Zbigniew Herbert in the NYRB blog:
I THINK HE OFTEN repeated to himself the phrase “O Leonardo, why do you labor so?”—he who was able to look at himself from the perspective of “frozen time.”
*It appears the whole restless labor of his life was overcome by a pure and controlled art. And yet his painting is filled with disquiet.
*Leonardo’s disquiet—what do you mean? Haven’t his paintings been punctured with compasses, covered with networks of lines to prove the geometrical wisdom of his compositions, the balance of the spatial forms and the quietude of the isoceles triangles? Michelangelo is a different story, but Leonardo seems to dwell in the very self-enchanted and self-satisfied heart of the Renaissance. And yet his painting is filled with disquiet.
*Leda, the Gioconda, Benci, angels and women, goddesses and Madonnas; do you understand their smiles and the look in their widely set eyes? And the rocks, plants, and trees, the cold green waters, streams, and air—(how strangely he painted the early evening air).
So many questions, so many mysteries, or if that term irritates your reason—so many problems. And though it is a wise and self-conscious art, his painting is filled with disquiet.