Huygens writes 'Cosmotheoros', a philosophical treatise arguing for the possibility and even probability of extraterrestrial life. He posits that other planets, like Earth, are likely inhabited by intelligent beings.

'Cosmotheoros' is published posthumously, sparking considerable interest and debate. Its publication contributes to the growing scientific and philosophical discussion about the possibility of life beyond Earth.

Huygens' 'Cosmotheoros' influences later thinkers, including astronomers, philosophers, and writers of science fiction. Its arguments and speculations contribute to the development of cosmology and the exploration of extraterrestrial life in literature and science.