Eyor Dedonki was the writer of Memoirs of a Pessimist in 479.M41. Commissar Ciaphas Cain sometimes quoted Dedonki's writings to his students at the Schola Progenium.
- "If you don't expect gratitude, you'll seldom be disappointed."
The name bears a strong resemblance to Eeyore, from the Winnie the Pooh books, in character. Both are pessimists and both seem not to expect hope for fear of losing it.