Source : Webster's Revised Unabridged Dictionary (1913)

Eudemonism \Eu*de"mon*ism\, Eudaemonism \Eu*d[ae]"mon*ism\, n.
   [Gr. ? a thinking happy, fr, ? blessed with a good genius,
   happy; ? well, good + ? one's demon of genius. See {Demon}.]
   That system of ethics which defines and enforces moral
   obligation by its relation to happiness or personal
   well-being.