Although popular culture often uses jealousy and envy as synonyms, modern philosophers and psychologists have argued for conceptual distinctions between jealousy and envy. For example, philosopher John Rawls distinguishes between jealousy and envy on the ground that jealousy involves the wish to keep what one has, and envy the wish to get what one does not have. Thus, a child is jealous of her parents' attention to a sibling, but envious of her friend's new bicycle. Psychologists Laura Guerrero and Peter Andersen have proposed the same distinction. They claim the jealous person "perceives that he or she possesses a valued relationship, but is in danger of losing it or at least of having it altered in an undesirable manner," whereas the envious person "does not possess a valued commodity, but wishes to possess it." Gerrod Parrott draws attention to the distinct thoughts and feelings that occur in jealousy and envy.