The phrase ‘Esprit décadent’ is associated with decadence in the period C. 1880-c. 1890. It has been attributed to the poet Jules Laforgue and he may have ‘derived’ it from Verlaine’s sonnet Je suis l’Empire à la fin de la décadence.
It refers to the state of mind and spirit which prevailed among and was affected by a large number of poets and men of letters in France in that era. It is particularly associated with small literary societies which flourished briefly at the time, and which met for the discussion of poetry and literature in general, art, politics, philosophy, etc. Decadence (which has nothing to do with decade, from the Greek word for ten) implies decay, degeneration, a wasting away of moral (and physical) fibre and vigour. L’esprit décadent verged on a posture of affectation and was the expression of disenchantment and disillusionment with life. It associates pessimism expressive of the futility of life, a disdain of the everyday and ordinary (and natural), and a repugnance to moral and religious convention and taboo.