“A rogue does not laugh in the same way that an honest man does;
a hypocrite does not shed the tears of a man of good faith.
All falsehood is a mask;
and however well made the mask may be,
with a little attention we may always succeed in distinguishing it
from the true face.”
Alexandre Dumas
Alexandre Dumas - The Three Musketeers
Which means: the mirror has two face.
No wearing mask on people
Masks always pose a challenge.