So, I'm currently reading a book called Work and the Nature of Man, by Frederick Herzberg. This is another used book I picked up at a thrift store a few years ago, but I'm only now getting around to reading. Yes, I'm bad about not reading books right away. I've read a lot of books over my lifetime, but even so, you would not want to see my piles of unread books just gathering dust, waiting for me to pick them up.
Anyway, Frederick Herzberg was a psychologist who had this theory about workers and satisfaction in the workplace. He called it the Motivation-Hygiene theory, but it is also referred to as the Two-Factor Theory. Essentially, he says one set of factors lead to dissatisfaction in the workplace, while an entirely different set of factors lead to satisfaction in the workplace, as opposed to one set of factors that are on a continuum from satisfaction to dissatisfaction.
Read the above links for more details, but essentially, the dissatisfaction factors relate to physiological factors, or factors involving comfort and the avoidance of pain. The satisfaction factors deal with psychological factors, or factors involving accomplishments and self-actualization of the individual.
While Herzberg was focused on workplace or job satisfaction, his theory would seem to apply to general satisfaction or happiness, as well, and not just in our jobs. Herzberg himself seems to realize this, and at one point talks about what's wrong with monasticism or asceticism.
People basically have two types of needs. The first is simply taking care of material needs, to avoid pain, hunger, and other discomforts--these are physiological needs. The second set of needs involve psychological growth and development--things relating to learning, competency, goal-setting and accomplishment (or achievement). In short, factors relating to the self-actualization of the individual.
Merely meeting one's physical needs only leads to avoiding pain and discomfort, i.e., avoiding dissatisfaction, but it does not lead to satisfaction. Ascetics, realizing this, think that avoiding materialistic comforts will lead to happiness. This is flawed according to Herzberg, because it ignores the psychological needs that are necessary to real satisfaction.
So the old saying, "money can't buy happiness," seems to be true. Money can buy material comforts, ensuring that we avoid the dissatisfaction of pain and discomort, but money cannot "buy" competence, true accomplishment or achievement, or self-actualization, since that requires psychological development and growth.