Sorrow is the worst thing in life ... is the first line, and name, of a poem written in Irish, as an elegy for Féilim Mac Maghnusa Méig Uidhir, who died in 1487. He was a brother of Cathal Óg Mac Maghnusa. The author of the poem is unknown. It is found on folio 15 verso of , which consists for the most part of the Annals of Ulster, compiled by Féilim's brother, Cathal Óg. It consists of thirty-two quatrains written in two columns in the strict form of rannaigheacht mhór.