The connection between the justice and injustice of the
compensation for injury, and the principle 'Treat like cases
alike and different cases differently', lies in the fact that outside
the law there is a moral conviction that those with whom
the law is concerned have a right to mutual forbearance from
certain kinds of harmful conduct. Such a structure of reciprocal
rights and obligations proscribing at least the grosser sorts of harm, constitutes the basis, though not the whole, of
the morality of every social group. Its effect is to create among
individuals a moral and, in a sense, an artificial equality to
offset the inequalities of nature. For when the moral code
forbids one man to rob or use violence on another even when
superior strength or cunning would enable him to do so with
impunity, the strong and cunning are put on a level with the
weak and simple. Their cases are made morally alike. Hence
the strong man who disregards morality and takes advantage
of his strength to injure another is conceived as upsetting this
equilibrium, or order of equality, established by morals; justice
then requires that this moral status quo should as far as
possible be restored by the wrongdoer. In simple cases of
theft this would simply involve giving back the thing taken;
and compensation for other injuries is an extension of this
primitive notion. One who has physically injured another
either intentionally or through negligence is thought of as
having taken something from his victim; and though he has
not literally done this, the figure is not too far-fetched: for he
has profited at his victim's expense, even if it is only by indulging
his wish to injure him or not sacrificing his ease to
the duty of taking adequate precautions. Thus when laws
provide compensation where justice demands it, they recognize
indirectly the principle 'Treat like cases alike' by providing
for the restoration, after disturbance, of the moral status
quo in which victim and wrongdoer are on a footing of equality
and so alike. Again, it is conceivable that there might be
a moral outlook which did not put individuals on a footing of
reciprocal equality in these matters. The moral code might
forbid Barbarians to assault Greeks but allow Greeks to assault
Barbarians. In such cases a Barbarian may be thought
morally bound to compensate a Greek for injuries done though
entitled to no such compensation himself. The moral order
here would be one of inequality in which victim and wrongdoer
were treated differently. For such an outlook, repellent
though it may be to us, the law would be just only if it reflected
this difference and treated different cases differently.