Lying.

 La verdad Sospechosa is the best example of Alarcón's contribution to Spanish, Golden Age drama.
I studied this text at university and it is all about a young, well-born man who tells lies. His father is informed of this in a most roundabout and careful way with the words 'No siempre dice la verdad.' - 'He doesn't always tell the truth.' Note the gentle way this ignoble vice is presented to a shocked and horrified parent.

Reports over the last few days suggest that lying in our nation is now endemic. What a downward spiral we are in.