For Epicurus, there are some fears that are perfectly legitimate; so too are some desires. Epicurus offers a classification of desires into three types: some are natural, others are empty; and natural desires are of two sorts, those that are necessary and those that are merely natural (see Cooper 1999). Natural and necessary are those that look to happiness, physical well-being, or life itself (LM 127). Unnecessary but natural desires are for pleasant things like sweet odors and good-tasting food and drink (and for various pleasurable activities of sorts other than simple smelling, touching and tasting). Empty desires are those that have as their objects things designated by empty sounds, such as immortality, which cannot exist for human beings and do not correspond to any genuine need. The same holds for the desire for great wealth or for marks of fame, such as statues: they cannot provide the security that is the genuine object of the desire. Such desires, accordingly, can never be satisfied, any more than the corresponding fears — e.g., the fear of death — can ever be alleviated, since neither has a genuine referent, i.e., death as something harmful (when it is present, we do not exist) or wealth and power as salves for anxiety. Such empty fears and desires, based on what Epicurus calls kenodoxia or empty belief, are themselves the main source of perturbation and pain in civilized life, where more elementary dangers have been brought under control, since they are the reason why people are driven to strive for limitless wealth and power, subjecting themselves to the very dangers they imagine they are avoiding. SEP Entry on Epicurus