The Collaborative International Dictionary of English v.0.48:

Eudemonism \Eu*de"mon*ism\, Eudaemonism \Eu*d[ae]"mon*ism\, n.
   [Gr. ? a thinking happy, fr, ? blessed with a good genius,
   happy; e'y^ 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. Eudemonist

WordNet (r) 3.0 (2006):

eudemonism
    n 1: an ethical system that evaluates actions by reference to
         personal well-being through a life based on reason [syn:
         eudemonism, endaemonism]