Oh! how great a Master is the Heart!
Confess it, my beloved Singers, and gratefully own,
that you would not have arrived at the highest
Rank of the Profession if you had not been its
Scholars; own, that in a few Lessons from it, you
learned the most beautiful Expressions, the most refin'd
Taste, the most noble Action, and the most exquisite
Graces: Own, (though it be hardly credible) that the
Heart corrects the Defects of Nature, since it softens a
Voice that’s harsh, betters an indifferent one, and perfects
a good one: Own, when the Heart sings, you cannot dissemble,
nor has Truth a greater Power of persuading:
And, lastly, do you convince the World, ...that from
the Heart alone you have learned that Je ne sçai quoy,
that pleasing Charm, that so subtily passes from
Vein to Vein, and makes its way to the very Soul.

Pier Francesco Tosi Observations on the Florid Song, 1723