Environmental Engineering Reference
In-Depth Information
Fig. 3.9
Annual change in
GDP per capita and mean
personal happiness in the
USA. (From Frey and Stutzer
2001
)
Fig. 3.10
Changes in satisfaction level and GDP per capita in Japan. (1958-1991)
To gain some insight into this conundrum, we can refer to the work of Ameri-
can psychologist, Abraham Maslow, who investigated human needs, and derived
his theory of needs hierarchy (Maslow
1943
). Based on his theory, there are five
levels of human needs: the basic level is the physiological need- what is needed to
maintain life (food, water, sleep, procreation); the second can be seen as related to
