After having criticised and scourged the religions of chimera, of ignorance, and hypocrisy, in "Lo Spaccio della Bestia Trionfante" and in "L'Asino Cillenico," the author, in "Gli Eroici Furori," lays down the basis for the religion of thought and of science. In place of the so-called Christian perfections (resignation, devotion, and ignorance), Bruno would put intelligence and the progress of the intellect in the world of physics, metaphysics, and morals; the true aim being illumination, the true morality the practice of justice, the true redemption the liberation of the soul from error, its elevation and union with God upon the wings of thought. This idea is developed in the work in question, which is dedicated to Sir Philip Sidney. After treating of the infinite universe, and contemplating the innumerable worlds in other works, he comes, in "Gli Eroici Furori," to the consideration of virtue in the individual, and demonstrates the potency of the human faculties. After the Cosmos, the Microcosm; after the infinitely great, the infinitely small. The body is in the soul, the soul is in the mind, the mind is in God. The life of the soul is the true life of the man. Of all his various faculties, that which rules all, that which exalts our nature, is Thought. By means of it we rise to the contemplation of the universe, and becoming in our turn creators, we raise the edifice of science; through the intellect the affections become purified, the will becomes strengthened. True liberty is acquired, and will and action becoming one through thought, we become heroes.
This education of the soul, or rather this elevation and glory of thought, which draws with it the will and the affections, not by means of blind faith or supernatural grace, not through an irrational and mystical impulse, but by the strength of a reformed intellect and by a palpable and well-considered enthusiasm, which science and the contemplation of Nature alone can give, this is the keynote of the poem. It is composed of two parts, each of which is divided into five dialogues: the first part, which may be called psychological, shows, by means of various figures and symbols drawn from Nature, how the divine light is always present to us, is inherent in man; it presents itself to the senses and to the comprehension: man constantly rejects and ignores it; sometimes the soul strives to rise up to it, and the poet describes the struggle with the opposing affections which are involved in this effort, and shows how at last the man of intelligence overcomes these contending powers and fatal impulses which conflict within us, and by virtue of harmony and the fusion of the opposites the intellect becomes one with the affections, and man realizes the good and rises to the knowledge of the true. All conflicting desires being at last united, they become fixed upon one object, one great intent--the love of the Divine, which is the highest truth and the highest good. In "Gli Eroici Furori" we see Bruno as a man, as a philosopher, and as a believer: here he reveals himself as the hero of thought. Even as Christ was the hero of faith, and sacrificed himself for it, so Bruno declares himself ready to sacrifice himself for science. It is also a literary, a philosophical, and a religious work; form, however, is sacrificed to the idea--so absorbed is the author in the idea that he often ignores form altogether. An exile wandering from place to place, he wrote hurriedly and seldom or ever had he the opportunity of revising what he had written down. His mind in the impulsiveness of its improvisation was like the volcano of his native soil, which, rent by subterranean flames, sends forth from its vortices of fire, at the same time smoke, ashes, turbid floods, stones, and lava. He contemplates the soul, and seeks to understand its language; he is a physiologist and a naturalist, merged in the mystic and the enlightened devotee.