Ruut Veenhoven
Conditions of Happiness, Kluwer Academic, 1984, Dordrecht/Boston.

Abstract Chapter 2

The term happiness has different meanings. In current scientific language it refers to various states of being that are considered 'good' for people as well as to different pleasurable states of mind. Here the term refers to an attitude towards one's own life. Happiness is defined as the degree to which an individual's overall evaluation of his life-as-a-whole concludes positively. As such happiness is an experience which only creatures of consciousness can undergo. It is an essentially experiential phenomenon which cannot be dentified with particular external conditions or with a way of life.
'Overall' judgements of life are presumed to draw upon more specific appraisals. Two of these seem especially relevant. The first is 'hedonic level of affect': the degree to which affective experience is dominated by pleasantness during a certain period. The second is 'contentment': the degree to which an individual perceives his conscious aims to be achieved. I refer to these appraisals as the 'affective' and the 'cognitive' component of happiness respectively. Happiness is not necessarily stable: people may change their attitudes towards life. Neither are happiness judgements always definite, nor does a persons' appreciation of life necessarily match with ethical standards.
Happiness, as defined here, must be distinguished from what is commonly referred to by terms like 'well-being', 'quality of life', 'morale', 'mental health' and 'adjustment'. However, all these terms are used in varying ways. Some of their meanings do fit the object of this study.
Finally it must be observed that the phenomenon called 'happiness' here is currently given other names as well. Terms like 'life-satisfaction', and 'psychological well-being' sometimes cover the same notion.