The study on Health in France has shown french people feel quite well; in fact, their welfare seems to get better even if some problems still stay, in particular about the growth of social inequalities. However, there is an important gap between these optimistic talks and the public health specialists' usual speech. Several hypothesis are expressed to explain this difference between on the one hand the real phenomenons observed with many investigation methods and on the other hand the reality felt by the observers concerned and scrupulous, the "preventologists".