“In love, women are professionals, men are amateurs”
François Truffaut
Truffaut and Marie Dubois on the set of Tirez sur le pianiste (Shoot the Piano Player), 1960
The etymology and historical meaning of the term professional is, “from Middle English, from profes, adjective, having professed one’s vows, from Anglo-French, from Late Latin professus, from Latin, past participle of profitēri to profess, confess, from pro- before + fatēri to acknowledge; in other senses, from Latin professus, past participle”.
An amateur (French amateur “lover of”, from Old French and ultimately from Latin amatorem nom. amator, “lover”) is generally considered a person attached to a particular pursuit, study, or science in a non-professional or unpaid manner. Amateurs often have little or no formal training in their pursuits, and many are autodidacts (self-taught).