Observed effects of happiness
The possible effects of happiness considered in the above chapters can be grouped into six categories: 'outlook', 'health', 'marriage', 'work', 'vigilance' and 'events'. In all of these categories we came across indications of causal effects of happiness. In two cases can that evidence be considered convincing.
The appreciation of life-as-a-whole affects the evaluation of various aspects of life.Chapter 10 provided sound evidence of effects on satisfaction with marriage, job and the standard of living. However, not all domain satisfactions appear to be influenced by happiness: satisfaction with health and with social support were not. Chapter 10 also showed that happiness produces a more positive assessment of the fit between one's situation and expectations, aspirations and entitlements. Chapter 8 demonstrated a similar effect of happiness on the assessment of the consequences of unemployment. Chapter 10 also showed that happiness fosters a sense of relative superiority, which means that it strengthens subjective self-reliance.
The degree of these effects can only be roughly estimated. The rigorous controls of chapter 10 mark a minimum explained variance of 4% in the case of separate satisfactions and 15% in the case of self-perceived competence. Zero-order correlations mark a maximum of about 30%
Three chapters considered the effects of happiness on health. Chapter 6 showed fairly convincingly that happy people live somewhat longer. Happiness at age 60 explains 1 to 8 % of the variance in longevity. The longer life of the happy is probably not the result of a lower vulnerability to stress. Chapter 2 fairly convincingly rejected the hypothesis that happiness buffers stress. Is the longer life of the happy a result of better recovery chances in case of illness? Chapter 3 suggests it is not. Yet the data presented in that chapter cannot decide the issue, because they specifically concern cancer and do not quite fit the concept of happiness being used here. Hence this possibility remains open for the time being.
Chapter 6 presented several indications of an effect of happiness on marriage chances. The happy seem to have a better chance of finding a spouse and seem to be less prone to divorce. Yet the evidence was not quite conclusive. The size of this effect is maximally some 5% of the variance in marital status.
There are indications that happiness fosters employment chances and work productivity, but again evidence is not conclusive (chapter 6 resp. chapter 9). If relevant at all, the size of the effects tends to be quite small. Possibly the effects of happiness on work performance is more sizable at the higher occupational levels.
The chapters 4 and 7 suggest that happiness does not make people docile and may even foster active action both in private matters and in public issues. Yet the evidence presented in these chapters is not conclusive: the study designs do not allow the identification of independent causal effects and the data do not concern happiness in the strict sense of the word.
Life eventsThere are indications that happiness affects good luck. Chapter 10 showed that a positive appreciation of life predicts the report of relatively many favorable life events. It is as yet unclear to what degree this effect is a mere perceptual phenomenon.
Proposed causal mechanisms
In the foregoing chapters we met with several suggestions about possible causal mechanisms behind the presumed effects of happiness. The claims concern perceptual matters in the first place and further 'activation', 'social contacts' and 'personality development'. Only in the first case is there convincing empirical evidence.
Several contributions mentioned 'outlook' as a possible causal mechanism. Chapter 2 set out with the suggestion that happiness buffers stress by fostering a more positive outlook on the problems of life and on one's ability to cope with them. Likewise chapter 3 proposed that happiness may help to overcome disease, because its perceptual effects prevent people giving up prematurely. In the same vein chapter 4 suggests that the slightly greater self-care of satisfied patients comes about through a more positive outlook on themselves and on their control of the situation. These latter mechanisms are also mentioned in chapter 6 as links in the relationship between happiness and marriage chances.
As we have seen in chapter 10 there is good evidence that happiness does induce a more positive outlook. However, it is not yet established that this effect on outlook materializes in less stress, better recovery, moreself-care or better marriage chances.
In two of the contributions effects of happiness by way of 'better health' were suggested. Chapter 2 mentions the possibility that the happy can take more knocks because they tend to be healthier. Chapter 8 mentions health effects of happiness as a possible reason for the slightly better employment chances of the happy. As we have seen there is some evidence that happiness does indeed tend to foster health: we can at least be reasonably sure that happiness lengthens life. However, there is not yet proof for the proposed intermediary effects.
Several contributions suggest effects through greater 'alertness' and 'activity'. All refer to earlier research showing the energizing effects of pleasant affect. In this context chapter 2 proposes that the happy cope with stress better because they cope more actively. Chapter 4 mentions greater energy as the reason why satisfied patients take better care of themselves. Chapter 6 refers to this matter in the context of marriage chances and chapter 8 in the context of employment-chances. Chapter 10 also hints at this effect in the discussion on the possibility that the happy are more satisfied with various aspects of life because they have in fact created better living conditions for themselves. None of the contributions could demonstrate these explanations empirically.
Facilitation of social contacts was also mentioned as a mediator variable. Chapter 6 presented evidence that happiness facilitates social contacts, among other things because cheerful people are better liked. Chapter 2 suggests that this facilitates the mobilization of social support, which in its turn facilitates coping with stress. Chapter 8 mentions social contacts as a possible reason for better employment chances: finding a new job is facilitated through smoother social contacts because it gives better access to the informal job market; the chances of keeping one's job may be strengthened through better contacts with colleagues. Chapter 10 also hints to this effect in the discussion on the possibility that happy people create themselves better living conditions.
Though it is quite plausible that happiness facilitates social contacts, this effect has not been demonstrated conclusively as yet. There is no empirical evidence at all for the claimed ntermediate effects. Thus, for the time being, this remains pure hypothesis.
Finally there is the claim that happiness affects personality development and thus involves long term consequences in many spheres of life. This possibility is mentioned in chapter 6 in the discussion of the reasons for the better marriage chances of the happy. It is suggested that a positive appreciation of life facilitates the development of traits like 'empathy', 'self-esteem' and 'inner-control' which are crucial requirements in the modern relationship pattern. The same argument can also be applied to observed differences in 'self-care', 'political vigilance' and 'work performance' .
Yet it is not at all sure that happiness seriously affects personality development. Though there is good evidence for strong correlations over time it is still largely unclear what is cause and what effect. Therefore this explanation remains hypothetical as well.
Indications of harm and benefit
The introductory chapter to this book set out with an enumeration of claimed harmful effects of happiness (page 2) . Subsequently several claims to the contrary were presented: claimed benefits of happiness (page 2-3. Let us now take stock of the evidence provided by the later chapters:
No harm demonstrated
Three possible harmful effects of enjoying life were mentioned: contentment'. a 'too rosy view' and 'social isolation.'
Several indications of beneficial effects
Six possible positive consequences of enjoying life were mentioned: More 'intimacy', greater 'activity'. sharper 'awareness', less 'vulnerability to stress', protection of 'health' and better psychological development'.
There are no indications that the claimed negative effects of happiness exist, but there are good indications for several of the claimed positive effects. All in all: happiness does not appear to be that detrimental.