The rubaiyat - omar khayyam - 11th century
It contain ~80 verses, each with wise counsel. One of my professors from school liked to quote the verse below to explian the arrow of time.
Moves on: nor all your Piety nor Wit
Shall lure it back to cancel half a Line,
Nor all your Tears wash out a Word of it.
the rubaiyat - omar khayyam - 11th century