Dominated by the need to live, these nations created a political philosophy. They disregarded criticism and analysis; they affirmed and constructed; they required a faith as intolerant as the archaic dogmas. Democracy and liberalism were the essential articles of this secular religion. To the eyes of the new orthodoxy the convictions of the monarchists and absolutists were dangerous heresies: royalists were prosecuted as free-thinkers had been of old. Thought was not divorced from action. It reflected the political unrest; it prepared or justified political transformations. A species of pragmatism was characteristic of American thought. Poetry was rhymed oratory, lyrical declamation; the poet condemned any form of civil autocracy; he execrated tyrants, or evoked ingenuous liberties; he could not conceive of pure thought as divorced from life. Alberdi, an Argentine thinker, wrote: "Philosophy is meant for politics, morality, industry, and history, and if it does not serve them it is a puerile and a trifling science." He condemned the analysis of the eighteenth century, which "dissolves and corrupts everything"; to vain ideology, to the question whether "ideas and sensations, memory and reminiscence are distinct faculties," he preferred "an Argentine philosophy in which are distilled the social and moral needs of our country; a clear, democratic, progressive, and popular philosophy, with ideas like those of Condorcet; human perfectibility, continual progress of the human species; a philosophy which inspires men with the love of country and the love of humanity."

The champions of liberalism defined the principles of the new social state; they were brilliant commentators, their subject being the ideas of French and Spanish philosophy. Their action in a society in which the old colonial prejudices were still triumphant was categorical and magistral. They created institutions and laws, and applied foreign doctrines to the troubles of the time. Sometimes they seemed inspired in the Biblical sense; they prophesied and condemned, as did Bilbao and Echeverria.

Lastarria, Bilbao, Montalvo, Vigil, and Sarmiento were the leading figures of this romantic period; with them intellectual activity was inseparable from politics. Lastarria and Bilbao opposed the authoritarianism of Chili; Montalvo and Vigil respectively, the clericalism of Ecuador and Peru; Sarmiento, the tyranny of Rosas. Their works were pamphlets, their theories were always practical: criticisms of contemporary reality, or constructive sketches of the State of the future.

Lastarria and Bilbao were the professors of liberalism in Chili. The liberalism of the first was tempered by the influence of Comte, and the study of philosophy and history; that of the second, indisciplined and prophetic, was eventually the bitter protest of a misunderstood evangelist.

Lastarria was the great Chilian reformer, as Bello was the prudent master who disciplined youth and defended tradition and the classic ideology. He was, like Bilbao, a pupil of Bello's, but to the conservative doctrines of the latter he opposed a generous liberalism. He was professor of legislation at the National Institute of Santiago from 1841, and from his professorial chair he criticised Chilian laws and prejudices. At first he followed Bentham in his lectures on constitutional law, and then the French liberals. He was influenced by Herder, by Edgar Quinet, a jurist and a disciple of Krause, and by Ahrens. Finally he accepted certain ideas of Comte's—for instance, the theory of the Three Estates—and endeavoured to reconcile his teaching with that of John Stuart Mill, Toqueville, and Laboulaye.

He believed, as did the romantics, in indefinite progress, liberty, universal harmony, and the power of man as against the inevitability of physical laws; in 1846 his political studies won the eulogy of Edgar Quinet. From a liberal standpoint he studied the evolution of Chili from the Conquest to the Republic.

In the defence of his political faith the professor intervened in the struggles of his country; academic dissertations did not satisfy him; he felt the need of action, of parliamentary agitation. As deputy and publicist he opposed the influence of Portales, the representative of the Chilian oligarchy, and the Constitution of 1833, that admirable piece of conservative legislation. "The State," said Lastarria, "has for its object the respect of the rights of the individual: there is the limit of its action." Portales, on the other hand, considered a strong central authority, a stern tutelage, to be a necessity in the South American republics, subject as they were to crises of anarchy. Liberty seemed to him a premature gift where the crowd was concerned. Lastarria opposed the positive work of the dictator by a vague idealism: liberty of conscience, of work, of association; an executive powerless to limit these liberties; municipal government, federation—such were the fundamental items of his propaganda. In the generality of American constitutions he disapproved of the vague definition of individual rights, the attributions of the public powers, the irresponsibility of these latter, and the amalgamation of colonial political forms with the administrative centralisation of the French régime.

Two Presidents, Bulnes and Montt, from 1841 to 1861, continued the despotic system founded by Portales; against them the liberal professor commenced his magnificent campaign. He was exiled in 1850. He travelled, and continued to publish his political writings. He had studied Comte, Mill, and Toqueville, and he now completed his education in certain directions. His next book, Lessons in Positivist Politics (1874), applied the principles of the Positivist school to the evolution of South America and to Chilian history in particular. He studied the organisation of the powers of the State, of society, and government, and abandoned his former radicalism. He recognised the fact that where Catholicism is the religion of the majority (as in Chili) the State may protect the national Church while exercising the moderate supervision that is known as "patronage."

Lastarria influenced the destinies of Chili. At his death the liberals came into power, and politicians like Santa-Maria and Balmaceda, who supported liberal legislation, may be regarded as disciples of the author of Positivist Politics.

Lastarria was a politician, Bilbao an apocalyptic dreamer. He founded the "Society of Equality," which was a democratic club. A generous and radical nature, he criticised, in a celebrated article on Chilian Sociability (1844), "the tradition, the ancient authority, the faith, the servile customs, the national apathy, the dogma of blind obedience, the respect for the established order, the hatred of innovation, and the persecution of the innovator," which he deplored in his native country. He gave a pitiless analysis of Chilian prejudices, and studied the national problems—commerce, education, marriage, taxation, the functions of Church and State—and answered them in a democratic sense. He was accused of immorality, blasphemy, and sedition. He also attacked the Constitution of 1833, and the minister Montt could not forgive him for this liberal campaign. Ten years later Bilbao was exiled for his leanings toward anarchy, and in Paris he became acquainted with Quinet and Lamennais, the evangelists of his democratic faith. In 1880, on his return to Chili, he resumed his inflammatory courses.