The issue of smiling and face masks is discussed in this recent piece in the Jewish Journal that reminds us of Shammai's injunction (Avot 1:15) to greet everyone with a happy, smiling face. This applies just as much to people who wear a face-mask, just as it should do to people one encounters in the dark. This is not just because a smile makes a favourable impact on the person greeted -- it also affects the mood of the person doing the greeting (the 'smilor' rather than the 'smilee'). So do remember to smile and greet others warmly: it's good for your health too!
Thoughts on Pirkei Avot -- the Ethics of the Fathers -- and on their meaning and their relevance to contemporary living