[13] A founding member of the Spanish Abolitionist Society back in 1864,[14] he took measures during his first ministerial tenure towards the abolition of slavery in Puerto Rico, presenting two proposals in 1869, which were not welcomed either by his cabinet peers or from the parliament.

[15] After months of fierce resistance to the ministerial initiatives from pro-slavery legislators such as Antonio Cánovas del Castillo or Francisco Romero Robledo, Becerra was forced to resign in March 1870 amid intense pressure.

[16] Already entered the reign of Amadeo, during the premiership of Manuel Ruiz Zorrilla, Becerra was appointed as Minister of Development in December 1872, replacing José Echegaray.

[17] Following the Bourbon Restoration, Becerra joined the Liberal Fusionist Party led by Práxedes Mateo Sagasta as part of its left-leaning faction.

[21] Elected to the Royal Academy of Sciences in 1885, he took office as numerary member (Medal #36) on 18 November 1886,[22] reading a discourse titled Evolución de la Matemática e influencia que en los progresos de esta ciencia ejerció la civilización árabe ("Evolution of Mathematics and the influence of the Arab civilization on the progress of this science"), replied by Eduardo Saavedra.