On Anger, Book II, III

None of these things which casually influence the mind deserve to be called passions: the mind, if I may so express it, rather suffers passions to act upon itself than forms them.

A passion, therefore, consists not in being affected by the sights which are presented to us, but in giving way to our feelings and following up these chance promptings: for whoever imagines that paleness, bursting into tears, lustful feelings, deep sighs, sudden flashes of the eyes, and so forth, are signs of passion and betray the state of the mind, is mistaken, and does not understand that these are merely impulses of the body.

Consequently, the bravest of men often turns pale while he is putting on his armour; when the signal for battle is given, the knees of the boldest soldier shake for a moment; the heart even of a great general leaps into his mouth just before the lines clash together, and the hands and feet even of the most eloquent orator grow stiff and cold while he is preparing to begin his speech.

Anger must not merely move, but break out of bounds, being an impulse: now, no impulse can take place without the consent of the mind: for it cannot be that we should deal with revenge and punishment without the mind being cognisant of them.

A man may think himself injured, may wish to avenge his wrongs, and then may be persuaded by some reason or other to give up his intention and calm down: I do not call that anger, it is an emotion of the mind which is under the control of reason.

Anger is that which goes beyond reason and carries her away with it: wherefore the first confusion of a man’s mind when struck by what seems an injury is no more anger than the apparent injury itself: it is the subsequent mad rush, which not only receives the impression of the apparent injury, but acts upon it as true, that is anger, being an exciting of the mind to revenge, which proceeds from choice and deliberate resolve.

There never has been any doubt that fear produces flight, and anger a rush forward; consider, therefore, whether you suppose that anything can be either sought or avoided without the participation of the mind.