  A central feature of desire-based theories of well-being is that they take actual states of affairs to be what is important to a person's well-being, rather than the person's perceptions of actuality. Thus, if I desire that I win an Olympic gold medal, then I am only well off in this respect if I win the medal: if I get tricked into believing that I have won the medal when I have not, then my well-being has not been increased in the relevant respect. This might be an advantage for desire-based theories of well-being (mere trickery seems unlikely to increase my actual well-being) or it might be a disadvantage (what I do not know cannot hurt me, can it?). Discussion of this point is ongoing (e.g., Sumner 1996).