The face of a woman in ecstasy (left); a female face expressing simple love (right). Etching by B. Picart, 1713, after C. Le Brun.

Le Brun's depiction of the passions illustrates his theory of the passions, delineated in the 'Conférence'. In Cartesian style, each compound passion is an organisation of the six simple passions of admiration, love, hatred, desire, joy and sadness. For instance, jealousy is a composite of love and hate; despair "is a strong persuasion of not being able to obtain what we desire"