For centuries, critics and observers alike have argued over if Mona Lisa is smiling. Do we now have an answer?

First, they showed participants the original "Mona Lisa" along with eight variations of the painting with the curvature of the mouth altered into happy and sad configurations. Those nine total ...

the answer to whether she is “sad” or “happy” is simple: her expression is unequivocally “happy”. Twelve participants were shown nine black and white photos of the Mona Lisa ...

The ambiguous facial expression of Mona Lisa was long thought to be one of the main reasons for its great appeal: Is she happy or sad? Scientists at the Medical Center -- University of Freiburg ...

PARIS (AP) — The “Mona Lisa” has given up another secret. Using X-rays to peer into the chemical structure of a tiny speck of the celebrated work of art, scientists have gained new insight ...

PARIS, May 30 (Reuters) - The Mona Lisa was left shaken but unharmed on Sunday when a visitor to the Louvre tried to smash the glass protecting the world's most famous painting before smearing ...