His philosophy teacher was Adelchi Baratono, a reformist socialist who contributed to his approach to socialism and probably introduced him to the inner circles of the Ligurian labour movements.

After the armistice in 1918, he joined the Unitary Socialist Party, PSU, then he settled in Florence where he also graduated in political science with a thesis entitled La Cooperazione ("Cooperation"; 1924).

According to the Italian historian of Freemasonry Aldo Alessandro Mola, during that period Pertini had relationships with exponents of the Grand Orient of Italy who were in exile in France.

Pertini then travelled north to organize partisan war as an executive member of PSI (alongside Rodolfo Morandi and Lelio Basso).

[7] Despite his advanced age, he displayed considerable energy and vigour, playing a major role in helping restore the public's faith in the government and institutions of Italy, as well as maintaining an active schedule of travelling and meeting foreign dignitaries.

He also opposed organized crime in Italy, South African apartheid, Chilean dictator Augusto Pinochet and other dictatorial regimes, as well as the Soviet invasion of Afghanistan.

The only official role he accepted in his retirement was President of the "Filippo Turati" Foundation for Historical Studies of Florence inaugurated in 1985 and dedicated to recording and preserving the history of the socialist movement in Italy.

[8] Memorable images from the event are Pertini standing on his chair at Santiago Bernabeu stadium, exulting in the Italian victory, and the card game on the return flight, between the president and three team members (trainer Bearzot and players Causio and Zoff), the world cup trophy next to them on the table.

Paolo Rossi, Italy's and the tournament's top scorer, later said: "I remember that when he welcomed us at the Presidential Palace after our win, he rose and said: 'This is my best day as President.

'"[9] Sandro Pertini had a close friendship with Pope John Paul II, with whom he met often both for official and private occasions, and had frequent phone conversations.