De parasito sive artem esse parasiticam

Lucian of Samosata

Lucian, Vol. 3. Harmon, A. M., editor. London: William Heinemann, Ltd.; Cambridge, MA: Harvard University Press, 1921.

Furthermore, if happiness lies in not hungering or thirsting or shivering, nobody has this in his power except the parasite. Consequently you can find many cold and hungry philosophers, but never a parasite; otherwise he would not be a parasite, but an unfortunate beggar fellow, resembling a philosopher.