Jean-Michel had a sense of humour, and his passion was to play the violin. From 1948, when he joined the French Communist Party (PCF), he conducted revolutionary choirs and continued to do so unceasingly, including during the summer universities of the Revolutionary Communist League (LCR). Sometimes he lost some of his humour when singers suggested modernizing the repertoire; he remained very much attached to the traditions of the labour movement. He had courage, as evidenced by the periods he spent in the maquis in Vietnam and Thailand. He participated in major events such as the Russell Tribunal against war crimes in Vietnam. He did not grudge taking on the most obscure militant tasks: right to the end, he devoted his attention to correcting the articles published in the magazine Inprecor.