The Vegetable Gardener (1587–1593) by Giuseppe Arcimboldo (1526 - 1593) Turn it upside down, and all will be revealed.
Scholars Consulting Books and a Globe (1747) by Giovanni Francesco Costa (1711 - 1772) Use a mirror, and be amazed!
Reflections, or the Music Lesson (date unknown) by Thomas Rowlandson (1757 - 1827) Yep. Mirrors are useful.
The Experts (1837) by Alexandre-Gabriel Decamps (1803 - 1860) Everyone's a critic.
L.H.O.O.Q, Mona Lisa with moustache (1919) by Marcel Duchamp (1887 - 1968) Anything you can do, I can do better.
Clairvoyance (1936) Self-portrait by Rene Magritte (1898 - 1967) This guy is good!
Note* All works are in the public domain or available for fair use.
