All passions exaggerate; it is only because they exaggerate that they are passions.

[Toutes les passions sont exagératrices, et elles ne sont des passions que parce qu’elles exagèrent.]

Nicolas Chamfort (1741-1794) French writer, epigrammist (b. Nicolas-Sébastien Roch)

Products of Perfected Civilization [Produits de la Civilisation Perfectionée], Part 1 “Maxims and Thoughts [Maximes et Pensées],” ch. 1, ¶ 72 (1795) [tr. Mathers (1926)]
    (Source)

(Source (French)). Alternate translations:

All passions are exaggerated, otherwise they would not be passions.
[tr. Hutchinson (1902)]

All of the passions lead to exaggeration. That is why they are passions.
[tr. Merwin (1969)]

All passions involve excess, in fact that's what makes them passions.
[tr. Parmée (2003), ¶59]

All passions exaggerate, and they are only passions because they exaggerate.
[tr. Sinicalchi]