On Anger, Book 1, Section 3 — In Plain English

Seneca — The Senator

Only humans have been given wisdom, foresight, hard work, and deep thought. Animals are forbidden not just human virtues, but even human vices. Their whole makeup — mind and body — is completely different from ours. Their ruling principle comes from a different source entirely. Take their voice, for example. They have one, but it's unclear and can't form real words. They have a tongue, but it's clumsy and can't handle complex movements. They also have intellect — the greatest gift of all — but theirs is rough and imprecise. It can only grasp dim images and shadows that push them to act, and even then only in a cloudy, unclear way. This is why their impulses and outbursts are so violent. They don't actually feel fear, worry, grief, or anger — just rough copies of these feelings. That's why they drop them so quickly and switch to the opposite. After showing the most intense rage and terror, they go back to grazing peacefully. After wild bellowing and thrashing, they immediately fall into calm sleep.

Seneca — The Senator Original

To no creature besides man has been given wisdom, foresight, industry, and reflexion. To animals not only human virtues but even human vices are forbidden: their whole constitution, mental and bodily, is unlike that of human beings: in them the royal and leading principle is drawn from another source, as, for instance, they possess a voice, yet not a clear one, but indistinct and incapable of forming words: a tongue, but one which is fettered and not sufficiently nimble for complex movements: so, too, they possess intellect, the greatest attribute of all, but in a rough and inexact condition. It is, consequently, able to grasp those visions and semblances which rouse it to action, but only in a cloudy and indistinct fashion. It follows from this that their impulses and outbreaks are violent, and that they do not feel fear, anxieties, grief, or anger, but some semblances of these feelings: wherefore they quickly drop them and adopt the converse of them: they graze after showing the most vehement rage and terror, and after frantic bellowing and plunging they straightway sink into quiet sleep.

Seneca — The Senator

We have to admit that no animal except humans can feel anger. Wild beasts and other creatures can't be angry because anger is the enemy of reason, and it can only exist where reason lives. Wild beasts have impulses, fury, cruelty, and a fighting spirit. But they don't have anger any more than they have luxury. Yet they do give in to certain pleasures with even less self-control than we do. Don't believe the poet who says: "The boar forgets his wrath, the stag forgets the hounds. The bear forgets how he leaped frantically among the herd." When he talks about angry beasts, he just means they're excited and stirred up. They know no more about being angry than they know about forgiving. Animals don't have human emotions, but they do have certain impulses that look similar to ours. If they could really feel love and hate, they would also be able to form friendships and enemies, to disagree and agree. You can see hints of these qualities in them, but properly speaking, all emotions — both good and bad — belong only to human hearts.

Seneca — The Senator Original

We must admit, however, that neither wild beasts nor any other creature except man is subject to anger: for, whilst anger is the foe of reason, it nevertheless does not arise in any place where reason cannot dwell. Wild beasts have impulses, fury, cruelty, combativeness: they have not anger any more than they have luxury: yet they indulge in some pleasures with less self-control than human beings. Do not believe the poet who says: "The boar his wrath forgets, the stag forgets the hounds. The bear forgets how 'midst the herd he leaped with frantic bounds." When he speaks of beasts being angry he means that they are excited, roused up: for indeed they know no more how to be angry than they know how to pardon. Dumb creatures have not human feelings, but have certain impulses which resemble them: for if it were not so, if they could feel love and hate, they would likewise be capable of friendship and enmity, of disagreement and agreement. Some traces of these qualities exist even in them, though properly all of them, whether good or bad, belong to the human breast alone.