By a pompous parade of words, some learned men have so managed it, that an unjust cause has often gained the victory, and reason submitted to sophistry and chicane.

[Gli uomini letterati, per pompa di parlare, fanno ben spesso che il torto vince, e che la ragione perde.]

Giovanni della Casa
Giovanni della Casa (1503-1556) Florentine poet, author, diplomat, bishop
Galateo: Or, A Treatise on Politeness and Delicacy of Manners [Il Galateo overo de’ costumi], ch. 29 (1558) [tr. Graves (1774)]
    (Source)

(Source (Italian)). Alternate translations:

But, we see that Learned men have suche art and cunning to persuade, and such filed wordes to serve their turne: that wrong doth carry the cause away, and Reason cannot prevaile.
[tr. Peterson (1576)]

Men of letters, with their parade of high-flown language, very often make the wrong to prevail and the right to succumb.
[ed. Harbottle (1897)]

We find that learned men, through their grandiose talk, very often manage to have the wrong side win and reason lose.
[tr. Eisenbichler/Bartlett (1986)]