P44: Love and Desire can be excessive.

Dem.: Love is Joy, accompanied by the idea of an external cause (by Def. Aff. VI). Pleasure, therefore (by IIIP11 S), accompanied by the idea of an external cause, is Love.

And so, Love (by P43) can be excessive.

Again, Desire is greater as the affect from which it arises is greater (by IIIP37).

Hence, as an affect (by P6) can surpass the rest of man’s actions, so also the Desire which arises from that affect can surpass the rest of his Desires. It can therefore be excessive in the same way we have shown Pleasure can be (in P43), q.e.d.

Schol.: Cheerfulness, which I have said is good, is more easily conceived than observed.

For the affects by which we are daily torn are generally related to a part of the Body which is affected more than the others. Generally, then, the affects are excessive, and occupy the Mind in the consideration of only one object so much that it cannot think of others. And though men are liable to a great many affects, so that one rarely finds them to be always agitated by one and the same affect, still there are those in whom one affect is stubbornly fixed. For we sometimes see that men are so affected by one object that, although it is not present, they still believe they have it with them.

When this happens to a man who is not asleep, we say that he is mad or insane. Nor are they thought to be less mad who burn with Love, and dream, both night and day, only of a lover or a courtesan. For they usually provoke laughter. But when a greedy man thinks of nothing else but profit, or money, and an ambitious man of esteem, they are not thought to be mad, because they are usually troublesome and are considered worthy of Hate. But Greed, Ambition, and Lust really are species of madness, even though they are not numbered among the diseases.