Authors:

Know thyself' was written over the portal of the antique world. Over the portal of the new world, 'Be thyself' shall be written.

Oscar Wilde, Russell Jackson, Ian Small (2000). “The Complete Works of Oscar Wilde: De profundis, "Epistola : in carcere et vinculis"”, p.305, Oxford University Press on Demand
Know thyself' was written over the portal of the antique world. Over the portal of the new world, 'Be thyself' shall be written.