I love to see two truths at the same time. Every good comparison gives the mind this advantage.

[J’aime à voir deux vérités à la fois. Toute bonne comparaison donne à l’esprit cet avantage.]

Joseph Joubert (1754-1824) French moralist, philosopher, essayist, poet
Pensées [Thoughts], Introduction, “L’auteur Peint par Lui-Même [The Author’ Self-Portrait]” (1850 ed.) [tr. Auster (1983)], 1796]
    (Source)

(Source (French)). Alternate translations:

I like to see two truths at once. Every good comparison gives the mind this advantage.
[tr. Calvert (1866), "Notice"]

I like to see two truths at once. Every good comparison gives the mind that advantage.
[tr. Collins (1928)]