The scientific study of optimal human functioning is positive psychology, and one of its most important subjects is happiness. Positive psychology is a late fruit of the European ‗Enlightenment‘, the intellectual tradition that contested the religious view on happiness that dominated in the Middle Ages. Whereas religion told that happiness could be found only in the afterlife and that life on Earth was not meant to be enjoyable, the Enlightened thinkers deemed happiness both possible and desirable. One of the most influential proponents of that view was Jeremy Bentham. In his 1789 book on ’Morals and Legislation‘ he made happiness the basis of a moral philosophy, which the moral value of any action depends on its contribution to human happiness, the best action being the one that results in the ’greatest happiness for the greatest number‘. Application of this principle to individual choice is called ’actor utilitarianism‘ and application of it to policy making is called ’political utilitarianism‘ or ’rule utilitarianism‘.
This thesis is inspired by his ideology, and tries to add to the utilitarian tradition in three ways. The first part of this thesis considers to what extend advice can create greater happiness, What is the quality of the advice that has been given through the centuries and how well does it fit whit what we now know about the conditions of happiness? Is the psychologist Daniel Gilbert right in his statement that ’Everyone has an opinion about happiness and unfortunately many of them write books‘? The second part is about how mental disorders affect the happiness of the great numbers of people that suffer from mental disorders. This is a neglected area of research, probably because the answer seems obvious. After all, suffering for the self or pain inflicted on others is the principal component of mental disorders. Is it true that mental disorders exclude happiness, and what are the clinical characteristics that are
associated with lower happiness in the context of mental disorders?
The third part of the thesis deals with the limits of utilitarianism. How are wisdom and happiness related, and is there a limit to maximizing pleasure and preventing pain
in individual lives?