Giordano Bruno

Giordano Bruno (1548–1600) was an Italian philosopher who argued that the universe is infinite and contains innumerable worlds. His cosmology extended beyond the Sun-centered model to a boundless cosmos without a unique center.

Nicolaus Copernicus: A Polish astronomer whose heliocentric model placed the Sun near the center of the planetary system. Copernicus displaced Earth from the cosmic center, a starting point Bruno carried much further.
Infinite universe: A cosmological model in which space has no finite boundary. Bruno argued that the universe has no outer limit or privileged center.
Dominican Order: A Catholic religious order founded to preach, teach, and defend Christian doctrine. Bruno joined the order as a young man before leaving it amid doctrinal conflict.
Lucretius: A Roman poet and philosopher whose poem On the Nature of Things presents Epicurean atomism. Lucretius transmitted ancient arguments for innumerable worlds that Bruno could draw upon.
Roman Inquisition: A Catholic tribunal established to investigate and prosecute suspected heresy. The Roman Inquisition tried Bruno over a broad set of theological and philosophical charges.
Aristotelian cosmology: An ancient model of a finite, Earth-centered cosmos composed of nested celestial spheres. Bruno rejected its finite, bounded universe and separation between earthly and heavenly matter.
Plurality of worlds: The claim that celestial bodies beyond Earth may host other worlds. Bruno held that innumerable stars are suns accompanied by worlds.
Pope Clement VIII: The pope of the Catholic Church from 1592 to 1605. Bruno’s Roman trial concluded under Clement VIII, who approved his condemnation.
Epicureanism: An ancient Greek philosophical school that explained nature through atoms and sought freedom from fear. Its atomist cosmology offered a historical precedent for worlds beyond the known Earth.
Campo de' Fiori: A public square in Rome where Giordano Bruno was executed in 1600. Bruno was burned there after refusing to recant the propositions condemned by the tribunal.

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