His maternal uncle, José Antonio de Rojas motivated him by granting him access to his library, at that point the most extensive in Chile.

In Chile, the Royal Governor Francisco Antonio García Carrasco had been forced to resign due to his ineptitude and corruption, and had been replaced by Mateo de Toro y Zambrano.

So, after Mateo de Toro y Zambrano took over as Royal Governor, he was convinced to call an open meeting of the leading citizens of the city to decide the political future of the colony.

In the first meeting he asked for the convocation of a popular congress to declare the independence of the nation, and, notwithstanding strong opposition, carried his point.

In 1814 he was sent as diplomatic agent to the revolutionary government of Buenos Ayres, where he remained for some time, but due to the after-effects of the disaster of Rancagua, he was forced to seek refuge in the United Provinces of the Rio de la Plata.

When General Freire marched for the second time against the Spanish forces in the archipelago of Chiloe in 1824, he instituted a council of regency, of which Infante became president.

The Constitution of 1823 (promulgated after the resignation of O'Higgins) had a very short life, and was abrogated in 1826 in order to discuss the system of government that was to rule the country.

Infante was an admirer of the United States, and in 1826, as senator laid before congress a proposition to form a federal republic.

As his ideas were not generally accepted, he supported them by founding in 1827 the newspaper "El Valdiviano Federal" of which he was the editor, and till his death he continued to write all the leading articles for this paper.

The principal reason behind the collapse of the attempt was that it run counter to the long tradition of centralized government in the country.

Nonetheless, his constant opposition to the government caused him to be expelled from the chamber with the argument that the election had not been held properly.