[3] His uncle, the banker Henri Bamberger, was co-founder of the Banque de Paris et des Pays-Bas.

[1] Lévy joined his uncle's Banque de Paris et des Pays-Bas, where he was responsible for a number of foreign inquiries in which he showed his business acumen.

He was interested in turn in South African gold mines, the Crédit Mobilier, the Franco-Chinese economic association and the Channel Tunnel.

[4] With the outbreak of World War I (1914-18) Lévy remained in Paris and converted his town house into a military hospital, keeping two modest rooms for himself and his wife.

On 9 February 1917 Le Figaro reported that by a large majority Levy had been elected president of the Societe d'Économie politique.

He supported liberal economic policies, and was opposed to laws preventing export of capital, against excessive taxes on securities which would threaten savings, and against obstacles to the wheat trade.

[1] Lévy published many books on economics, but his first publication was a volume of poems inspired by Alfred de Musset.

[7] In Banques d'émission et trésors publics (1911) Levy made the case that exchange rate stability depended on the central bank being independent of the state.

He wrote that "the less public authority gets involved with the management of the banking system, the better national credit and wealth are protected.