Before revision: Although these are not the only broad etiologic theories that inform homesickness, note that both theories hinge on control, the perception of which "reflects the fundamental human need for competence" (Skinner, 1995, p. 8).
After revision: Although these are not the only broad etiologic theories that inform homesickness, both theories hinge on control, the perception of which "reflects the fundamental human need for competence" (Skinner, 1995, p. 8).