The Complete Aristotle (eng.)

is concerned, the man with
a turn for oratory looks for respect from one who cannot speak; the
ruler demands the respect of the ruled, and the man who thinks he
ought to be a ruler demands the respect of the man whom he thinks
he ought to be ruling. Hence it has been said
Great is the wrath of kings, whose father is Zeus almighty,
    and
Yea, but his rancour abideth long afterward also,
    their great resentment being due to their great superiority.
Then again a man looks for respect from those who he thinks owe him
good treatment, and these are the people whom he has treated or is
treating well, or means or has meant to treat well, either himself,
or through his friends, or through others at his request.
    It will be plain by now, from what has been said, (1) in what
frame of mind, (2) with what persons, and (3) on what grounds
people grow angry. (1) The frame of mind is that of one in which
any pain is being felt. In that condition, a man is always aiming
at something. Whether, then, another man opposes him either
directly in any way, as by preventing him from drinking when he is
thirsty, or indirectly, the act appears to him just the same;
whether some one works against him, or fails to work with him, or
otherwise vexes him while he is in this mood, he is equally angry
in all these cases. Hence people who are afflicted by sickness or
poverty or love or thirst or any other unsatisfied desires are
prone to anger and easily roused: especially against those who
slight their present distress. Thus a sick man is angered by
disregard of his illness, a poor man by disregard of his poverty, a
man aging war by disregard of the war he is waging, a lover by
disregard of his love, and so throughout, any other sort of slight
being enough if special slights are wanting. Each man is
predisposed, by the emotion now controlling him, to his own
particular anger. Further, we are angered if we happen to be
expecting a contrary result: for a quite unexpected evil is
specially painful, just as the quite unexpected fulfilment of our
wishes is specially pleasant. Hence it is plain what seasons,
times, conditions, and periods of life tend to stir men easily to
anger, and where and when this will happen; and it is plain that
the more we are under these conditions the more easily we are
stirred.
    These, then, are the frames of mind in which men are easily
stirred to anger. The persons with whom we get angry are those who
laugh, mock, or jeer at us, for such conduct is insolent. Also
those who inflict injuries upon us that are marks of insolence.
These injuries must be such as are neither retaliatory nor
profitable to the doers: for only then will they be felt to be due
to insolence. Also those who speak ill of us, and show contempt for
us, in connexion with the things we ourselves most care about: thus
those who are eager to win fame as philosophers get angry with
those who show contempt for their philosophy; those who pride
themselves upon their appearance get angry with those who show
contempt for their appearance and so on in other cases. We feel
particularly angry on this account if we suspect that we are in
fact, or that people think we are, lacking completely or to any
effective extent in the qualities in question. For when we are
convinced that we excel in the qualities for which we are jeered
at, we can ignore the jeering. Again, we are angrier with our
friends than with other people, since we feel that our friends
ought to treat us well and not badly. We are angry with those who
have usually treated us with honour or regard, if a change comes
and they behave to us otherwise: for we think that they feel
contempt for us, or they would still be behaving as they did
before. And with those who do not return our kindnesses or fail to
return them adequately, and with those who oppose us though they
are our inferiors: for all such persons seem to feel contempt for
us; those who oppose us seem to think us inferior to themselves,
and those who do not return our kindnesses seem to think that those
kindnesses were conferred by inferiors. And we feel particularly
angry with men of no account at all, if they slight us. For, by our
hypothesis, the anger caused by the slight is felt towards people
who are not justified in slighting us, and our inferiors are not
thus justified. Again, we feel angry with friends if they do not
speak well of us or treat us well; and still more, if they do the
contrary; or if they do not perceive our needs, which is