importance and status which we have described. It
seems clear that the sacrifice of personal interest which such
rules demand is the price which must be paid in a world such
as ours for living with others, and the protection they afford
is the minimum which, for beings such as ourselves, makes
living with others worth while. These simple facts constitute,
as we argue in the next chapter, a core of indisputable truth
in the doctrines of Natural Law.