violate an engagement, either express or implied, or disappoint
expectations raised by our own conduct, at least if we have raised those
expectations knowingly and voluntarily. Like the other obligations of
justice already spoken of, this one is not regarded as absolute, but as
capable of being overruled by a stronger obligation of justice on the
other side; or by such conduct on the part of the person concerned as is
deemed to absolve us from our obligation to him, and to constitute a
_forfeiture_ of the benefit which he has been led to expect.

Fifthly, it is, by universal admission, inconsistent with justice to be
_partial_; to show favour or preference to one person over another, in
matters to which favour and preference do not properly apply.
Impartiality, however, does not seem to be regarded as a duty in itself,
but rather as instrumental to some other duty; for it is admitted that
favour and preference are not always censurable, and indeed the cases in
which they are condemned are rather the exception than the rule. A
person would be more likely to be blamed than applauded for giving his
family or friends no superiority in good offices over strangers, when he
could do so without violating any other duty; and no one thinks it
unjust to seek one person in preference to another as a friend,
connexion, or companion. Impartiality where rights are concerned is of
course obligatory, but this is involved in the more general obligation
of giving to every one his right. A tribunal, for example, must be
impartial, because it is bound to award, without regard to any other
consideration, a disputed object to the one of two parties who has the
right to it. There are other cases in which impartiality means, being
solely influenced by desert; as with those who, in the capacity of
judges, preceptors, or parents, administer reward and punishment as
such. There are cases, again, in which it means, being solely influenced
by consideration for the public interest; as in making a selection among