The difference between passion and seriousness is that the passionate man focuses on a project while the serious man focuses on a value system (although, of course, the serious man also adopts projects prescribed by that value system). If the adventurer exercises his freedom so zealously that he forgets to focus on morally meaningful projects, the passionate man is so fixated on a specific meaningful project that he loses his freedom because he forgets that he could choose to pursue other meaningful projects as well. For de Beauvoir, people choose goals for the sake of the joy they feel in free action, whereas intuitively people tend to think that they only undertake action for the sake of goals they are attached to achieving. Disclosing the joy of existence means revealing the energy one puts into one’s free action in the pursuit of those ends-but without attachment to the ends themselves. To give oneself a new “human signification” is to develop a mental image of what one wants to be and devote oneself to projects that lead one toward that image of the self. To trace this process of growth, she turns back to Sartre’s picture of a human as “a being who makes himself a lack of being in order that there might be being.” Making oneself “a lack of being” means recognizing the arbitrariness of adult values, and therefore one’s own lack of a definite, singular identity ( being).

De Beauvoir shows that the move from natural to moral freedom can also be understood as the evolution from childhood to maturity.

De beauvoir the ethics of ambiguity