Human beings consider themselves satisfied only compared to some other condition. A man who has owned nothing but a bicycle all of his life feels suddenly wealthy the moment he buys an automobile...But this happy sensation wears off. After a while the car becomes just another thing that he owns. Moreover, when his neighbor next door buys two cars, in an instant our man feels wretchedly poor and deprived.
Alan Lightman, Reunion
attitude, gratitude, privilege